sqlglot.generator

   1from __future__ import annotations
   2
   3import logging
   4import re
   5import typing as t
   6from collections import defaultdict
   7from functools import reduce
   8
   9from sqlglot import exp
  10from sqlglot.errors import ErrorLevel, UnsupportedError, concat_messages
  11from sqlglot.helper import apply_index_offset, csv, seq_get
  12from sqlglot.time import format_time
  13from sqlglot.tokens import TokenType
  14
  15if t.TYPE_CHECKING:
  16    from sqlglot._typing import E
  17    from sqlglot.dialects.dialect import DialectType
  18
  19logger = logging.getLogger("sqlglot")
  20
  21ESCAPED_UNICODE_RE = re.compile(r"\\(\d+)")
  22
  23
  24class Generator:
  25    """
  26    Generator converts a given syntax tree to the corresponding SQL string.
  27
  28    Args:
  29        pretty: Whether or not to format the produced SQL string.
  30            Default: False.
  31        identify: Determines when an identifier should be quoted. Possible values are:
  32            False (default): Never quote, except in cases where it's mandatory by the dialect.
  33            True or 'always': Always quote.
  34            'safe': Only quote identifiers that are case insensitive.
  35        normalize: Whether or not to normalize identifiers to lowercase.
  36            Default: False.
  37        pad: Determines the pad size in a formatted string.
  38            Default: 2.
  39        indent: Determines the indentation size in a formatted string.
  40            Default: 2.
  41        normalize_functions: Whether or not to normalize all function names. Possible values are:
  42            "upper" or True (default): Convert names to uppercase.
  43            "lower": Convert names to lowercase.
  44            False: Disables function name normalization.
  45        unsupported_level: Determines the generator's behavior when it encounters unsupported expressions.
  46            Default ErrorLevel.WARN.
  47        max_unsupported: Maximum number of unsupported messages to include in a raised UnsupportedError.
  48            This is only relevant if unsupported_level is ErrorLevel.RAISE.
  49            Default: 3
  50        leading_comma: Determines whether or not the comma is leading or trailing in select expressions.
  51            This is only relevant when generating in pretty mode.
  52            Default: False
  53        max_text_width: The max number of characters in a segment before creating new lines in pretty mode.
  54            The default is on the smaller end because the length only represents a segment and not the true
  55            line length.
  56            Default: 80
  57        comments: Whether or not to preserve comments in the output SQL code.
  58            Default: True
  59    """
  60
  61    TRANSFORMS = {
  62        exp.DateAdd: lambda self, e: self.func(
  63            "DATE_ADD", e.this, e.expression, exp.Literal.string(e.text("unit"))
  64        ),
  65        exp.CaseSpecificColumnConstraint: lambda self, e: f"{'NOT ' if e.args.get('not_') else ''}CASESPECIFIC",
  66        exp.CharacterSetColumnConstraint: lambda self, e: f"CHARACTER SET {self.sql(e, 'this')}",
  67        exp.CharacterSetProperty: lambda self, e: f"{'DEFAULT ' if e.args.get('default') else ''}CHARACTER SET={self.sql(e, 'this')}",
  68        exp.CheckColumnConstraint: lambda self, e: f"CHECK ({self.sql(e, 'this')})",
  69        exp.ClusteredColumnConstraint: lambda self, e: f"CLUSTERED ({self.expressions(e, 'this', indent=False)})",
  70        exp.CollateColumnConstraint: lambda self, e: f"COLLATE {self.sql(e, 'this')}",
  71        exp.AutoRefreshProperty: lambda self, e: f"AUTO REFRESH {self.sql(e, 'this')}",
  72        exp.CopyGrantsProperty: lambda self, e: "COPY GRANTS",
  73        exp.CommentColumnConstraint: lambda self, e: f"COMMENT {self.sql(e, 'this')}",
  74        exp.DateFormatColumnConstraint: lambda self, e: f"FORMAT {self.sql(e, 'this')}",
  75        exp.DefaultColumnConstraint: lambda self, e: f"DEFAULT {self.sql(e, 'this')}",
  76        exp.EncodeColumnConstraint: lambda self, e: f"ENCODE {self.sql(e, 'this')}",
  77        exp.ExecuteAsProperty: lambda self, e: self.naked_property(e),
  78        exp.ExternalProperty: lambda self, e: "EXTERNAL",
  79        exp.HeapProperty: lambda self, e: "HEAP",
  80        exp.InheritsProperty: lambda self, e: f"INHERITS ({self.expressions(e, flat=True)})",
  81        exp.InlineLengthColumnConstraint: lambda self, e: f"INLINE LENGTH {self.sql(e, 'this')}",
  82        exp.InputModelProperty: lambda self, e: f"INPUT{self.sql(e, 'this')}",
  83        exp.IntervalSpan: lambda self, e: f"{self.sql(e, 'this')} TO {self.sql(e, 'expression')}",
  84        exp.LanguageProperty: lambda self, e: self.naked_property(e),
  85        exp.LocationProperty: lambda self, e: self.naked_property(e),
  86        exp.LogProperty: lambda self, e: f"{'NO ' if e.args.get('no') else ''}LOG",
  87        exp.MaterializedProperty: lambda self, e: "MATERIALIZED",
  88        exp.NoPrimaryIndexProperty: lambda self, e: "NO PRIMARY INDEX",
  89        exp.NonClusteredColumnConstraint: lambda self, e: f"NONCLUSTERED ({self.expressions(e, 'this', indent=False)})",
  90        exp.NotForReplicationColumnConstraint: lambda self, e: "NOT FOR REPLICATION",
  91        exp.OnCommitProperty: lambda self, e: f"ON COMMIT {'DELETE' if e.args.get('delete') else 'PRESERVE'} ROWS",
  92        exp.OnProperty: lambda self, e: f"ON {self.sql(e, 'this')}",
  93        exp.OnUpdateColumnConstraint: lambda self, e: f"ON UPDATE {self.sql(e, 'this')}",
  94        exp.OutputModelProperty: lambda self, e: f"OUTPUT{self.sql(e, 'this')}",
  95        exp.PathColumnConstraint: lambda self, e: f"PATH {self.sql(e, 'this')}",
  96        exp.RemoteWithConnectionModelProperty: lambda self, e: f"REMOTE WITH CONNECTION {self.sql(e, 'this')}",
  97        exp.ReturnsProperty: lambda self, e: self.naked_property(e),
  98        exp.SampleProperty: lambda self, e: f"SAMPLE BY {self.sql(e, 'this')}",
  99        exp.SetProperty: lambda self, e: f"{'MULTI' if e.args.get('multi') else ''}SET",
 100        exp.SetConfigProperty: lambda self, e: self.sql(e, "this"),
 101        exp.SettingsProperty: lambda self, e: f"SETTINGS{self.seg('')}{(self.expressions(e))}",
 102        exp.SqlReadWriteProperty: lambda self, e: e.name,
 103        exp.SqlSecurityProperty: lambda self, e: f"SQL SECURITY {'DEFINER' if e.args.get('definer') else 'INVOKER'}",
 104        exp.StabilityProperty: lambda self, e: e.name,
 105        exp.TemporaryProperty: lambda self, e: f"TEMPORARY",
 106        exp.ToTableProperty: lambda self, e: f"TO {self.sql(e.this)}",
 107        exp.TransientProperty: lambda self, e: "TRANSIENT",
 108        exp.TransformModelProperty: lambda self, e: self.func("TRANSFORM", *e.expressions),
 109        exp.TitleColumnConstraint: lambda self, e: f"TITLE {self.sql(e, 'this')}",
 110        exp.UppercaseColumnConstraint: lambda self, e: f"UPPERCASE",
 111        exp.VarMap: lambda self, e: self.func("MAP", e.args["keys"], e.args["values"]),
 112        exp.VolatileProperty: lambda self, e: "VOLATILE",
 113        exp.WithJournalTableProperty: lambda self, e: f"WITH JOURNAL TABLE={self.sql(e, 'this')}",
 114    }
 115
 116    # Whether or not null ordering is supported in order by
 117    # True: Full Support, None: No support, False: No support in window specifications
 118    NULL_ORDERING_SUPPORTED: t.Optional[bool] = True
 119
 120    # Whether or not locking reads (i.e. SELECT ... FOR UPDATE/SHARE) are supported
 121    LOCKING_READS_SUPPORTED = False
 122
 123    # Always do union distinct or union all
 124    EXPLICIT_UNION = False
 125
 126    # Wrap derived values in parens, usually standard but spark doesn't support it
 127    WRAP_DERIVED_VALUES = True
 128
 129    # Whether or not create function uses an AS before the RETURN
 130    CREATE_FUNCTION_RETURN_AS = True
 131
 132    # Whether or not MERGE ... WHEN MATCHED BY SOURCE is allowed
 133    MATCHED_BY_SOURCE = True
 134
 135    # Whether or not the INTERVAL expression works only with values like '1 day'
 136    SINGLE_STRING_INTERVAL = False
 137
 138    # Whether or not the plural form of date parts like day (i.e. "days") is supported in INTERVALs
 139    INTERVAL_ALLOWS_PLURAL_FORM = True
 140
 141    # Whether or not limit and fetch are supported (possible values: "ALL", "LIMIT", "FETCH")
 142    LIMIT_FETCH = "ALL"
 143
 144    # Whether or not limit and fetch allows expresions or just limits
 145    LIMIT_ONLY_LITERALS = False
 146
 147    # Whether or not a table is allowed to be renamed with a db
 148    RENAME_TABLE_WITH_DB = True
 149
 150    # The separator for grouping sets and rollups
 151    GROUPINGS_SEP = ","
 152
 153    # The string used for creating an index on a table
 154    INDEX_ON = "ON"
 155
 156    # Whether or not join hints should be generated
 157    JOIN_HINTS = True
 158
 159    # Whether or not table hints should be generated
 160    TABLE_HINTS = True
 161
 162    # Whether or not query hints should be generated
 163    QUERY_HINTS = True
 164
 165    # What kind of separator to use for query hints
 166    QUERY_HINT_SEP = ", "
 167
 168    # Whether or not comparing against booleans (e.g. x IS TRUE) is supported
 169    IS_BOOL_ALLOWED = True
 170
 171    # Whether or not to include the "SET" keyword in the "INSERT ... ON DUPLICATE KEY UPDATE" statement
 172    DUPLICATE_KEY_UPDATE_WITH_SET = True
 173
 174    # Whether or not to generate the limit as TOP <value> instead of LIMIT <value>
 175    LIMIT_IS_TOP = False
 176
 177    # Whether or not to generate INSERT INTO ... RETURNING or INSERT INTO RETURNING ...
 178    RETURNING_END = True
 179
 180    # Whether or not to generate the (+) suffix for columns used in old-style join conditions
 181    COLUMN_JOIN_MARKS_SUPPORTED = False
 182
 183    # Whether or not to generate an unquoted value for EXTRACT's date part argument
 184    EXTRACT_ALLOWS_QUOTES = True
 185
 186    # Whether or not TIMETZ / TIMESTAMPTZ will be generated using the "WITH TIME ZONE" syntax
 187    TZ_TO_WITH_TIME_ZONE = False
 188
 189    # Whether or not the NVL2 function is supported
 190    NVL2_SUPPORTED = True
 191
 192    # https://cloud.google.com/bigquery/docs/reference/standard-sql/query-syntax
 193    SELECT_KINDS: t.Tuple[str, ...] = ("STRUCT", "VALUE")
 194
 195    # Whether or not VALUES statements can be used as derived tables.
 196    # MySQL 5 and Redshift do not allow this, so when False, it will convert
 197    # SELECT * VALUES into SELECT UNION
 198    VALUES_AS_TABLE = True
 199
 200    # Whether or not the word COLUMN is included when adding a column with ALTER TABLE
 201    ALTER_TABLE_INCLUDE_COLUMN_KEYWORD = True
 202
 203    # UNNEST WITH ORDINALITY (presto) instead of UNNEST WITH OFFSET (bigquery)
 204    UNNEST_WITH_ORDINALITY = True
 205
 206    # Whether or not FILTER (WHERE cond) can be used for conditional aggregation
 207    AGGREGATE_FILTER_SUPPORTED = True
 208
 209    # Whether or not JOIN sides (LEFT, RIGHT) are supported in conjunction with SEMI/ANTI join kinds
 210    SEMI_ANTI_JOIN_WITH_SIDE = True
 211
 212    # Whether or not to include the type of a computed column in the CREATE DDL
 213    COMPUTED_COLUMN_WITH_TYPE = True
 214
 215    # Whether or not CREATE TABLE .. COPY .. is supported. False means we'll generate CLONE instead of COPY
 216    SUPPORTS_TABLE_COPY = True
 217
 218    # Whether or not parentheses are required around the table sample's expression
 219    TABLESAMPLE_REQUIRES_PARENS = True
 220
 221    # Whether or not a table sample clause's size needs to be followed by the ROWS keyword
 222    TABLESAMPLE_SIZE_IS_ROWS = True
 223
 224    # The keyword(s) to use when generating a sample clause
 225    TABLESAMPLE_KEYWORDS = "TABLESAMPLE"
 226
 227    # Whether or not the TABLESAMPLE clause supports a method name, like BERNOULLI
 228    TABLESAMPLE_WITH_METHOD = True
 229
 230    # The keyword to use when specifying the seed of a sample clause
 231    TABLESAMPLE_SEED_KEYWORD = "SEED"
 232
 233    # Whether or not COLLATE is a function instead of a binary operator
 234    COLLATE_IS_FUNC = False
 235
 236    # Whether or not data types support additional specifiers like e.g. CHAR or BYTE (oracle)
 237    DATA_TYPE_SPECIFIERS_ALLOWED = False
 238
 239    # Whether or not conditions require booleans WHERE x = 0 vs WHERE x
 240    ENSURE_BOOLS = False
 241
 242    # Whether or not the "RECURSIVE" keyword is required when defining recursive CTEs
 243    CTE_RECURSIVE_KEYWORD_REQUIRED = True
 244
 245    # Whether or not CONCAT requires >1 arguments
 246    SUPPORTS_SINGLE_ARG_CONCAT = True
 247
 248    # Whether or not LAST_DAY function supports a date part argument
 249    LAST_DAY_SUPPORTS_DATE_PART = True
 250
 251    # Whether or not named columns are allowed in table aliases
 252    SUPPORTS_TABLE_ALIAS_COLUMNS = True
 253
 254    # Whether or not UNPIVOT aliases are Identifiers (False means they're Literals)
 255    UNPIVOT_ALIASES_ARE_IDENTIFIERS = True
 256
 257    # What delimiter to use for separating JSON key/value pairs
 258    JSON_KEY_VALUE_PAIR_SEP = ":"
 259
 260    # INSERT OVERWRITE TABLE x override
 261    INSERT_OVERWRITE = " OVERWRITE TABLE"
 262
 263    # Whether or not the SELECT .. INTO syntax is used instead of CTAS
 264    SUPPORTS_SELECT_INTO = False
 265
 266    # Whether or not UNLOGGED tables can be created
 267    SUPPORTS_UNLOGGED_TABLES = False
 268
 269    TYPE_MAPPING = {
 270        exp.DataType.Type.NCHAR: "CHAR",
 271        exp.DataType.Type.NVARCHAR: "VARCHAR",
 272        exp.DataType.Type.MEDIUMTEXT: "TEXT",
 273        exp.DataType.Type.LONGTEXT: "TEXT",
 274        exp.DataType.Type.TINYTEXT: "TEXT",
 275        exp.DataType.Type.MEDIUMBLOB: "BLOB",
 276        exp.DataType.Type.LONGBLOB: "BLOB",
 277        exp.DataType.Type.TINYBLOB: "BLOB",
 278        exp.DataType.Type.INET: "INET",
 279    }
 280
 281    STAR_MAPPING = {
 282        "except": "EXCEPT",
 283        "replace": "REPLACE",
 284    }
 285
 286    TIME_PART_SINGULARS = {
 287        "MICROSECONDS": "MICROSECOND",
 288        "SECONDS": "SECOND",
 289        "MINUTES": "MINUTE",
 290        "HOURS": "HOUR",
 291        "DAYS": "DAY",
 292        "WEEKS": "WEEK",
 293        "MONTHS": "MONTH",
 294        "QUARTERS": "QUARTER",
 295        "YEARS": "YEAR",
 296    }
 297
 298    TOKEN_MAPPING: t.Dict[TokenType, str] = {}
 299
 300    STRUCT_DELIMITER = ("<", ">")
 301
 302    PARAMETER_TOKEN = "@"
 303
 304    PROPERTIES_LOCATION = {
 305        exp.AlgorithmProperty: exp.Properties.Location.POST_CREATE,
 306        exp.AutoIncrementProperty: exp.Properties.Location.POST_SCHEMA,
 307        exp.AutoRefreshProperty: exp.Properties.Location.POST_SCHEMA,
 308        exp.BlockCompressionProperty: exp.Properties.Location.POST_NAME,
 309        exp.CharacterSetProperty: exp.Properties.Location.POST_SCHEMA,
 310        exp.ChecksumProperty: exp.Properties.Location.POST_NAME,
 311        exp.CollateProperty: exp.Properties.Location.POST_SCHEMA,
 312        exp.CopyGrantsProperty: exp.Properties.Location.POST_SCHEMA,
 313        exp.Cluster: exp.Properties.Location.POST_SCHEMA,
 314        exp.ClusteredByProperty: exp.Properties.Location.POST_SCHEMA,
 315        exp.DataBlocksizeProperty: exp.Properties.Location.POST_NAME,
 316        exp.DefinerProperty: exp.Properties.Location.POST_CREATE,
 317        exp.DictRange: exp.Properties.Location.POST_SCHEMA,
 318        exp.DictProperty: exp.Properties.Location.POST_SCHEMA,
 319        exp.DistKeyProperty: exp.Properties.Location.POST_SCHEMA,
 320        exp.DistStyleProperty: exp.Properties.Location.POST_SCHEMA,
 321        exp.EngineProperty: exp.Properties.Location.POST_SCHEMA,
 322        exp.ExecuteAsProperty: exp.Properties.Location.POST_SCHEMA,
 323        exp.ExternalProperty: exp.Properties.Location.POST_CREATE,
 324        exp.FallbackProperty: exp.Properties.Location.POST_NAME,
 325        exp.FileFormatProperty: exp.Properties.Location.POST_WITH,
 326        exp.FreespaceProperty: exp.Properties.Location.POST_NAME,
 327        exp.HeapProperty: exp.Properties.Location.POST_WITH,
 328        exp.InheritsProperty: exp.Properties.Location.POST_SCHEMA,
 329        exp.InputModelProperty: exp.Properties.Location.POST_SCHEMA,
 330        exp.IsolatedLoadingProperty: exp.Properties.Location.POST_NAME,
 331        exp.JournalProperty: exp.Properties.Location.POST_NAME,
 332        exp.LanguageProperty: exp.Properties.Location.POST_SCHEMA,
 333        exp.LikeProperty: exp.Properties.Location.POST_SCHEMA,
 334        exp.LocationProperty: exp.Properties.Location.POST_SCHEMA,
 335        exp.LockingProperty: exp.Properties.Location.POST_ALIAS,
 336        exp.LogProperty: exp.Properties.Location.POST_NAME,
 337        exp.MaterializedProperty: exp.Properties.Location.POST_CREATE,
 338        exp.MergeBlockRatioProperty: exp.Properties.Location.POST_NAME,
 339        exp.NoPrimaryIndexProperty: exp.Properties.Location.POST_EXPRESSION,
 340        exp.OnProperty: exp.Properties.Location.POST_SCHEMA,
 341        exp.OnCommitProperty: exp.Properties.Location.POST_EXPRESSION,
 342        exp.Order: exp.Properties.Location.POST_SCHEMA,
 343        exp.OutputModelProperty: exp.Properties.Location.POST_SCHEMA,
 344        exp.PartitionedByProperty: exp.Properties.Location.POST_WITH,
 345        exp.PartitionedOfProperty: exp.Properties.Location.POST_SCHEMA,
 346        exp.PrimaryKey: exp.Properties.Location.POST_SCHEMA,
 347        exp.Property: exp.Properties.Location.POST_WITH,
 348        exp.RemoteWithConnectionModelProperty: exp.Properties.Location.POST_SCHEMA,
 349        exp.ReturnsProperty: exp.Properties.Location.POST_SCHEMA,
 350        exp.RowFormatProperty: exp.Properties.Location.POST_SCHEMA,
 351        exp.RowFormatDelimitedProperty: exp.Properties.Location.POST_SCHEMA,
 352        exp.RowFormatSerdeProperty: exp.Properties.Location.POST_SCHEMA,
 353        exp.SampleProperty: exp.Properties.Location.POST_SCHEMA,
 354        exp.SchemaCommentProperty: exp.Properties.Location.POST_SCHEMA,
 355        exp.SerdeProperties: exp.Properties.Location.POST_SCHEMA,
 356        exp.Set: exp.Properties.Location.POST_SCHEMA,
 357        exp.SettingsProperty: exp.Properties.Location.POST_SCHEMA,
 358        exp.SetProperty: exp.Properties.Location.POST_CREATE,
 359        exp.SetConfigProperty: exp.Properties.Location.POST_SCHEMA,
 360        exp.SortKeyProperty: exp.Properties.Location.POST_SCHEMA,
 361        exp.SqlReadWriteProperty: exp.Properties.Location.POST_SCHEMA,
 362        exp.SqlSecurityProperty: exp.Properties.Location.POST_CREATE,
 363        exp.StabilityProperty: exp.Properties.Location.POST_SCHEMA,
 364        exp.TemporaryProperty: exp.Properties.Location.POST_CREATE,
 365        exp.ToTableProperty: exp.Properties.Location.POST_SCHEMA,
 366        exp.TransientProperty: exp.Properties.Location.POST_CREATE,
 367        exp.TransformModelProperty: exp.Properties.Location.POST_SCHEMA,
 368        exp.MergeTreeTTL: exp.Properties.Location.POST_SCHEMA,
 369        exp.VolatileProperty: exp.Properties.Location.POST_CREATE,
 370        exp.WithDataProperty: exp.Properties.Location.POST_EXPRESSION,
 371        exp.WithJournalTableProperty: exp.Properties.Location.POST_NAME,
 372        exp.WithSystemVersioningProperty: exp.Properties.Location.POST_SCHEMA,
 373    }
 374
 375    # Keywords that can't be used as unquoted identifier names
 376    RESERVED_KEYWORDS: t.Set[str] = set()
 377
 378    # Expressions whose comments are separated from them for better formatting
 379    WITH_SEPARATED_COMMENTS: t.Tuple[t.Type[exp.Expression], ...] = (
 380        exp.Create,
 381        exp.Delete,
 382        exp.Drop,
 383        exp.From,
 384        exp.Insert,
 385        exp.Join,
 386        exp.Select,
 387        exp.Update,
 388        exp.Where,
 389        exp.With,
 390    )
 391
 392    # Expressions that should not have their comments generated in maybe_comment
 393    EXCLUDE_COMMENTS: t.Tuple[t.Type[exp.Expression], ...] = (
 394        exp.Binary,
 395        exp.Union,
 396    )
 397
 398    # Expressions that can remain unwrapped when appearing in the context of an INTERVAL
 399    UNWRAPPED_INTERVAL_VALUES: t.Tuple[t.Type[exp.Expression], ...] = (
 400        exp.Column,
 401        exp.Literal,
 402        exp.Neg,
 403        exp.Paren,
 404    )
 405
 406    # Expressions that need to have all CTEs under them bubbled up to them
 407    EXPRESSIONS_WITHOUT_NESTED_CTES: t.Set[t.Type[exp.Expression]] = set()
 408
 409    KEY_VALUE_DEFINITIONS = (exp.Bracket, exp.EQ, exp.PropertyEQ, exp.Slice)
 410
 411    SENTINEL_LINE_BREAK = "__SQLGLOT__LB__"
 412
 413    __slots__ = (
 414        "pretty",
 415        "identify",
 416        "normalize",
 417        "pad",
 418        "_indent",
 419        "normalize_functions",
 420        "unsupported_level",
 421        "max_unsupported",
 422        "leading_comma",
 423        "max_text_width",
 424        "comments",
 425        "dialect",
 426        "unsupported_messages",
 427        "_escaped_quote_end",
 428        "_escaped_identifier_end",
 429    )
 430
 431    def __init__(
 432        self,
 433        pretty: t.Optional[bool] = None,
 434        identify: str | bool = False,
 435        normalize: bool = False,
 436        pad: int = 2,
 437        indent: int = 2,
 438        normalize_functions: t.Optional[str | bool] = None,
 439        unsupported_level: ErrorLevel = ErrorLevel.WARN,
 440        max_unsupported: int = 3,
 441        leading_comma: bool = False,
 442        max_text_width: int = 80,
 443        comments: bool = True,
 444        dialect: DialectType = None,
 445    ):
 446        import sqlglot
 447        from sqlglot.dialects import Dialect
 448
 449        self.pretty = pretty if pretty is not None else sqlglot.pretty
 450        self.identify = identify
 451        self.normalize = normalize
 452        self.pad = pad
 453        self._indent = indent
 454        self.unsupported_level = unsupported_level
 455        self.max_unsupported = max_unsupported
 456        self.leading_comma = leading_comma
 457        self.max_text_width = max_text_width
 458        self.comments = comments
 459        self.dialect = Dialect.get_or_raise(dialect)
 460
 461        # This is both a Dialect property and a Generator argument, so we prioritize the latter
 462        self.normalize_functions = (
 463            self.dialect.NORMALIZE_FUNCTIONS if normalize_functions is None else normalize_functions
 464        )
 465
 466        self.unsupported_messages: t.List[str] = []
 467        self._escaped_quote_end: str = (
 468            self.dialect.tokenizer_class.STRING_ESCAPES[0] + self.dialect.QUOTE_END
 469        )
 470        self._escaped_identifier_end: str = (
 471            self.dialect.tokenizer_class.IDENTIFIER_ESCAPES[0] + self.dialect.IDENTIFIER_END
 472        )
 473
 474    def generate(self, expression: exp.Expression, copy: bool = True) -> str:
 475        """
 476        Generates the SQL string corresponding to the given syntax tree.
 477
 478        Args:
 479            expression: The syntax tree.
 480            copy: Whether or not to copy the expression. The generator performs mutations so
 481                it is safer to copy.
 482
 483        Returns:
 484            The SQL string corresponding to `expression`.
 485        """
 486        if copy:
 487            expression = expression.copy()
 488
 489        expression = self.preprocess(expression)
 490
 491        self.unsupported_messages = []
 492        sql = self.sql(expression).strip()
 493
 494        if self.pretty:
 495            sql = sql.replace(self.SENTINEL_LINE_BREAK, "\n")
 496
 497        if self.unsupported_level == ErrorLevel.IGNORE:
 498            return sql
 499
 500        if self.unsupported_level == ErrorLevel.WARN:
 501            for msg in self.unsupported_messages:
 502                logger.warning(msg)
 503        elif self.unsupported_level == ErrorLevel.RAISE and self.unsupported_messages:
 504            raise UnsupportedError(concat_messages(self.unsupported_messages, self.max_unsupported))
 505
 506        return sql
 507
 508    def preprocess(self, expression: exp.Expression) -> exp.Expression:
 509        """Apply generic preprocessing transformations to a given expression."""
 510        if (
 511            not expression.parent
 512            and type(expression) in self.EXPRESSIONS_WITHOUT_NESTED_CTES
 513            and any(node.parent is not expression for node in expression.find_all(exp.With))
 514        ):
 515            from sqlglot.transforms import move_ctes_to_top_level
 516
 517            expression = move_ctes_to_top_level(expression)
 518
 519        if self.ENSURE_BOOLS:
 520            from sqlglot.transforms import ensure_bools
 521
 522            expression = ensure_bools(expression)
 523
 524        return expression
 525
 526    def unsupported(self, message: str) -> None:
 527        if self.unsupported_level == ErrorLevel.IMMEDIATE:
 528            raise UnsupportedError(message)
 529        self.unsupported_messages.append(message)
 530
 531    def sep(self, sep: str = " ") -> str:
 532        return f"{sep.strip()}\n" if self.pretty else sep
 533
 534    def seg(self, sql: str, sep: str = " ") -> str:
 535        return f"{self.sep(sep)}{sql}"
 536
 537    def pad_comment(self, comment: str) -> str:
 538        comment = " " + comment if comment[0].strip() else comment
 539        comment = comment + " " if comment[-1].strip() else comment
 540        return comment
 541
 542    def maybe_comment(
 543        self,
 544        sql: str,
 545        expression: t.Optional[exp.Expression] = None,
 546        comments: t.Optional[t.List[str]] = None,
 547    ) -> str:
 548        comments = (
 549            ((expression and expression.comments) if comments is None else comments)  # type: ignore
 550            if self.comments
 551            else None
 552        )
 553
 554        if not comments or isinstance(expression, self.EXCLUDE_COMMENTS):
 555            return sql
 556
 557        comments_sql = " ".join(
 558            f"/*{self.pad_comment(comment)}*/" for comment in comments if comment
 559        )
 560
 561        if not comments_sql:
 562            return sql
 563
 564        if isinstance(expression, self.WITH_SEPARATED_COMMENTS):
 565            return (
 566                f"{self.sep()}{comments_sql}{sql}"
 567                if sql[0].isspace()
 568                else f"{comments_sql}{self.sep()}{sql}"
 569            )
 570
 571        return f"{sql} {comments_sql}"
 572
 573    def wrap(self, expression: exp.Expression | str) -> str:
 574        this_sql = self.indent(
 575            self.sql(expression)
 576            if isinstance(expression, (exp.Select, exp.Union))
 577            else self.sql(expression, "this"),
 578            level=1,
 579            pad=0,
 580        )
 581        return f"({self.sep('')}{this_sql}{self.seg(')', sep='')}"
 582
 583    def no_identify(self, func: t.Callable[..., str], *args, **kwargs) -> str:
 584        original = self.identify
 585        self.identify = False
 586        result = func(*args, **kwargs)
 587        self.identify = original
 588        return result
 589
 590    def normalize_func(self, name: str) -> str:
 591        if self.normalize_functions == "upper" or self.normalize_functions is True:
 592            return name.upper()
 593        if self.normalize_functions == "lower":
 594            return name.lower()
 595        return name
 596
 597    def indent(
 598        self,
 599        sql: str,
 600        level: int = 0,
 601        pad: t.Optional[int] = None,
 602        skip_first: bool = False,
 603        skip_last: bool = False,
 604    ) -> str:
 605        if not self.pretty:
 606            return sql
 607
 608        pad = self.pad if pad is None else pad
 609        lines = sql.split("\n")
 610
 611        return "\n".join(
 612            line
 613            if (skip_first and i == 0) or (skip_last and i == len(lines) - 1)
 614            else f"{' ' * (level * self._indent + pad)}{line}"
 615            for i, line in enumerate(lines)
 616        )
 617
 618    def sql(
 619        self,
 620        expression: t.Optional[str | exp.Expression],
 621        key: t.Optional[str] = None,
 622        comment: bool = True,
 623    ) -> str:
 624        if not expression:
 625            return ""
 626
 627        if isinstance(expression, str):
 628            return expression
 629
 630        if key:
 631            value = expression.args.get(key)
 632            if value:
 633                return self.sql(value)
 634            return ""
 635
 636        transform = self.TRANSFORMS.get(expression.__class__)
 637
 638        if callable(transform):
 639            sql = transform(self, expression)
 640        elif transform:
 641            sql = transform
 642        elif isinstance(expression, exp.Expression):
 643            exp_handler_name = f"{expression.key}_sql"
 644
 645            if hasattr(self, exp_handler_name):
 646                sql = getattr(self, exp_handler_name)(expression)
 647            elif isinstance(expression, exp.Func):
 648                sql = self.function_fallback_sql(expression)
 649            elif isinstance(expression, exp.Property):
 650                sql = self.property_sql(expression)
 651            else:
 652                raise ValueError(f"Unsupported expression type {expression.__class__.__name__}")
 653        else:
 654            raise ValueError(f"Expected an Expression. Received {type(expression)}: {expression}")
 655
 656        return self.maybe_comment(sql, expression) if self.comments and comment else sql
 657
 658    def uncache_sql(self, expression: exp.Uncache) -> str:
 659        table = self.sql(expression, "this")
 660        exists_sql = " IF EXISTS" if expression.args.get("exists") else ""
 661        return f"UNCACHE TABLE{exists_sql} {table}"
 662
 663    def cache_sql(self, expression: exp.Cache) -> str:
 664        lazy = " LAZY" if expression.args.get("lazy") else ""
 665        table = self.sql(expression, "this")
 666        options = expression.args.get("options")
 667        options = f" OPTIONS({self.sql(options[0])} = {self.sql(options[1])})" if options else ""
 668        sql = self.sql(expression, "expression")
 669        sql = f" AS{self.sep()}{sql}" if sql else ""
 670        sql = f"CACHE{lazy} TABLE {table}{options}{sql}"
 671        return self.prepend_ctes(expression, sql)
 672
 673    def characterset_sql(self, expression: exp.CharacterSet) -> str:
 674        if isinstance(expression.parent, exp.Cast):
 675            return f"CHAR CHARACTER SET {self.sql(expression, 'this')}"
 676        default = "DEFAULT " if expression.args.get("default") else ""
 677        return f"{default}CHARACTER SET={self.sql(expression, 'this')}"
 678
 679    def column_sql(self, expression: exp.Column) -> str:
 680        join_mark = " (+)" if expression.args.get("join_mark") else ""
 681
 682        if join_mark and not self.COLUMN_JOIN_MARKS_SUPPORTED:
 683            join_mark = ""
 684            self.unsupported("Outer join syntax using the (+) operator is not supported.")
 685
 686        column = ".".join(
 687            self.sql(part)
 688            for part in (
 689                expression.args.get("catalog"),
 690                expression.args.get("db"),
 691                expression.args.get("table"),
 692                expression.args.get("this"),
 693            )
 694            if part
 695        )
 696
 697        return f"{column}{join_mark}"
 698
 699    def columnposition_sql(self, expression: exp.ColumnPosition) -> str:
 700        this = self.sql(expression, "this")
 701        this = f" {this}" if this else ""
 702        position = self.sql(expression, "position")
 703        return f"{position}{this}"
 704
 705    def columndef_sql(self, expression: exp.ColumnDef, sep: str = " ") -> str:
 706        column = self.sql(expression, "this")
 707        kind = self.sql(expression, "kind")
 708        constraints = self.expressions(expression, key="constraints", sep=" ", flat=True)
 709        exists = "IF NOT EXISTS " if expression.args.get("exists") else ""
 710        kind = f"{sep}{kind}" if kind else ""
 711        constraints = f" {constraints}" if constraints else ""
 712        position = self.sql(expression, "position")
 713        position = f" {position}" if position else ""
 714
 715        if expression.find(exp.ComputedColumnConstraint) and not self.COMPUTED_COLUMN_WITH_TYPE:
 716            kind = ""
 717
 718        return f"{exists}{column}{kind}{constraints}{position}"
 719
 720    def columnconstraint_sql(self, expression: exp.ColumnConstraint) -> str:
 721        this = self.sql(expression, "this")
 722        kind_sql = self.sql(expression, "kind").strip()
 723        return f"CONSTRAINT {this} {kind_sql}" if this else kind_sql
 724
 725    def computedcolumnconstraint_sql(self, expression: exp.ComputedColumnConstraint) -> str:
 726        this = self.sql(expression, "this")
 727        if expression.args.get("not_null"):
 728            persisted = " PERSISTED NOT NULL"
 729        elif expression.args.get("persisted"):
 730            persisted = " PERSISTED"
 731        else:
 732            persisted = ""
 733        return f"AS {this}{persisted}"
 734
 735    def autoincrementcolumnconstraint_sql(self, _) -> str:
 736        return self.token_sql(TokenType.AUTO_INCREMENT)
 737
 738    def compresscolumnconstraint_sql(self, expression: exp.CompressColumnConstraint) -> str:
 739        if isinstance(expression.this, list):
 740            this = self.wrap(self.expressions(expression, key="this", flat=True))
 741        else:
 742            this = self.sql(expression, "this")
 743
 744        return f"COMPRESS {this}"
 745
 746    def generatedasidentitycolumnconstraint_sql(
 747        self, expression: exp.GeneratedAsIdentityColumnConstraint
 748    ) -> str:
 749        this = ""
 750        if expression.this is not None:
 751            on_null = " ON NULL" if expression.args.get("on_null") else ""
 752            this = " ALWAYS" if expression.this else f" BY DEFAULT{on_null}"
 753
 754        start = expression.args.get("start")
 755        start = f"START WITH {start}" if start else ""
 756        increment = expression.args.get("increment")
 757        increment = f" INCREMENT BY {increment}" if increment else ""
 758        minvalue = expression.args.get("minvalue")
 759        minvalue = f" MINVALUE {minvalue}" if minvalue else ""
 760        maxvalue = expression.args.get("maxvalue")
 761        maxvalue = f" MAXVALUE {maxvalue}" if maxvalue else ""
 762        cycle = expression.args.get("cycle")
 763        cycle_sql = ""
 764
 765        if cycle is not None:
 766            cycle_sql = f"{' NO' if not cycle else ''} CYCLE"
 767            cycle_sql = cycle_sql.strip() if not start and not increment else cycle_sql
 768
 769        sequence_opts = ""
 770        if start or increment or cycle_sql:
 771            sequence_opts = f"{start}{increment}{minvalue}{maxvalue}{cycle_sql}"
 772            sequence_opts = f" ({sequence_opts.strip()})"
 773
 774        expr = self.sql(expression, "expression")
 775        expr = f"({expr})" if expr else "IDENTITY"
 776
 777        return f"GENERATED{this} AS {expr}{sequence_opts}"
 778
 779    def generatedasrowcolumnconstraint_sql(
 780        self, expression: exp.GeneratedAsRowColumnConstraint
 781    ) -> str:
 782        start = "START" if expression.args.get("start") else "END"
 783        hidden = " HIDDEN" if expression.args.get("hidden") else ""
 784        return f"GENERATED ALWAYS AS ROW {start}{hidden}"
 785
 786    def periodforsystemtimeconstraint_sql(
 787        self, expression: exp.PeriodForSystemTimeConstraint
 788    ) -> str:
 789        return f"PERIOD FOR SYSTEM_TIME ({self.sql(expression, 'this')}, {self.sql(expression, 'expression')})"
 790
 791    def notnullcolumnconstraint_sql(self, expression: exp.NotNullColumnConstraint) -> str:
 792        return f"{'' if expression.args.get('allow_null') else 'NOT '}NULL"
 793
 794    def transformcolumnconstraint_sql(self, expression: exp.TransformColumnConstraint) -> str:
 795        return f"AS {self.sql(expression, 'this')}"
 796
 797    def primarykeycolumnconstraint_sql(self, expression: exp.PrimaryKeyColumnConstraint) -> str:
 798        desc = expression.args.get("desc")
 799        if desc is not None:
 800            return f"PRIMARY KEY{' DESC' if desc else ' ASC'}"
 801        return f"PRIMARY KEY"
 802
 803    def uniquecolumnconstraint_sql(self, expression: exp.UniqueColumnConstraint) -> str:
 804        this = self.sql(expression, "this")
 805        this = f" {this}" if this else ""
 806        index_type = expression.args.get("index_type")
 807        index_type = f" USING {index_type}" if index_type else ""
 808        return f"UNIQUE{this}{index_type}"
 809
 810    def createable_sql(self, expression: exp.Create, locations: t.DefaultDict) -> str:
 811        return self.sql(expression, "this")
 812
 813    def create_sql(self, expression: exp.Create) -> str:
 814        kind = self.sql(expression, "kind")
 815        properties = expression.args.get("properties")
 816        properties_locs = self.locate_properties(properties) if properties else defaultdict()
 817
 818        this = self.createable_sql(expression, properties_locs)
 819
 820        properties_sql = ""
 821        if properties_locs.get(exp.Properties.Location.POST_SCHEMA) or properties_locs.get(
 822            exp.Properties.Location.POST_WITH
 823        ):
 824            properties_sql = self.sql(
 825                exp.Properties(
 826                    expressions=[
 827                        *properties_locs[exp.Properties.Location.POST_SCHEMA],
 828                        *properties_locs[exp.Properties.Location.POST_WITH],
 829                    ]
 830                )
 831            )
 832
 833        begin = " BEGIN" if expression.args.get("begin") else ""
 834        end = " END" if expression.args.get("end") else ""
 835
 836        expression_sql = self.sql(expression, "expression")
 837        if expression_sql:
 838            expression_sql = f"{begin}{self.sep()}{expression_sql}{end}"
 839
 840            if self.CREATE_FUNCTION_RETURN_AS or not isinstance(expression.expression, exp.Return):
 841                if properties_locs.get(exp.Properties.Location.POST_ALIAS):
 842                    postalias_props_sql = self.properties(
 843                        exp.Properties(
 844                            expressions=properties_locs[exp.Properties.Location.POST_ALIAS]
 845                        ),
 846                        wrapped=False,
 847                    )
 848                    expression_sql = f" AS {postalias_props_sql}{expression_sql}"
 849                else:
 850                    expression_sql = f" AS{expression_sql}"
 851
 852        postindex_props_sql = ""
 853        if properties_locs.get(exp.Properties.Location.POST_INDEX):
 854            postindex_props_sql = self.properties(
 855                exp.Properties(expressions=properties_locs[exp.Properties.Location.POST_INDEX]),
 856                wrapped=False,
 857                prefix=" ",
 858            )
 859
 860        indexes = self.expressions(expression, key="indexes", indent=False, sep=" ")
 861        indexes = f" {indexes}" if indexes else ""
 862        index_sql = indexes + postindex_props_sql
 863
 864        replace = " OR REPLACE" if expression.args.get("replace") else ""
 865        unique = " UNIQUE" if expression.args.get("unique") else ""
 866
 867        postcreate_props_sql = ""
 868        if properties_locs.get(exp.Properties.Location.POST_CREATE):
 869            postcreate_props_sql = self.properties(
 870                exp.Properties(expressions=properties_locs[exp.Properties.Location.POST_CREATE]),
 871                sep=" ",
 872                prefix=" ",
 873                wrapped=False,
 874            )
 875
 876        modifiers = "".join((replace, unique, postcreate_props_sql))
 877
 878        postexpression_props_sql = ""
 879        if properties_locs.get(exp.Properties.Location.POST_EXPRESSION):
 880            postexpression_props_sql = self.properties(
 881                exp.Properties(
 882                    expressions=properties_locs[exp.Properties.Location.POST_EXPRESSION]
 883                ),
 884                sep=" ",
 885                prefix=" ",
 886                wrapped=False,
 887            )
 888
 889        exists_sql = " IF NOT EXISTS" if expression.args.get("exists") else ""
 890        no_schema_binding = (
 891            " WITH NO SCHEMA BINDING" if expression.args.get("no_schema_binding") else ""
 892        )
 893
 894        clone = self.sql(expression, "clone")
 895        clone = f" {clone}" if clone else ""
 896
 897        expression_sql = f"CREATE{modifiers} {kind}{exists_sql} {this}{properties_sql}{expression_sql}{postexpression_props_sql}{index_sql}{no_schema_binding}{clone}"
 898        return self.prepend_ctes(expression, expression_sql)
 899
 900    def clone_sql(self, expression: exp.Clone) -> str:
 901        this = self.sql(expression, "this")
 902        shallow = "SHALLOW " if expression.args.get("shallow") else ""
 903        keyword = "COPY" if expression.args.get("copy") and self.SUPPORTS_TABLE_COPY else "CLONE"
 904        return f"{shallow}{keyword} {this}"
 905
 906    def describe_sql(self, expression: exp.Describe) -> str:
 907        extended = " EXTENDED" if expression.args.get("extended") else ""
 908        return f"DESCRIBE{extended} {self.sql(expression, 'this')}"
 909
 910    def heredoc_sql(self, expression: exp.Heredoc) -> str:
 911        tag = self.sql(expression, "tag")
 912        return f"${tag}${self.sql(expression, 'this')}${tag}$"
 913
 914    def prepend_ctes(self, expression: exp.Expression, sql: str) -> str:
 915        with_ = self.sql(expression, "with")
 916        if with_:
 917            sql = f"{with_}{self.sep()}{sql}"
 918        return sql
 919
 920    def with_sql(self, expression: exp.With) -> str:
 921        sql = self.expressions(expression, flat=True)
 922        recursive = (
 923            "RECURSIVE "
 924            if self.CTE_RECURSIVE_KEYWORD_REQUIRED and expression.args.get("recursive")
 925            else ""
 926        )
 927
 928        return f"WITH {recursive}{sql}"
 929
 930    def cte_sql(self, expression: exp.CTE) -> str:
 931        alias = self.sql(expression, "alias")
 932        return f"{alias} AS {self.wrap(expression)}"
 933
 934    def tablealias_sql(self, expression: exp.TableAlias) -> str:
 935        alias = self.sql(expression, "this")
 936        columns = self.expressions(expression, key="columns", flat=True)
 937        columns = f"({columns})" if columns else ""
 938
 939        if columns and not self.SUPPORTS_TABLE_ALIAS_COLUMNS:
 940            columns = ""
 941            self.unsupported("Named columns are not supported in table alias.")
 942
 943        if not alias and not self.dialect.UNNEST_COLUMN_ONLY:
 944            alias = "_t"
 945
 946        return f"{alias}{columns}"
 947
 948    def bitstring_sql(self, expression: exp.BitString) -> str:
 949        this = self.sql(expression, "this")
 950        if self.dialect.BIT_START:
 951            return f"{self.dialect.BIT_START}{this}{self.dialect.BIT_END}"
 952        return f"{int(this, 2)}"
 953
 954    def hexstring_sql(self, expression: exp.HexString) -> str:
 955        this = self.sql(expression, "this")
 956        if self.dialect.HEX_START:
 957            return f"{self.dialect.HEX_START}{this}{self.dialect.HEX_END}"
 958        return f"{int(this, 16)}"
 959
 960    def bytestring_sql(self, expression: exp.ByteString) -> str:
 961        this = self.sql(expression, "this")
 962        if self.dialect.BYTE_START:
 963            return f"{self.dialect.BYTE_START}{this}{self.dialect.BYTE_END}"
 964        return this
 965
 966    def unicodestring_sql(self, expression: exp.UnicodeString) -> str:
 967        this = self.sql(expression, "this")
 968        escape = expression.args.get("escape")
 969
 970        if self.dialect.UNICODE_START:
 971            escape = f" UESCAPE {self.sql(escape)}" if escape else ""
 972            return f"{self.dialect.UNICODE_START}{this}{self.dialect.UNICODE_END}{escape}"
 973
 974        if escape:
 975            pattern = re.compile(rf"{escape.name}(\d+)")
 976        else:
 977            pattern = ESCAPED_UNICODE_RE
 978
 979        this = pattern.sub(r"\\u\1", this)
 980        return f"{self.dialect.QUOTE_START}{this}{self.dialect.QUOTE_END}"
 981
 982    def rawstring_sql(self, expression: exp.RawString) -> str:
 983        string = self.escape_str(expression.this.replace("\\", "\\\\"))
 984        return f"{self.dialect.QUOTE_START}{string}{self.dialect.QUOTE_END}"
 985
 986    def datatypeparam_sql(self, expression: exp.DataTypeParam) -> str:
 987        this = self.sql(expression, "this")
 988        specifier = self.sql(expression, "expression")
 989        specifier = f" {specifier}" if specifier and self.DATA_TYPE_SPECIFIERS_ALLOWED else ""
 990        return f"{this}{specifier}"
 991
 992    def datatype_sql(self, expression: exp.DataType) -> str:
 993        type_value = expression.this
 994
 995        if type_value == exp.DataType.Type.USERDEFINED and expression.args.get("kind"):
 996            type_sql = self.sql(expression, "kind")
 997        else:
 998            type_sql = (
 999                self.TYPE_MAPPING.get(type_value, type_value.value)
1000                if isinstance(type_value, exp.DataType.Type)
1001                else type_value
1002            )
1003
1004        nested = ""
1005        interior = self.expressions(expression, flat=True)
1006        values = ""
1007
1008        if interior:
1009            if expression.args.get("nested"):
1010                nested = f"{self.STRUCT_DELIMITER[0]}{interior}{self.STRUCT_DELIMITER[1]}"
1011                if expression.args.get("values") is not None:
1012                    delimiters = ("[", "]") if type_value == exp.DataType.Type.ARRAY else ("(", ")")
1013                    values = self.expressions(expression, key="values", flat=True)
1014                    values = f"{delimiters[0]}{values}{delimiters[1]}"
1015            elif type_value == exp.DataType.Type.INTERVAL:
1016                nested = f" {interior}"
1017            else:
1018                nested = f"({interior})"
1019
1020        type_sql = f"{type_sql}{nested}{values}"
1021        if self.TZ_TO_WITH_TIME_ZONE and type_value in (
1022            exp.DataType.Type.TIMETZ,
1023            exp.DataType.Type.TIMESTAMPTZ,
1024        ):
1025            type_sql = f"{type_sql} WITH TIME ZONE"
1026
1027        return type_sql
1028
1029    def directory_sql(self, expression: exp.Directory) -> str:
1030        local = "LOCAL " if expression.args.get("local") else ""
1031        row_format = self.sql(expression, "row_format")
1032        row_format = f" {row_format}" if row_format else ""
1033        return f"{local}DIRECTORY {self.sql(expression, 'this')}{row_format}"
1034
1035    def delete_sql(self, expression: exp.Delete) -> str:
1036        this = self.sql(expression, "this")
1037        this = f" FROM {this}" if this else ""
1038        using = self.sql(expression, "using")
1039        using = f" USING {using}" if using else ""
1040        where = self.sql(expression, "where")
1041        returning = self.sql(expression, "returning")
1042        limit = self.sql(expression, "limit")
1043        tables = self.expressions(expression, key="tables")
1044        tables = f" {tables}" if tables else ""
1045        if self.RETURNING_END:
1046            expression_sql = f"{this}{using}{where}{returning}{limit}"
1047        else:
1048            expression_sql = f"{returning}{this}{using}{where}{limit}"
1049        return self.prepend_ctes(expression, f"DELETE{tables}{expression_sql}")
1050
1051    def drop_sql(self, expression: exp.Drop) -> str:
1052        this = self.sql(expression, "this")
1053        kind = expression.args["kind"]
1054        exists_sql = " IF EXISTS " if expression.args.get("exists") else " "
1055        temporary = " TEMPORARY" if expression.args.get("temporary") else ""
1056        materialized = " MATERIALIZED" if expression.args.get("materialized") else ""
1057        cascade = " CASCADE" if expression.args.get("cascade") else ""
1058        constraints = " CONSTRAINTS" if expression.args.get("constraints") else ""
1059        purge = " PURGE" if expression.args.get("purge") else ""
1060        return (
1061            f"DROP{temporary}{materialized} {kind}{exists_sql}{this}{cascade}{constraints}{purge}"
1062        )
1063
1064    def except_sql(self, expression: exp.Except) -> str:
1065        return self.prepend_ctes(
1066            expression,
1067            self.set_operation(expression, self.except_op(expression)),
1068        )
1069
1070    def except_op(self, expression: exp.Except) -> str:
1071        return f"EXCEPT{'' if expression.args.get('distinct') else ' ALL'}"
1072
1073    def fetch_sql(self, expression: exp.Fetch) -> str:
1074        direction = expression.args.get("direction")
1075        direction = f" {direction}" if direction else ""
1076        count = expression.args.get("count")
1077        count = f" {count}" if count else ""
1078        if expression.args.get("percent"):
1079            count = f"{count} PERCENT"
1080        with_ties_or_only = "WITH TIES" if expression.args.get("with_ties") else "ONLY"
1081        return f"{self.seg('FETCH')}{direction}{count} ROWS {with_ties_or_only}"
1082
1083    def filter_sql(self, expression: exp.Filter) -> str:
1084        if self.AGGREGATE_FILTER_SUPPORTED:
1085            this = self.sql(expression, "this")
1086            where = self.sql(expression, "expression").strip()
1087            return f"{this} FILTER({where})"
1088
1089        agg = expression.this
1090        agg_arg = agg.this
1091        cond = expression.expression.this
1092        agg_arg.replace(exp.If(this=cond.copy(), true=agg_arg.copy()))
1093        return self.sql(agg)
1094
1095    def hint_sql(self, expression: exp.Hint) -> str:
1096        if not self.QUERY_HINTS:
1097            self.unsupported("Hints are not supported")
1098            return ""
1099
1100        return f" /*+ {self.expressions(expression, sep=self.QUERY_HINT_SEP).strip()} */"
1101
1102    def index_sql(self, expression: exp.Index) -> str:
1103        unique = "UNIQUE " if expression.args.get("unique") else ""
1104        primary = "PRIMARY " if expression.args.get("primary") else ""
1105        amp = "AMP " if expression.args.get("amp") else ""
1106        name = self.sql(expression, "this")
1107        name = f"{name} " if name else ""
1108        table = self.sql(expression, "table")
1109        table = f"{self.INDEX_ON} {table}" if table else ""
1110        using = self.sql(expression, "using")
1111        using = f" USING {using}" if using else ""
1112        index = "INDEX " if not table else ""
1113        columns = self.expressions(expression, key="columns", flat=True)
1114        columns = f"({columns})" if columns else ""
1115        partition_by = self.expressions(expression, key="partition_by", flat=True)
1116        partition_by = f" PARTITION BY {partition_by}" if partition_by else ""
1117        where = self.sql(expression, "where")
1118        include = self.expressions(expression, key="include", flat=True)
1119        if include:
1120            include = f" INCLUDE ({include})"
1121        return f"{unique}{primary}{amp}{index}{name}{table}{using}{columns}{include}{partition_by}{where}"
1122
1123    def identifier_sql(self, expression: exp.Identifier) -> str:
1124        text = expression.name
1125        lower = text.lower()
1126        text = lower if self.normalize and not expression.quoted else text
1127        text = text.replace(self.dialect.IDENTIFIER_END, self._escaped_identifier_end)
1128        if (
1129            expression.quoted
1130            or self.dialect.can_identify(text, self.identify)
1131            or lower in self.RESERVED_KEYWORDS
1132            or (not self.dialect.IDENTIFIERS_CAN_START_WITH_DIGIT and text[:1].isdigit())
1133        ):
1134            text = f"{self.dialect.IDENTIFIER_START}{text}{self.dialect.IDENTIFIER_END}"
1135        return text
1136
1137    def inputoutputformat_sql(self, expression: exp.InputOutputFormat) -> str:
1138        input_format = self.sql(expression, "input_format")
1139        input_format = f"INPUTFORMAT {input_format}" if input_format else ""
1140        output_format = self.sql(expression, "output_format")
1141        output_format = f"OUTPUTFORMAT {output_format}" if output_format else ""
1142        return self.sep().join((input_format, output_format))
1143
1144    def national_sql(self, expression: exp.National, prefix: str = "N") -> str:
1145        string = self.sql(exp.Literal.string(expression.name))
1146        return f"{prefix}{string}"
1147
1148    def partition_sql(self, expression: exp.Partition) -> str:
1149        return f"PARTITION({self.expressions(expression, flat=True)})"
1150
1151    def properties_sql(self, expression: exp.Properties) -> str:
1152        root_properties = []
1153        with_properties = []
1154
1155        for p in expression.expressions:
1156            p_loc = self.PROPERTIES_LOCATION[p.__class__]
1157            if p_loc == exp.Properties.Location.POST_WITH:
1158                with_properties.append(p)
1159            elif p_loc == exp.Properties.Location.POST_SCHEMA:
1160                root_properties.append(p)
1161
1162        return self.root_properties(
1163            exp.Properties(expressions=root_properties)
1164        ) + self.with_properties(exp.Properties(expressions=with_properties))
1165
1166    def root_properties(self, properties: exp.Properties) -> str:
1167        if properties.expressions:
1168            return self.sep() + self.expressions(properties, indent=False, sep=" ")
1169        return ""
1170
1171    def properties(
1172        self,
1173        properties: exp.Properties,
1174        prefix: str = "",
1175        sep: str = ", ",
1176        suffix: str = "",
1177        wrapped: bool = True,
1178    ) -> str:
1179        if properties.expressions:
1180            expressions = self.expressions(properties, sep=sep, indent=False)
1181            if expressions:
1182                expressions = self.wrap(expressions) if wrapped else expressions
1183                return f"{prefix}{' ' if prefix.strip() else ''}{expressions}{suffix}"
1184        return ""
1185
1186    def with_properties(self, properties: exp.Properties) -> str:
1187        return self.properties(properties, prefix=self.seg("WITH"))
1188
1189    def locate_properties(self, properties: exp.Properties) -> t.DefaultDict:
1190        properties_locs = defaultdict(list)
1191        for p in properties.expressions:
1192            p_loc = self.PROPERTIES_LOCATION[p.__class__]
1193            if p_loc != exp.Properties.Location.UNSUPPORTED:
1194                properties_locs[p_loc].append(p)
1195            else:
1196                self.unsupported(f"Unsupported property {p.key}")
1197
1198        return properties_locs
1199
1200    def property_name(self, expression: exp.Property, string_key: bool = False) -> str:
1201        if isinstance(expression.this, exp.Dot):
1202            return self.sql(expression, "this")
1203        return f"'{expression.name}'" if string_key else expression.name
1204
1205    def property_sql(self, expression: exp.Property) -> str:
1206        property_cls = expression.__class__
1207        if property_cls == exp.Property:
1208            return f"{self.property_name(expression)}={self.sql(expression, 'value')}"
1209
1210        property_name = exp.Properties.PROPERTY_TO_NAME.get(property_cls)
1211        if not property_name:
1212            self.unsupported(f"Unsupported property {expression.key}")
1213
1214        return f"{property_name}={self.sql(expression, 'this')}"
1215
1216    def likeproperty_sql(self, expression: exp.LikeProperty) -> str:
1217        options = " ".join(f"{e.name} {self.sql(e, 'value')}" for e in expression.expressions)
1218        options = f" {options}" if options else ""
1219        return f"LIKE {self.sql(expression, 'this')}{options}"
1220
1221    def fallbackproperty_sql(self, expression: exp.FallbackProperty) -> str:
1222        no = "NO " if expression.args.get("no") else ""
1223        protection = " PROTECTION" if expression.args.get("protection") else ""
1224        return f"{no}FALLBACK{protection}"
1225
1226    def journalproperty_sql(self, expression: exp.JournalProperty) -> str:
1227        no = "NO " if expression.args.get("no") else ""
1228        local = expression.args.get("local")
1229        local = f"{local} " if local else ""
1230        dual = "DUAL " if expression.args.get("dual") else ""
1231        before = "BEFORE " if expression.args.get("before") else ""
1232        after = "AFTER " if expression.args.get("after") else ""
1233        return f"{no}{local}{dual}{before}{after}JOURNAL"
1234
1235    def freespaceproperty_sql(self, expression: exp.FreespaceProperty) -> str:
1236        freespace = self.sql(expression, "this")
1237        percent = " PERCENT" if expression.args.get("percent") else ""
1238        return f"FREESPACE={freespace}{percent}"
1239
1240    def checksumproperty_sql(self, expression: exp.ChecksumProperty) -> str:
1241        if expression.args.get("default"):
1242            property = "DEFAULT"
1243        elif expression.args.get("on"):
1244            property = "ON"
1245        else:
1246            property = "OFF"
1247        return f"CHECKSUM={property}"
1248
1249    def mergeblockratioproperty_sql(self, expression: exp.MergeBlockRatioProperty) -> str:
1250        if expression.args.get("no"):
1251            return "NO MERGEBLOCKRATIO"
1252        if expression.args.get("default"):
1253            return "DEFAULT MERGEBLOCKRATIO"
1254
1255        percent = " PERCENT" if expression.args.get("percent") else ""
1256        return f"MERGEBLOCKRATIO={self.sql(expression, 'this')}{percent}"
1257
1258    def datablocksizeproperty_sql(self, expression: exp.DataBlocksizeProperty) -> str:
1259        default = expression.args.get("default")
1260        minimum = expression.args.get("minimum")
1261        maximum = expression.args.get("maximum")
1262        if default or minimum or maximum:
1263            if default:
1264                prop = "DEFAULT"
1265            elif minimum:
1266                prop = "MINIMUM"
1267            else:
1268                prop = "MAXIMUM"
1269            return f"{prop} DATABLOCKSIZE"
1270        units = expression.args.get("units")
1271        units = f" {units}" if units else ""
1272        return f"DATABLOCKSIZE={self.sql(expression, 'size')}{units}"
1273
1274    def blockcompressionproperty_sql(self, expression: exp.BlockCompressionProperty) -> str:
1275        autotemp = expression.args.get("autotemp")
1276        always = expression.args.get("always")
1277        default = expression.args.get("default")
1278        manual = expression.args.get("manual")
1279        never = expression.args.get("never")
1280
1281        if autotemp is not None:
1282            prop = f"AUTOTEMP({self.expressions(autotemp)})"
1283        elif always:
1284            prop = "ALWAYS"
1285        elif default:
1286            prop = "DEFAULT"
1287        elif manual:
1288            prop = "MANUAL"
1289        elif never:
1290            prop = "NEVER"
1291        return f"BLOCKCOMPRESSION={prop}"
1292
1293    def isolatedloadingproperty_sql(self, expression: exp.IsolatedLoadingProperty) -> str:
1294        no = expression.args.get("no")
1295        no = " NO" if no else ""
1296        concurrent = expression.args.get("concurrent")
1297        concurrent = " CONCURRENT" if concurrent else ""
1298
1299        for_ = ""
1300        if expression.args.get("for_all"):
1301            for_ = " FOR ALL"
1302        elif expression.args.get("for_insert"):
1303            for_ = " FOR INSERT"
1304        elif expression.args.get("for_none"):
1305            for_ = " FOR NONE"
1306        return f"WITH{no}{concurrent} ISOLATED LOADING{for_}"
1307
1308    def partitionboundspec_sql(self, expression: exp.PartitionBoundSpec) -> str:
1309        if isinstance(expression.this, list):
1310            return f"IN ({self.expressions(expression, key='this', flat=True)})"
1311        if expression.this:
1312            modulus = self.sql(expression, "this")
1313            remainder = self.sql(expression, "expression")
1314            return f"WITH (MODULUS {modulus}, REMAINDER {remainder})"
1315
1316        from_expressions = self.expressions(expression, key="from_expressions", flat=True)
1317        to_expressions = self.expressions(expression, key="to_expressions", flat=True)
1318        return f"FROM ({from_expressions}) TO ({to_expressions})"
1319
1320    def partitionedofproperty_sql(self, expression: exp.PartitionedOfProperty) -> str:
1321        this = self.sql(expression, "this")
1322
1323        for_values_or_default = expression.expression
1324        if isinstance(for_values_or_default, exp.PartitionBoundSpec):
1325            for_values_or_default = f" FOR VALUES {self.sql(for_values_or_default)}"
1326        else:
1327            for_values_or_default = " DEFAULT"
1328
1329        return f"PARTITION OF {this}{for_values_or_default}"
1330
1331    def lockingproperty_sql(self, expression: exp.LockingProperty) -> str:
1332        kind = expression.args.get("kind")
1333        this = f" {self.sql(expression, 'this')}" if expression.this else ""
1334        for_or_in = expression.args.get("for_or_in")
1335        for_or_in = f" {for_or_in}" if for_or_in else ""
1336        lock_type = expression.args.get("lock_type")
1337        override = " OVERRIDE" if expression.args.get("override") else ""
1338        return f"LOCKING {kind}{this}{for_or_in} {lock_type}{override}"
1339
1340    def withdataproperty_sql(self, expression: exp.WithDataProperty) -> str:
1341        data_sql = f"WITH {'NO ' if expression.args.get('no') else ''}DATA"
1342        statistics = expression.args.get("statistics")
1343        statistics_sql = ""
1344        if statistics is not None:
1345            statistics_sql = f" AND {'NO ' if not statistics else ''}STATISTICS"
1346        return f"{data_sql}{statistics_sql}"
1347
1348    def withsystemversioningproperty_sql(self, expression: exp.WithSystemVersioningProperty) -> str:
1349        sql = "WITH(SYSTEM_VERSIONING=ON"
1350
1351        if expression.this:
1352            history_table = self.sql(expression, "this")
1353            sql = f"{sql}(HISTORY_TABLE={history_table}"
1354
1355            if expression.expression:
1356                data_consistency_check = self.sql(expression, "expression")
1357                sql = f"{sql}, DATA_CONSISTENCY_CHECK={data_consistency_check}"
1358
1359            sql = f"{sql})"
1360
1361        return f"{sql})"
1362
1363    def insert_sql(self, expression: exp.Insert) -> str:
1364        overwrite = expression.args.get("overwrite")
1365
1366        if isinstance(expression.this, exp.Directory):
1367            this = " OVERWRITE" if overwrite else " INTO"
1368        else:
1369            this = self.INSERT_OVERWRITE if overwrite else " INTO"
1370
1371        alternative = expression.args.get("alternative")
1372        alternative = f" OR {alternative}" if alternative else ""
1373        ignore = " IGNORE" if expression.args.get("ignore") else ""
1374
1375        this = f"{this} {self.sql(expression, 'this')}"
1376
1377        exists = " IF EXISTS" if expression.args.get("exists") else ""
1378        partition_sql = (
1379            f" {self.sql(expression, 'partition')}" if expression.args.get("partition") else ""
1380        )
1381        where = self.sql(expression, "where")
1382        where = f"{self.sep()}REPLACE WHERE {where}" if where else ""
1383        expression_sql = f"{self.sep()}{self.sql(expression, 'expression')}"
1384        conflict = self.sql(expression, "conflict")
1385        by_name = " BY NAME" if expression.args.get("by_name") else ""
1386        returning = self.sql(expression, "returning")
1387
1388        if self.RETURNING_END:
1389            expression_sql = f"{expression_sql}{conflict}{returning}"
1390        else:
1391            expression_sql = f"{returning}{expression_sql}{conflict}"
1392
1393        sql = f"INSERT{alternative}{ignore}{this}{by_name}{exists}{partition_sql}{where}{expression_sql}"
1394        return self.prepend_ctes(expression, sql)
1395
1396    def intersect_sql(self, expression: exp.Intersect) -> str:
1397        return self.prepend_ctes(
1398            expression,
1399            self.set_operation(expression, self.intersect_op(expression)),
1400        )
1401
1402    def intersect_op(self, expression: exp.Intersect) -> str:
1403        return f"INTERSECT{'' if expression.args.get('distinct') else ' ALL'}"
1404
1405    def introducer_sql(self, expression: exp.Introducer) -> str:
1406        return f"{self.sql(expression, 'this')} {self.sql(expression, 'expression')}"
1407
1408    def kill_sql(self, expression: exp.Kill) -> str:
1409        kind = self.sql(expression, "kind")
1410        kind = f" {kind}" if kind else ""
1411        this = self.sql(expression, "this")
1412        this = f" {this}" if this else ""
1413        return f"KILL{kind}{this}"
1414
1415    def pseudotype_sql(self, expression: exp.PseudoType) -> str:
1416        return expression.name
1417
1418    def objectidentifier_sql(self, expression: exp.ObjectIdentifier) -> str:
1419        return expression.name
1420
1421    def onconflict_sql(self, expression: exp.OnConflict) -> str:
1422        conflict = "ON DUPLICATE KEY" if expression.args.get("duplicate") else "ON CONFLICT"
1423        constraint = self.sql(expression, "constraint")
1424        if constraint:
1425            constraint = f"ON CONSTRAINT {constraint}"
1426        key = self.expressions(expression, key="key", flat=True)
1427        do = "" if expression.args.get("duplicate") else " DO "
1428        nothing = "NOTHING" if expression.args.get("nothing") else ""
1429        expressions = self.expressions(expression, flat=True)
1430        set_keyword = "SET " if self.DUPLICATE_KEY_UPDATE_WITH_SET else ""
1431        if expressions:
1432            expressions = f"UPDATE {set_keyword}{expressions}"
1433        return f"{self.seg(conflict)} {constraint}{key}{do}{nothing}{expressions}"
1434
1435    def returning_sql(self, expression: exp.Returning) -> str:
1436        return f"{self.seg('RETURNING')} {self.expressions(expression, flat=True)}"
1437
1438    def rowformatdelimitedproperty_sql(self, expression: exp.RowFormatDelimitedProperty) -> str:
1439        fields = expression.args.get("fields")
1440        fields = f" FIELDS TERMINATED BY {fields}" if fields else ""
1441        escaped = expression.args.get("escaped")
1442        escaped = f" ESCAPED BY {escaped}" if escaped else ""
1443        items = expression.args.get("collection_items")
1444        items = f" COLLECTION ITEMS TERMINATED BY {items}" if items else ""
1445        keys = expression.args.get("map_keys")
1446        keys = f" MAP KEYS TERMINATED BY {keys}" if keys else ""
1447        lines = expression.args.get("lines")
1448        lines = f" LINES TERMINATED BY {lines}" if lines else ""
1449        null = expression.args.get("null")
1450        null = f" NULL DEFINED AS {null}" if null else ""
1451        return f"ROW FORMAT DELIMITED{fields}{escaped}{items}{keys}{lines}{null}"
1452
1453    def withtablehint_sql(self, expression: exp.WithTableHint) -> str:
1454        return f"WITH ({self.expressions(expression, flat=True)})"
1455
1456    def indextablehint_sql(self, expression: exp.IndexTableHint) -> str:
1457        this = f"{self.sql(expression, 'this')} INDEX"
1458        target = self.sql(expression, "target")
1459        target = f" FOR {target}" if target else ""
1460        return f"{this}{target} ({self.expressions(expression, flat=True)})"
1461
1462    def historicaldata_sql(self, expression: exp.HistoricalData) -> str:
1463        this = self.sql(expression, "this")
1464        kind = self.sql(expression, "kind")
1465        expr = self.sql(expression, "expression")
1466        return f"{this} ({kind} => {expr})"
1467
1468    def table_sql(self, expression: exp.Table, sep: str = " AS ") -> str:
1469        table = ".".join(
1470            self.sql(part)
1471            for part in (
1472                expression.args.get("catalog"),
1473                expression.args.get("db"),
1474                expression.args.get("this"),
1475            )
1476            if part is not None
1477        )
1478
1479        version = self.sql(expression, "version")
1480        version = f" {version}" if version else ""
1481        alias = self.sql(expression, "alias")
1482        alias = f"{sep}{alias}" if alias else ""
1483        hints = self.expressions(expression, key="hints", sep=" ")
1484        hints = f" {hints}" if hints and self.TABLE_HINTS else ""
1485        pivots = self.expressions(expression, key="pivots", sep=" ", flat=True)
1486        pivots = f" {pivots}" if pivots else ""
1487        joins = self.expressions(expression, key="joins", sep="", skip_first=True)
1488        laterals = self.expressions(expression, key="laterals", sep="")
1489
1490        file_format = self.sql(expression, "format")
1491        if file_format:
1492            pattern = self.sql(expression, "pattern")
1493            pattern = f", PATTERN => {pattern}" if pattern else ""
1494            file_format = f" (FILE_FORMAT => {file_format}{pattern})"
1495
1496        ordinality = expression.args.get("ordinality") or ""
1497        if ordinality:
1498            ordinality = f" WITH ORDINALITY{alias}"
1499            alias = ""
1500
1501        when = self.sql(expression, "when")
1502        if when:
1503            table = f"{table} {when}"
1504
1505        return f"{table}{version}{file_format}{alias}{hints}{pivots}{joins}{laterals}{ordinality}"
1506
1507    def tablesample_sql(
1508        self,
1509        expression: exp.TableSample,
1510        sep: str = " AS ",
1511        tablesample_keyword: t.Optional[str] = None,
1512    ) -> str:
1513        if self.dialect.ALIAS_POST_TABLESAMPLE and expression.this and expression.this.alias:
1514            table = expression.this.copy()
1515            table.set("alias", None)
1516            this = self.sql(table)
1517            alias = f"{sep}{self.sql(expression.this, 'alias')}"
1518        else:
1519            this = self.sql(expression, "this")
1520            alias = ""
1521
1522        method = self.sql(expression, "method")
1523        method = f"{method} " if method and self.TABLESAMPLE_WITH_METHOD else ""
1524        numerator = self.sql(expression, "bucket_numerator")
1525        denominator = self.sql(expression, "bucket_denominator")
1526        field = self.sql(expression, "bucket_field")
1527        field = f" ON {field}" if field else ""
1528        bucket = f"BUCKET {numerator} OUT OF {denominator}{field}" if numerator else ""
1529        seed = self.sql(expression, "seed")
1530        seed = f" {self.TABLESAMPLE_SEED_KEYWORD} ({seed})" if seed else ""
1531
1532        size = self.sql(expression, "size")
1533        if size and self.TABLESAMPLE_SIZE_IS_ROWS:
1534            size = f"{size} ROWS"
1535
1536        percent = self.sql(expression, "percent")
1537        if percent and not self.dialect.TABLESAMPLE_SIZE_IS_PERCENT:
1538            percent = f"{percent} PERCENT"
1539
1540        expr = f"{bucket}{percent}{size}"
1541        if self.TABLESAMPLE_REQUIRES_PARENS:
1542            expr = f"({expr})"
1543
1544        return (
1545            f"{this} {tablesample_keyword or self.TABLESAMPLE_KEYWORDS} {method}{expr}{seed}{alias}"
1546        )
1547
1548    def pivot_sql(self, expression: exp.Pivot) -> str:
1549        expressions = self.expressions(expression, flat=True)
1550
1551        if expression.this:
1552            this = self.sql(expression, "this")
1553            if not expressions:
1554                return f"UNPIVOT {this}"
1555
1556            on = f"{self.seg('ON')} {expressions}"
1557            using = self.expressions(expression, key="using", flat=True)
1558            using = f"{self.seg('USING')} {using}" if using else ""
1559            group = self.sql(expression, "group")
1560            return f"PIVOT {this}{on}{using}{group}"
1561
1562        alias = self.sql(expression, "alias")
1563        alias = f" AS {alias}" if alias else ""
1564        direction = "UNPIVOT" if expression.unpivot else "PIVOT"
1565        field = self.sql(expression, "field")
1566        include_nulls = expression.args.get("include_nulls")
1567        if include_nulls is not None:
1568            nulls = " INCLUDE NULLS " if include_nulls else " EXCLUDE NULLS "
1569        else:
1570            nulls = ""
1571        return f"{direction}{nulls}({expressions} FOR {field}){alias}"
1572
1573    def version_sql(self, expression: exp.Version) -> str:
1574        this = f"FOR {expression.name}"
1575        kind = expression.text("kind")
1576        expr = self.sql(expression, "expression")
1577        return f"{this} {kind} {expr}"
1578
1579    def tuple_sql(self, expression: exp.Tuple) -> str:
1580        return f"({self.expressions(expression, flat=True)})"
1581
1582    def update_sql(self, expression: exp.Update) -> str:
1583        this = self.sql(expression, "this")
1584        set_sql = self.expressions(expression, flat=True)
1585        from_sql = self.sql(expression, "from")
1586        where_sql = self.sql(expression, "where")
1587        returning = self.sql(expression, "returning")
1588        order = self.sql(expression, "order")
1589        limit = self.sql(expression, "limit")
1590        if self.RETURNING_END:
1591            expression_sql = f"{from_sql}{where_sql}{returning}"
1592        else:
1593            expression_sql = f"{returning}{from_sql}{where_sql}"
1594        sql = f"UPDATE {this} SET {set_sql}{expression_sql}{order}{limit}"
1595        return self.prepend_ctes(expression, sql)
1596
1597    def values_sql(self, expression: exp.Values) -> str:
1598        # The VALUES clause is still valid in an `INSERT INTO ..` statement, for example
1599        if self.VALUES_AS_TABLE or not expression.find_ancestor(exp.From, exp.Join):
1600            args = self.expressions(expression)
1601            alias = self.sql(expression, "alias")
1602            values = f"VALUES{self.seg('')}{args}"
1603            values = (
1604                f"({values})"
1605                if self.WRAP_DERIVED_VALUES and (alias or isinstance(expression.parent, exp.From))
1606                else values
1607            )
1608            return f"{values} AS {alias}" if alias else values
1609
1610        # Converts `VALUES...` expression into a series of select unions.
1611        alias_node = expression.args.get("alias")
1612        column_names = alias_node and alias_node.columns
1613
1614        selects: t.List[exp.Subqueryable] = []
1615
1616        for i, tup in enumerate(expression.expressions):
1617            row = tup.expressions
1618
1619            if i == 0 and column_names:
1620                row = [
1621                    exp.alias_(value, column_name) for value, column_name in zip(row, column_names)
1622                ]
1623
1624            selects.append(exp.Select(expressions=row))
1625
1626        if self.pretty:
1627            # This may result in poor performance for large-cardinality `VALUES` tables, due to
1628            # the deep nesting of the resulting exp.Unions. If this is a problem, either increase
1629            # `sys.setrecursionlimit` to avoid RecursionErrors, or don't set `pretty`.
1630            subqueryable = reduce(lambda x, y: exp.union(x, y, distinct=False, copy=False), selects)
1631            return self.subquery_sql(
1632                subqueryable.subquery(alias_node and alias_node.this, copy=False)
1633            )
1634
1635        alias = f" AS {self.sql(alias_node, 'this')}" if alias_node else ""
1636        unions = " UNION ALL ".join(self.sql(select) for select in selects)
1637        return f"({unions}){alias}"
1638
1639    def var_sql(self, expression: exp.Var) -> str:
1640        return self.sql(expression, "this")
1641
1642    def into_sql(self, expression: exp.Into) -> str:
1643        temporary = " TEMPORARY" if expression.args.get("temporary") else ""
1644        unlogged = " UNLOGGED" if expression.args.get("unlogged") else ""
1645        return f"{self.seg('INTO')}{temporary or unlogged} {self.sql(expression, 'this')}"
1646
1647    def from_sql(self, expression: exp.From) -> str:
1648        return f"{self.seg('FROM')} {self.sql(expression, 'this')}"
1649
1650    def group_sql(self, expression: exp.Group) -> str:
1651        group_by = self.op_expressions("GROUP BY", expression)
1652
1653        if expression.args.get("all"):
1654            return f"{group_by} ALL"
1655
1656        grouping_sets = self.expressions(expression, key="grouping_sets", indent=False)
1657        grouping_sets = (
1658            f"{self.seg('GROUPING SETS')} {self.wrap(grouping_sets)}" if grouping_sets else ""
1659        )
1660
1661        cube = expression.args.get("cube", [])
1662        if seq_get(cube, 0) is True:
1663            return f"{group_by}{self.seg('WITH CUBE')}"
1664        else:
1665            cube_sql = self.expressions(expression, key="cube", indent=False)
1666            cube_sql = f"{self.seg('CUBE')} {self.wrap(cube_sql)}" if cube_sql else ""
1667
1668        rollup = expression.args.get("rollup", [])
1669        if seq_get(rollup, 0) is True:
1670            return f"{group_by}{self.seg('WITH ROLLUP')}"
1671        else:
1672            rollup_sql = self.expressions(expression, key="rollup", indent=False)
1673            rollup_sql = f"{self.seg('ROLLUP')} {self.wrap(rollup_sql)}" if rollup_sql else ""
1674
1675        groupings = csv(
1676            grouping_sets,
1677            cube_sql,
1678            rollup_sql,
1679            self.seg("WITH TOTALS") if expression.args.get("totals") else "",
1680            sep=self.GROUPINGS_SEP,
1681        )
1682
1683        if expression.args.get("expressions") and groupings:
1684            group_by = f"{group_by}{self.GROUPINGS_SEP}"
1685
1686        return f"{group_by}{groupings}"
1687
1688    def having_sql(self, expression: exp.Having) -> str:
1689        this = self.indent(self.sql(expression, "this"))
1690        return f"{self.seg('HAVING')}{self.sep()}{this}"
1691
1692    def connect_sql(self, expression: exp.Connect) -> str:
1693        start = self.sql(expression, "start")
1694        start = self.seg(f"START WITH {start}") if start else ""
1695        connect = self.sql(expression, "connect")
1696        connect = self.seg(f"CONNECT BY {connect}")
1697        return start + connect
1698
1699    def prior_sql(self, expression: exp.Prior) -> str:
1700        return f"PRIOR {self.sql(expression, 'this')}"
1701
1702    def join_sql(self, expression: exp.Join) -> str:
1703        if not self.SEMI_ANTI_JOIN_WITH_SIDE and expression.kind in ("SEMI", "ANTI"):
1704            side = None
1705        else:
1706            side = expression.side
1707
1708        op_sql = " ".join(
1709            op
1710            for op in (
1711                expression.method,
1712                "GLOBAL" if expression.args.get("global") else None,
1713                side,
1714                expression.kind,
1715                expression.hint if self.JOIN_HINTS else None,
1716            )
1717            if op
1718        )
1719        on_sql = self.sql(expression, "on")
1720        using = expression.args.get("using")
1721
1722        if not on_sql and using:
1723            on_sql = csv(*(self.sql(column) for column in using))
1724
1725        this = expression.this
1726        this_sql = self.sql(this)
1727
1728        if on_sql:
1729            on_sql = self.indent(on_sql, skip_first=True)
1730            space = self.seg(" " * self.pad) if self.pretty else " "
1731            if using:
1732                on_sql = f"{space}USING ({on_sql})"
1733            else:
1734                on_sql = f"{space}ON {on_sql}"
1735        elif not op_sql:
1736            if isinstance(this, exp.Lateral) and this.args.get("cross_apply") is not None:
1737                return f" {this_sql}"
1738
1739            return f", {this_sql}"
1740
1741        op_sql = f"{op_sql} JOIN" if op_sql else "JOIN"
1742        return f"{self.seg(op_sql)} {this_sql}{on_sql}"
1743
1744    def lambda_sql(self, expression: exp.Lambda, arrow_sep: str = "->") -> str:
1745        args = self.expressions(expression, flat=True)
1746        args = f"({args})" if len(args.split(",")) > 1 else args
1747        return f"{args} {arrow_sep} {self.sql(expression, 'this')}"
1748
1749    def lateral_op(self, expression: exp.Lateral) -> str:
1750        cross_apply = expression.args.get("cross_apply")
1751
1752        # https://www.mssqltips.com/sqlservertip/1958/sql-server-cross-apply-and-outer-apply/
1753        if cross_apply is True:
1754            op = "INNER JOIN "
1755        elif cross_apply is False:
1756            op = "LEFT JOIN "
1757        else:
1758            op = ""
1759
1760        return f"{op}LATERAL"
1761
1762    def lateral_sql(self, expression: exp.Lateral) -> str:
1763        this = self.sql(expression, "this")
1764
1765        if expression.args.get("view"):
1766            alias = expression.args["alias"]
1767            columns = self.expressions(alias, key="columns", flat=True)
1768            table = f" {alias.name}" if alias.name else ""
1769            columns = f" AS {columns}" if columns else ""
1770            op_sql = self.seg(f"LATERAL VIEW{' OUTER' if expression.args.get('outer') else ''}")
1771            return f"{op_sql}{self.sep()}{this}{table}{columns}"
1772
1773        alias = self.sql(expression, "alias")
1774        alias = f" AS {alias}" if alias else ""
1775        return f"{self.lateral_op(expression)} {this}{alias}"
1776
1777    def limit_sql(self, expression: exp.Limit, top: bool = False) -> str:
1778        this = self.sql(expression, "this")
1779
1780        args = [
1781            self._simplify_unless_literal(e) if self.LIMIT_ONLY_LITERALS else e
1782            for e in (expression.args.get(k) for k in ("offset", "expression"))
1783            if e
1784        ]
1785
1786        args_sql = ", ".join(self.sql(e) for e in args)
1787        args_sql = f"({args_sql})" if any(top and not e.is_number for e in args) else args_sql
1788        return f"{this}{self.seg('TOP' if top else 'LIMIT')} {args_sql}"
1789
1790    def offset_sql(self, expression: exp.Offset) -> str:
1791        this = self.sql(expression, "this")
1792        expression = expression.expression
1793        expression = (
1794            self._simplify_unless_literal(expression) if self.LIMIT_ONLY_LITERALS else expression
1795        )
1796        return f"{this}{self.seg('OFFSET')} {self.sql(expression)}"
1797
1798    def setitem_sql(self, expression: exp.SetItem) -> str:
1799        kind = self.sql(expression, "kind")
1800        kind = f"{kind} " if kind else ""
1801        this = self.sql(expression, "this")
1802        expressions = self.expressions(expression)
1803        collate = self.sql(expression, "collate")
1804        collate = f" COLLATE {collate}" if collate else ""
1805        global_ = "GLOBAL " if expression.args.get("global") else ""
1806        return f"{global_}{kind}{this}{expressions}{collate}"
1807
1808    def set_sql(self, expression: exp.Set) -> str:
1809        expressions = (
1810            f" {self.expressions(expression, flat=True)}" if expression.expressions else ""
1811        )
1812        tag = " TAG" if expression.args.get("tag") else ""
1813        return f"{'UNSET' if expression.args.get('unset') else 'SET'}{tag}{expressions}"
1814
1815    def pragma_sql(self, expression: exp.Pragma) -> str:
1816        return f"PRAGMA {self.sql(expression, 'this')}"
1817
1818    def lock_sql(self, expression: exp.Lock) -> str:
1819        if not self.LOCKING_READS_SUPPORTED:
1820            self.unsupported("Locking reads using 'FOR UPDATE/SHARE' are not supported")
1821            return ""
1822
1823        lock_type = "FOR UPDATE" if expression.args["update"] else "FOR SHARE"
1824        expressions = self.expressions(expression, flat=True)
1825        expressions = f" OF {expressions}" if expressions else ""
1826        wait = expression.args.get("wait")
1827
1828        if wait is not None:
1829            if isinstance(wait, exp.Literal):
1830                wait = f" WAIT {self.sql(wait)}"
1831            else:
1832                wait = " NOWAIT" if wait else " SKIP LOCKED"
1833
1834        return f"{lock_type}{expressions}{wait or ''}"
1835
1836    def literal_sql(self, expression: exp.Literal) -> str:
1837        text = expression.this or ""
1838        if expression.is_string:
1839            text = f"{self.dialect.QUOTE_START}{self.escape_str(text)}{self.dialect.QUOTE_END}"
1840        return text
1841
1842    def escape_str(self, text: str) -> str:
1843        text = text.replace(self.dialect.QUOTE_END, self._escaped_quote_end)
1844        if self.dialect.INVERSE_ESCAPE_SEQUENCES:
1845            text = "".join(self.dialect.INVERSE_ESCAPE_SEQUENCES.get(ch, ch) for ch in text)
1846        elif self.pretty:
1847            text = text.replace("\n", self.SENTINEL_LINE_BREAK)
1848        return text
1849
1850    def loaddata_sql(self, expression: exp.LoadData) -> str:
1851        local = " LOCAL" if expression.args.get("local") else ""
1852        inpath = f" INPATH {self.sql(expression, 'inpath')}"
1853        overwrite = " OVERWRITE" if expression.args.get("overwrite") else ""
1854        this = f" INTO TABLE {self.sql(expression, 'this')}"
1855        partition = self.sql(expression, "partition")
1856        partition = f" {partition}" if partition else ""
1857        input_format = self.sql(expression, "input_format")
1858        input_format = f" INPUTFORMAT {input_format}" if input_format else ""
1859        serde = self.sql(expression, "serde")
1860        serde = f" SERDE {serde}" if serde else ""
1861        return f"LOAD DATA{local}{inpath}{overwrite}{this}{partition}{input_format}{serde}"
1862
1863    def null_sql(self, *_) -> str:
1864        return "NULL"
1865
1866    def boolean_sql(self, expression: exp.Boolean) -> str:
1867        return "TRUE" if expression.this else "FALSE"
1868
1869    def order_sql(self, expression: exp.Order, flat: bool = False) -> str:
1870        this = self.sql(expression, "this")
1871        this = f"{this} " if this else this
1872        siblings = "SIBLINGS " if expression.args.get("siblings") else ""
1873        order = self.op_expressions(f"{this}ORDER {siblings}BY", expression, flat=this or flat)  # type: ignore
1874        interpolated_values = [
1875            f"{self.sql(named_expression, 'alias')} AS {self.sql(named_expression, 'this')}"
1876            for named_expression in expression.args.get("interpolate") or []
1877        ]
1878        interpolate = (
1879            f" INTERPOLATE ({', '.join(interpolated_values)})" if interpolated_values else ""
1880        )
1881        return f"{order}{interpolate}"
1882
1883    def withfill_sql(self, expression: exp.WithFill) -> str:
1884        from_sql = self.sql(expression, "from")
1885        from_sql = f" FROM {from_sql}" if from_sql else ""
1886        to_sql = self.sql(expression, "to")
1887        to_sql = f" TO {to_sql}" if to_sql else ""
1888        step_sql = self.sql(expression, "step")
1889        step_sql = f" STEP {step_sql}" if step_sql else ""
1890        return f"WITH FILL{from_sql}{to_sql}{step_sql}"
1891
1892    def cluster_sql(self, expression: exp.Cluster) -> str:
1893        return self.op_expressions("CLUSTER BY", expression)
1894
1895    def distribute_sql(self, expression: exp.Distribute) -> str:
1896        return self.op_expressions("DISTRIBUTE BY", expression)
1897
1898    def sort_sql(self, expression: exp.Sort) -> str:
1899        return self.op_expressions("SORT BY", expression)
1900
1901    def ordered_sql(self, expression: exp.Ordered) -> str:
1902        desc = expression.args.get("desc")
1903        asc = not desc
1904
1905        nulls_first = expression.args.get("nulls_first")
1906        nulls_last = not nulls_first
1907        nulls_are_large = self.dialect.NULL_ORDERING == "nulls_are_large"
1908        nulls_are_small = self.dialect.NULL_ORDERING == "nulls_are_small"
1909        nulls_are_last = self.dialect.NULL_ORDERING == "nulls_are_last"
1910
1911        this = self.sql(expression, "this")
1912
1913        sort_order = " DESC" if desc else (" ASC" if desc is False else "")
1914        nulls_sort_change = ""
1915        if nulls_first and (
1916            (asc and nulls_are_large) or (desc and nulls_are_small) or nulls_are_last
1917        ):
1918            nulls_sort_change = " NULLS FIRST"
1919        elif (
1920            nulls_last
1921            and ((asc and nulls_are_small) or (desc and nulls_are_large))
1922            and not nulls_are_last
1923        ):
1924            nulls_sort_change = " NULLS LAST"
1925
1926        # If the NULLS FIRST/LAST clause is unsupported, we add another sort key to simulate it
1927        if nulls_sort_change and not self.NULL_ORDERING_SUPPORTED:
1928            window = expression.find_ancestor(exp.Window, exp.Select)
1929            if isinstance(window, exp.Window) and window.args.get("spec"):
1930                self.unsupported(
1931                    f"'{nulls_sort_change.strip()}' translation not supported in window functions"
1932                )
1933                nulls_sort_change = ""
1934            elif self.NULL_ORDERING_SUPPORTED is None:
1935                if expression.this.is_int:
1936                    self.unsupported(
1937                        f"'{nulls_sort_change.strip()}' translation not supported with positional ordering"
1938                    )
1939                else:
1940                    null_sort_order = " DESC" if nulls_sort_change == " NULLS FIRST" else ""
1941                    this = f"CASE WHEN {this} IS NULL THEN 1 ELSE 0 END{null_sort_order}, {this}"
1942                nulls_sort_change = ""
1943
1944        with_fill = self.sql(expression, "with_fill")
1945        with_fill = f" {with_fill}" if with_fill else ""
1946
1947        return f"{this}{sort_order}{nulls_sort_change}{with_fill}"
1948
1949    def matchrecognize_sql(self, expression: exp.MatchRecognize) -> str:
1950        partition = self.partition_by_sql(expression)
1951        order = self.sql(expression, "order")
1952        measures = self.expressions(expression, key="measures")
1953        measures = self.seg(f"MEASURES{self.seg(measures)}") if measures else ""
1954        rows = self.sql(expression, "rows")
1955        rows = self.seg(rows) if rows else ""
1956        after = self.sql(expression, "after")
1957        after = self.seg(after) if after else ""
1958        pattern = self.sql(expression, "pattern")
1959        pattern = self.seg(f"PATTERN ({pattern})") if pattern else ""
1960        definition_sqls = [
1961            f"{self.sql(definition, 'alias')} AS {self.sql(definition, 'this')}"
1962            for definition in expression.args.get("define", [])
1963        ]
1964        definitions = self.expressions(sqls=definition_sqls)
1965        define = self.seg(f"DEFINE{self.seg(definitions)}") if definitions else ""
1966        body = "".join(
1967            (
1968                partition,
1969                order,
1970                measures,
1971                rows,
1972                after,
1973                pattern,
1974                define,
1975            )
1976        )
1977        alias = self.sql(expression, "alias")
1978        alias = f" {alias}" if alias else ""
1979        return f"{self.seg('MATCH_RECOGNIZE')} {self.wrap(body)}{alias}"
1980
1981    def query_modifiers(self, expression: exp.Expression, *sqls: str) -> str:
1982        limit: t.Optional[exp.Fetch | exp.Limit] = expression.args.get("limit")
1983
1984        # If the limit is generated as TOP, we need to ensure it's not generated twice
1985        with_offset_limit_modifiers = not isinstance(limit, exp.Limit) or not self.LIMIT_IS_TOP
1986
1987        if self.LIMIT_FETCH == "LIMIT" and isinstance(limit, exp.Fetch):
1988            limit = exp.Limit(expression=exp.maybe_copy(limit.args.get("count")))
1989        elif self.LIMIT_FETCH == "FETCH" and isinstance(limit, exp.Limit):
1990            limit = exp.Fetch(direction="FIRST", count=exp.maybe_copy(limit.expression))
1991
1992        fetch = isinstance(limit, exp.Fetch)
1993
1994        offset_limit_modifiers = (
1995            self.offset_limit_modifiers(expression, fetch, limit)
1996            if with_offset_limit_modifiers
1997            else []
1998        )
1999
2000        return csv(
2001            *sqls,
2002            *[self.sql(join) for join in expression.args.get("joins") or []],
2003            self.sql(expression, "connect"),
2004            self.sql(expression, "match"),
2005            *[self.sql(lateral) for lateral in expression.args.get("laterals") or []],
2006            self.sql(expression, "where"),
2007            self.sql(expression, "group"),
2008            self.sql(expression, "having"),
2009            *self.after_having_modifiers(expression),
2010            self.sql(expression, "order"),
2011            *offset_limit_modifiers,
2012            *self.after_limit_modifiers(expression),
2013            sep="",
2014        )
2015
2016    def offset_limit_modifiers(
2017        self, expression: exp.Expression, fetch: bool, limit: t.Optional[exp.Fetch | exp.Limit]
2018    ) -> t.List[str]:
2019        return [
2020            self.sql(expression, "offset") if fetch else self.sql(limit),
2021            self.sql(limit) if fetch else self.sql(expression, "offset"),
2022        ]
2023
2024    def after_having_modifiers(self, expression: exp.Expression) -> t.List[str]:
2025        return [
2026            self.sql(expression, "qualify"),
2027            self.seg("WINDOW ") + self.expressions(expression, key="windows", flat=True)
2028            if expression.args.get("windows")
2029            else "",
2030            self.sql(expression, "distribute"),
2031            self.sql(expression, "sort"),
2032            self.sql(expression, "cluster"),
2033        ]
2034
2035    def after_limit_modifiers(self, expression: exp.Expression) -> t.List[str]:
2036        locks = self.expressions(expression, key="locks", sep=" ")
2037        locks = f" {locks}" if locks else ""
2038        return [locks, self.sql(expression, "sample")]
2039
2040    def select_sql(self, expression: exp.Select) -> str:
2041        into = expression.args.get("into")
2042        if not self.SUPPORTS_SELECT_INTO and into:
2043            into.pop()
2044
2045        hint = self.sql(expression, "hint")
2046        distinct = self.sql(expression, "distinct")
2047        distinct = f" {distinct}" if distinct else ""
2048        kind = self.sql(expression, "kind")
2049        limit = expression.args.get("limit")
2050        top = (
2051            self.limit_sql(limit, top=True)
2052            if isinstance(limit, exp.Limit) and self.LIMIT_IS_TOP
2053            else ""
2054        )
2055
2056        expressions = self.expressions(expression)
2057
2058        if kind:
2059            if kind in self.SELECT_KINDS:
2060                kind = f" AS {kind}"
2061            else:
2062                if kind == "STRUCT":
2063                    expressions = self.expressions(
2064                        sqls=[
2065                            self.sql(
2066                                exp.Struct(
2067                                    expressions=[
2068                                        exp.column(e.output_name).eq(
2069                                            e.this if isinstance(e, exp.Alias) else e
2070                                        )
2071                                        for e in expression.expressions
2072                                    ]
2073                                )
2074                            )
2075                        ]
2076                    )
2077                kind = ""
2078
2079        # We use LIMIT_IS_TOP as a proxy for whether DISTINCT should go first because tsql and Teradata
2080        # are the only dialects that use LIMIT_IS_TOP and both place DISTINCT first.
2081        top_distinct = f"{distinct}{hint}{top}" if self.LIMIT_IS_TOP else f"{top}{hint}{distinct}"
2082        expressions = f"{self.sep()}{expressions}" if expressions else expressions
2083        sql = self.query_modifiers(
2084            expression,
2085            f"SELECT{top_distinct}{kind}{expressions}",
2086            self.sql(expression, "into", comment=False),
2087            self.sql(expression, "from", comment=False),
2088        )
2089
2090        sql = self.prepend_ctes(expression, sql)
2091
2092        if not self.SUPPORTS_SELECT_INTO and into:
2093            if into.args.get("temporary"):
2094                table_kind = " TEMPORARY"
2095            elif self.SUPPORTS_UNLOGGED_TABLES and into.args.get("unlogged"):
2096                table_kind = " UNLOGGED"
2097            else:
2098                table_kind = ""
2099            sql = f"CREATE{table_kind} TABLE {self.sql(into.this)} AS {sql}"
2100
2101        return sql
2102
2103    def schema_sql(self, expression: exp.Schema) -> str:
2104        this = self.sql(expression, "this")
2105        sql = self.schema_columns_sql(expression)
2106        return f"{this} {sql}" if this and sql else this or sql
2107
2108    def schema_columns_sql(self, expression: exp.Schema) -> str:
2109        if expression.expressions:
2110            return f"({self.sep('')}{self.expressions(expression)}{self.seg(')', sep='')}"
2111        return ""
2112
2113    def star_sql(self, expression: exp.Star) -> str:
2114        except_ = self.expressions(expression, key="except", flat=True)
2115        except_ = f"{self.seg(self.STAR_MAPPING['except'])} ({except_})" if except_ else ""
2116        replace = self.expressions(expression, key="replace", flat=True)
2117        replace = f"{self.seg(self.STAR_MAPPING['replace'])} ({replace})" if replace else ""
2118        return f"*{except_}{replace}"
2119
2120    def parameter_sql(self, expression: exp.Parameter) -> str:
2121        this = self.sql(expression, "this")
2122        return f"{self.PARAMETER_TOKEN}{this}"
2123
2124    def sessionparameter_sql(self, expression: exp.SessionParameter) -> str:
2125        this = self.sql(expression, "this")
2126        kind = expression.text("kind")
2127        if kind:
2128            kind = f"{kind}."
2129        return f"@@{kind}{this}"
2130
2131    def placeholder_sql(self, expression: exp.Placeholder) -> str:
2132        return f":{expression.name}" if expression.name else "?"
2133
2134    def subquery_sql(self, expression: exp.Subquery, sep: str = " AS ") -> str:
2135        alias = self.sql(expression, "alias")
2136        alias = f"{sep}{alias}" if alias else ""
2137
2138        pivots = self.expressions(expression, key="pivots", sep=" ", flat=True)
2139        pivots = f" {pivots}" if pivots else ""
2140
2141        sql = self.query_modifiers(expression, self.wrap(expression), alias, pivots)
2142        return self.prepend_ctes(expression, sql)
2143
2144    def qualify_sql(self, expression: exp.Qualify) -> str:
2145        this = self.indent(self.sql(expression, "this"))
2146        return f"{self.seg('QUALIFY')}{self.sep()}{this}"
2147
2148    def union_sql(self, expression: exp.Union) -> str:
2149        return self.prepend_ctes(
2150            expression,
2151            self.set_operation(expression, self.union_op(expression)),
2152        )
2153
2154    def union_op(self, expression: exp.Union) -> str:
2155        kind = " DISTINCT" if self.EXPLICIT_UNION else ""
2156        kind = kind if expression.args.get("distinct") else " ALL"
2157        by_name = " BY NAME" if expression.args.get("by_name") else ""
2158        return f"UNION{kind}{by_name}"
2159
2160    def unnest_sql(self, expression: exp.Unnest) -> str:
2161        args = self.expressions(expression, flat=True)
2162
2163        alias = expression.args.get("alias")
2164        offset = expression.args.get("offset")
2165
2166        if self.UNNEST_WITH_ORDINALITY:
2167            if alias and isinstance(offset, exp.Expression):
2168                alias.append("columns", offset)
2169
2170        if alias and self.dialect.UNNEST_COLUMN_ONLY:
2171            columns = alias.columns
2172            alias = self.sql(columns[0]) if columns else ""
2173        else:
2174            alias = self.sql(alias)
2175
2176        alias = f" AS {alias}" if alias else alias
2177        if self.UNNEST_WITH_ORDINALITY:
2178            suffix = f" WITH ORDINALITY{alias}" if offset else alias
2179        else:
2180            if isinstance(offset, exp.Expression):
2181                suffix = f"{alias} WITH OFFSET AS {self.sql(offset)}"
2182            elif offset:
2183                suffix = f"{alias} WITH OFFSET"
2184            else:
2185                suffix = alias
2186
2187        return f"UNNEST({args}){suffix}"
2188
2189    def where_sql(self, expression: exp.Where) -> str:
2190        this = self.indent(self.sql(expression, "this"))
2191        return f"{self.seg('WHERE')}{self.sep()}{this}"
2192
2193    def window_sql(self, expression: exp.Window) -> str:
2194        this = self.sql(expression, "this")
2195        partition = self.partition_by_sql(expression)
2196        order = expression.args.get("order")
2197        order = self.order_sql(order, flat=True) if order else ""
2198        spec = self.sql(expression, "spec")
2199        alias = self.sql(expression, "alias")
2200        over = self.sql(expression, "over") or "OVER"
2201
2202        this = f"{this} {'AS' if expression.arg_key == 'windows' else over}"
2203
2204        first = expression.args.get("first")
2205        if first is None:
2206            first = ""
2207        else:
2208            first = "FIRST" if first else "LAST"
2209
2210        if not partition and not order and not spec and alias:
2211            return f"{this} {alias}"
2212
2213        args = " ".join(arg for arg in (alias, first, partition, order, spec) if arg)
2214        return f"{this} ({args})"
2215
2216    def partition_by_sql(self, expression: exp.Window | exp.MatchRecognize) -> str:
2217        partition = self.expressions(expression, key="partition_by", flat=True)
2218        return f"PARTITION BY {partition}" if partition else ""
2219
2220    def windowspec_sql(self, expression: exp.WindowSpec) -> str:
2221        kind = self.sql(expression, "kind")
2222        start = csv(self.sql(expression, "start"), self.sql(expression, "start_side"), sep=" ")
2223        end = (
2224            csv(self.sql(expression, "end"), self.sql(expression, "end_side"), sep=" ")
2225            or "CURRENT ROW"
2226        )
2227        return f"{kind} BETWEEN {start} AND {end}"
2228
2229    def withingroup_sql(self, expression: exp.WithinGroup) -> str:
2230        this = self.sql(expression, "this")
2231        expression_sql = self.sql(expression, "expression")[1:]  # order has a leading space
2232        return f"{this} WITHIN GROUP ({expression_sql})"
2233
2234    def between_sql(self, expression: exp.Between) -> str:
2235        this = self.sql(expression, "this")
2236        low = self.sql(expression, "low")
2237        high = self.sql(expression, "high")
2238        return f"{this} BETWEEN {low} AND {high}"
2239
2240    def bracket_sql(self, expression: exp.Bracket) -> str:
2241        expressions = apply_index_offset(
2242            expression.this,
2243            expression.expressions,
2244            self.dialect.INDEX_OFFSET - expression.args.get("offset", 0),
2245        )
2246        expressions_sql = ", ".join(self.sql(e) for e in expressions)
2247        return f"{self.sql(expression, 'this')}[{expressions_sql}]"
2248
2249    def all_sql(self, expression: exp.All) -> str:
2250        return f"ALL {self.wrap(expression)}"
2251
2252    def any_sql(self, expression: exp.Any) -> str:
2253        this = self.sql(expression, "this")
2254        if isinstance(expression.this, exp.Subqueryable):
2255            this = self.wrap(this)
2256        return f"ANY {this}"
2257
2258    def exists_sql(self, expression: exp.Exists) -> str:
2259        return f"EXISTS{self.wrap(expression)}"
2260
2261    def case_sql(self, expression: exp.Case) -> str:
2262        this = self.sql(expression, "this")
2263        statements = [f"CASE {this}" if this else "CASE"]
2264
2265        for e in expression.args["ifs"]:
2266            statements.append(f"WHEN {self.sql(e, 'this')}")
2267            statements.append(f"THEN {self.sql(e, 'true')}")
2268
2269        default = self.sql(expression, "default")
2270
2271        if default:
2272            statements.append(f"ELSE {default}")
2273
2274        statements.append("END")
2275
2276        if self.pretty and self.text_width(statements) > self.max_text_width:
2277            return self.indent("\n".join(statements), skip_first=True, skip_last=True)
2278
2279        return " ".join(statements)
2280
2281    def constraint_sql(self, expression: exp.Constraint) -> str:
2282        this = self.sql(expression, "this")
2283        expressions = self.expressions(expression, flat=True)
2284        return f"CONSTRAINT {this} {expressions}"
2285
2286    def nextvaluefor_sql(self, expression: exp.NextValueFor) -> str:
2287        order = expression.args.get("order")
2288        order = f" OVER ({self.order_sql(order, flat=True)})" if order else ""
2289        return f"NEXT VALUE FOR {self.sql(expression, 'this')}{order}"
2290
2291    def extract_sql(self, expression: exp.Extract) -> str:
2292        this = self.sql(expression, "this") if self.EXTRACT_ALLOWS_QUOTES else expression.this.name
2293        expression_sql = self.sql(expression, "expression")
2294        return f"EXTRACT({this} FROM {expression_sql})"
2295
2296    def trim_sql(self, expression: exp.Trim) -> str:
2297        trim_type = self.sql(expression, "position")
2298
2299        if trim_type == "LEADING":
2300            return self.func("LTRIM", expression.this)
2301        elif trim_type == "TRAILING":
2302            return self.func("RTRIM", expression.this)
2303        else:
2304            return self.func("TRIM", expression.this, expression.expression)
2305
2306    def convert_concat_args(self, expression: exp.Concat | exp.ConcatWs) -> t.List[exp.Expression]:
2307        args = expression.expressions
2308        if isinstance(expression, exp.ConcatWs):
2309            args = args[1:]  # Skip the delimiter
2310
2311        if self.dialect.STRICT_STRING_CONCAT and expression.args.get("safe"):
2312            args = [exp.cast(e, "text") for e in args]
2313
2314        if not self.dialect.CONCAT_COALESCE and expression.args.get("coalesce"):
2315            args = [exp.func("coalesce", e, exp.Literal.string("")) for e in args]
2316
2317        return args
2318
2319    def concat_sql(self, expression: exp.Concat) -> str:
2320        expressions = self.convert_concat_args(expression)
2321
2322        # Some dialects don't allow a single-argument CONCAT call
2323        if not self.SUPPORTS_SINGLE_ARG_CONCAT and len(expressions) == 1:
2324            return self.sql(expressions[0])
2325
2326        return self.func("CONCAT", *expressions)
2327
2328    def concatws_sql(self, expression: exp.ConcatWs) -> str:
2329        return self.func(
2330            "CONCAT_WS", seq_get(expression.expressions, 0), *self.convert_concat_args(expression)
2331        )
2332
2333    def check_sql(self, expression: exp.Check) -> str:
2334        this = self.sql(expression, key="this")
2335        return f"CHECK ({this})"
2336
2337    def foreignkey_sql(self, expression: exp.ForeignKey) -> str:
2338        expressions = self.expressions(expression, flat=True)
2339        reference = self.sql(expression, "reference")
2340        reference = f" {reference}" if reference else ""
2341        delete = self.sql(expression, "delete")
2342        delete = f" ON DELETE {delete}" if delete else ""
2343        update = self.sql(expression, "update")
2344        update = f" ON UPDATE {update}" if update else ""
2345        return f"FOREIGN KEY ({expressions}){reference}{delete}{update}"
2346
2347    def primarykey_sql(self, expression: exp.ForeignKey) -> str:
2348        expressions = self.expressions(expression, flat=True)
2349        options = self.expressions(expression, key="options", flat=True, sep=" ")
2350        options = f" {options}" if options else ""
2351        return f"PRIMARY KEY ({expressions}){options}"
2352
2353    def if_sql(self, expression: exp.If) -> str:
2354        return self.case_sql(exp.Case(ifs=[expression], default=expression.args.get("false")))
2355
2356    def matchagainst_sql(self, expression: exp.MatchAgainst) -> str:
2357        modifier = expression.args.get("modifier")
2358        modifier = f" {modifier}" if modifier else ""
2359        return f"{self.func('MATCH', *expression.expressions)} AGAINST({self.sql(expression, 'this')}{modifier})"
2360
2361    def jsonkeyvalue_sql(self, expression: exp.JSONKeyValue) -> str:
2362        return f"{self.sql(expression, 'this')}{self.JSON_KEY_VALUE_PAIR_SEP} {self.sql(expression, 'expression')}"
2363
2364    def formatjson_sql(self, expression: exp.FormatJson) -> str:
2365        return f"{self.sql(expression, 'this')} FORMAT JSON"
2366
2367    def jsonobject_sql(self, expression: exp.JSONObject | exp.JSONObjectAgg) -> str:
2368        null_handling = expression.args.get("null_handling")
2369        null_handling = f" {null_handling}" if null_handling else ""
2370
2371        unique_keys = expression.args.get("unique_keys")
2372        if unique_keys is not None:
2373            unique_keys = f" {'WITH' if unique_keys else 'WITHOUT'} UNIQUE KEYS"
2374        else:
2375            unique_keys = ""
2376
2377        return_type = self.sql(expression, "return_type")
2378        return_type = f" RETURNING {return_type}" if return_type else ""
2379        encoding = self.sql(expression, "encoding")
2380        encoding = f" ENCODING {encoding}" if encoding else ""
2381
2382        return self.func(
2383            "JSON_OBJECT" if isinstance(expression, exp.JSONObject) else "JSON_OBJECTAGG",
2384            *expression.expressions,
2385            suffix=f"{null_handling}{unique_keys}{return_type}{encoding})",
2386        )
2387
2388    def jsonobjectagg_sql(self, expression: exp.JSONObjectAgg) -> str:
2389        return self.jsonobject_sql(expression)
2390
2391    def jsonarray_sql(self, expression: exp.JSONArray) -> str:
2392        null_handling = expression.args.get("null_handling")
2393        null_handling = f" {null_handling}" if null_handling else ""
2394        return_type = self.sql(expression, "return_type")
2395        return_type = f" RETURNING {return_type}" if return_type else ""
2396        strict = " STRICT" if expression.args.get("strict") else ""
2397        return self.func(
2398            "JSON_ARRAY", *expression.expressions, suffix=f"{null_handling}{return_type}{strict})"
2399        )
2400
2401    def jsonarrayagg_sql(self, expression: exp.JSONArrayAgg) -> str:
2402        this = self.sql(expression, "this")
2403        order = self.sql(expression, "order")
2404        null_handling = expression.args.get("null_handling")
2405        null_handling = f" {null_handling}" if null_handling else ""
2406        return_type = self.sql(expression, "return_type")
2407        return_type = f" RETURNING {return_type}" if return_type else ""
2408        strict = " STRICT" if expression.args.get("strict") else ""
2409        return self.func(
2410            "JSON_ARRAYAGG",
2411            this,
2412            suffix=f"{order}{null_handling}{return_type}{strict})",
2413        )
2414
2415    def jsoncolumndef_sql(self, expression: exp.JSONColumnDef) -> str:
2416        path = self.sql(expression, "path")
2417        path = f" PATH {path}" if path else ""
2418        nested_schema = self.sql(expression, "nested_schema")
2419
2420        if nested_schema:
2421            return f"NESTED{path} {nested_schema}"
2422
2423        this = self.sql(expression, "this")
2424        kind = self.sql(expression, "kind")
2425        kind = f" {kind}" if kind else ""
2426        return f"{this}{kind}{path}"
2427
2428    def jsonschema_sql(self, expression: exp.JSONSchema) -> str:
2429        return self.func("COLUMNS", *expression.expressions)
2430
2431    def jsontable_sql(self, expression: exp.JSONTable) -> str:
2432        this = self.sql(expression, "this")
2433        path = self.sql(expression, "path")
2434        path = f", {path}" if path else ""
2435        error_handling = expression.args.get("error_handling")
2436        error_handling = f" {error_handling}" if error_handling else ""
2437        empty_handling = expression.args.get("empty_handling")
2438        empty_handling = f" {empty_handling}" if empty_handling else ""
2439        schema = self.sql(expression, "schema")
2440        return self.func(
2441            "JSON_TABLE", this, suffix=f"{path}{error_handling}{empty_handling} {schema})"
2442        )
2443
2444    def openjsoncolumndef_sql(self, expression: exp.OpenJSONColumnDef) -> str:
2445        this = self.sql(expression, "this")
2446        kind = self.sql(expression, "kind")
2447        path = self.sql(expression, "path")
2448        path = f" {path}" if path else ""
2449        as_json = " AS JSON" if expression.args.get("as_json") else ""
2450        return f"{this} {kind}{path}{as_json}"
2451
2452    def openjson_sql(self, expression: exp.OpenJSON) -> str:
2453        this = self.sql(expression, "this")
2454        path = self.sql(expression, "path")
2455        path = f", {path}" if path else ""
2456        expressions = self.expressions(expression)
2457        with_ = (
2458            f" WITH ({self.seg(self.indent(expressions), sep='')}{self.seg(')', sep='')}"
2459            if expressions
2460            else ""
2461        )
2462        return f"OPENJSON({this}{path}){with_}"
2463
2464    def in_sql(self, expression: exp.In) -> str:
2465        query = expression.args.get("query")
2466        unnest = expression.args.get("unnest")
2467        field = expression.args.get("field")
2468        is_global = " GLOBAL" if expression.args.get("is_global") else ""
2469
2470        if query:
2471            in_sql = self.wrap(query)
2472        elif unnest:
2473            in_sql = self.in_unnest_op(unnest)
2474        elif field:
2475            in_sql = self.sql(field)
2476        else:
2477            in_sql = f"({self.expressions(expression, flat=True)})"
2478
2479        return f"{self.sql(expression, 'this')}{is_global} IN {in_sql}"
2480
2481    def in_unnest_op(self, unnest: exp.Unnest) -> str:
2482        return f"(SELECT {self.sql(unnest)})"
2483
2484    def interval_sql(self, expression: exp.Interval) -> str:
2485        unit = self.sql(expression, "unit")
2486        if not self.INTERVAL_ALLOWS_PLURAL_FORM:
2487            unit = self.TIME_PART_SINGULARS.get(unit, unit)
2488        unit = f" {unit}" if unit else ""
2489
2490        if self.SINGLE_STRING_INTERVAL:
2491            this = expression.this.name if expression.this else ""
2492            return f"INTERVAL '{this}{unit}'" if this else f"INTERVAL{unit}"
2493
2494        this = self.sql(expression, "this")
2495        if this:
2496            unwrapped = isinstance(expression.this, self.UNWRAPPED_INTERVAL_VALUES)
2497            this = f" {this}" if unwrapped else f" ({this})"
2498
2499        return f"INTERVAL{this}{unit}"
2500
2501    def return_sql(self, expression: exp.Return) -> str:
2502        return f"RETURN {self.sql(expression, 'this')}"
2503
2504    def reference_sql(self, expression: exp.Reference) -> str:
2505        this = self.sql(expression, "this")
2506        expressions = self.expressions(expression, flat=True)
2507        expressions = f"({expressions})" if expressions else ""
2508        options = self.expressions(expression, key="options", flat=True, sep=" ")
2509        options = f" {options}" if options else ""
2510        return f"REFERENCES {this}{expressions}{options}"
2511
2512    def anonymous_sql(self, expression: exp.Anonymous) -> str:
2513        return self.func(expression.name, *expression.expressions)
2514
2515    def paren_sql(self, expression: exp.Paren) -> str:
2516        if isinstance(expression.unnest(), exp.Select):
2517            sql = self.wrap(expression)
2518        else:
2519            sql = self.seg(self.indent(self.sql(expression, "this")), sep="")
2520            sql = f"({sql}{self.seg(')', sep='')}"
2521
2522        return self.prepend_ctes(expression, sql)
2523
2524    def neg_sql(self, expression: exp.Neg) -> str:
2525        # This makes sure we don't convert "- - 5" to "--5", which is a comment
2526        this_sql = self.sql(expression, "this")
2527        sep = " " if this_sql[0] == "-" else ""
2528        return f"-{sep}{this_sql}"
2529
2530    def not_sql(self, expression: exp.Not) -> str:
2531        return f"NOT {self.sql(expression, 'this')}"
2532
2533    def alias_sql(self, expression: exp.Alias) -> str:
2534        alias = self.sql(expression, "alias")
2535        alias = f" AS {alias}" if alias else ""
2536        return f"{self.sql(expression, 'this')}{alias}"
2537
2538    def pivotalias_sql(self, expression: exp.PivotAlias) -> str:
2539        alias = expression.args["alias"]
2540        identifier_alias = isinstance(alias, exp.Identifier)
2541
2542        if identifier_alias and not self.UNPIVOT_ALIASES_ARE_IDENTIFIERS:
2543            alias.replace(exp.Literal.string(alias.output_name))
2544        elif not identifier_alias and self.UNPIVOT_ALIASES_ARE_IDENTIFIERS:
2545            alias.replace(exp.to_identifier(alias.output_name))
2546
2547        return self.alias_sql(expression)
2548
2549    def aliases_sql(self, expression: exp.Aliases) -> str:
2550        return f"{self.sql(expression, 'this')} AS ({self.expressions(expression, flat=True)})"
2551
2552    def atindex_sql(self, expression: exp.AtTimeZone) -> str:
2553        this = self.sql(expression, "this")
2554        index = self.sql(expression, "expression")
2555        return f"{this} AT {index}"
2556
2557    def attimezone_sql(self, expression: exp.AtTimeZone) -> str:
2558        this = self.sql(expression, "this")
2559        zone = self.sql(expression, "zone")
2560        return f"{this} AT TIME ZONE {zone}"
2561
2562    def fromtimezone_sql(self, expression: exp.FromTimeZone) -> str:
2563        this = self.sql(expression, "this")
2564        zone = self.sql(expression, "zone")
2565        return f"{this} AT TIME ZONE {zone} AT TIME ZONE 'UTC'"
2566
2567    def add_sql(self, expression: exp.Add) -> str:
2568        return self.binary(expression, "+")
2569
2570    def and_sql(self, expression: exp.And) -> str:
2571        return self.connector_sql(expression, "AND")
2572
2573    def xor_sql(self, expression: exp.Xor) -> str:
2574        return self.connector_sql(expression, "XOR")
2575
2576    def connector_sql(self, expression: exp.Connector, op: str) -> str:
2577        if not self.pretty:
2578            return self.binary(expression, op)
2579
2580        sqls = tuple(
2581            self.maybe_comment(self.sql(e), e, e.parent.comments or []) if i != 1 else self.sql(e)
2582            for i, e in enumerate(expression.flatten(unnest=False))
2583        )
2584
2585        sep = "\n" if self.text_width(sqls) > self.max_text_width else " "
2586        return f"{sep}{op} ".join(sqls)
2587
2588    def bitwiseand_sql(self, expression: exp.BitwiseAnd) -> str:
2589        return self.binary(expression, "&")
2590
2591    def bitwiseleftshift_sql(self, expression: exp.BitwiseLeftShift) -> str:
2592        return self.binary(expression, "<<")
2593
2594    def bitwisenot_sql(self, expression: exp.BitwiseNot) -> str:
2595        return f"~{self.sql(expression, 'this')}"
2596
2597    def bitwiseor_sql(self, expression: exp.BitwiseOr) -> str:
2598        return self.binary(expression, "|")
2599
2600    def bitwiserightshift_sql(self, expression: exp.BitwiseRightShift) -> str:
2601        return self.binary(expression, ">>")
2602
2603    def bitwisexor_sql(self, expression: exp.BitwiseXor) -> str:
2604        return self.binary(expression, "^")
2605
2606    def cast_sql(self, expression: exp.Cast, safe_prefix: t.Optional[str] = None) -> str:
2607        format_sql = self.sql(expression, "format")
2608        format_sql = f" FORMAT {format_sql}" if format_sql else ""
2609        to_sql = self.sql(expression, "to")
2610        to_sql = f" {to_sql}" if to_sql else ""
2611        return f"{safe_prefix or ''}CAST({self.sql(expression, 'this')} AS{to_sql}{format_sql})"
2612
2613    def currentdate_sql(self, expression: exp.CurrentDate) -> str:
2614        zone = self.sql(expression, "this")
2615        return f"CURRENT_DATE({zone})" if zone else "CURRENT_DATE"
2616
2617    def collate_sql(self, expression: exp.Collate) -> str:
2618        if self.COLLATE_IS_FUNC:
2619            return self.function_fallback_sql(expression)
2620        return self.binary(expression, "COLLATE")
2621
2622    def command_sql(self, expression: exp.Command) -> str:
2623        return f"{self.sql(expression, 'this')} {expression.text('expression').strip()}"
2624
2625    def comment_sql(self, expression: exp.Comment) -> str:
2626        this = self.sql(expression, "this")
2627        kind = expression.args["kind"]
2628        exists_sql = " IF EXISTS " if expression.args.get("exists") else " "
2629        expression_sql = self.sql(expression, "expression")
2630        return f"COMMENT{exists_sql}ON {kind} {this} IS {expression_sql}"
2631
2632    def mergetreettlaction_sql(self, expression: exp.MergeTreeTTLAction) -> str:
2633        this = self.sql(expression, "this")
2634        delete = " DELETE" if expression.args.get("delete") else ""
2635        recompress = self.sql(expression, "recompress")
2636        recompress = f" RECOMPRESS {recompress}" if recompress else ""
2637        to_disk = self.sql(expression, "to_disk")
2638        to_disk = f" TO DISK {to_disk}" if to_disk else ""
2639        to_volume = self.sql(expression, "to_volume")
2640        to_volume = f" TO VOLUME {to_volume}" if to_volume else ""
2641        return f"{this}{delete}{recompress}{to_disk}{to_volume}"
2642
2643    def mergetreettl_sql(self, expression: exp.MergeTreeTTL) -> str:
2644        where = self.sql(expression, "where")
2645        group = self.sql(expression, "group")
2646        aggregates = self.expressions(expression, key="aggregates")
2647        aggregates = self.seg("SET") + self.seg(aggregates) if aggregates else ""
2648
2649        if not (where or group or aggregates) and len(expression.expressions) == 1:
2650            return f"TTL {self.expressions(expression, flat=True)}"
2651
2652        return f"TTL{self.seg(self.expressions(expression))}{where}{group}{aggregates}"
2653
2654    def transaction_sql(self, expression: exp.Transaction) -> str:
2655        return "BEGIN"
2656
2657    def commit_sql(self, expression: exp.Commit) -> str:
2658        chain = expression.args.get("chain")
2659        if chain is not None:
2660            chain = " AND CHAIN" if chain else " AND NO CHAIN"
2661
2662        return f"COMMIT{chain or ''}"
2663
2664    def rollback_sql(self, expression: exp.Rollback) -> str:
2665        savepoint = expression.args.get("savepoint")
2666        savepoint = f" TO {savepoint}" if savepoint else ""
2667        return f"ROLLBACK{savepoint}"
2668
2669    def altercolumn_sql(self, expression: exp.AlterColumn) -> str:
2670        this = self.sql(expression, "this")
2671
2672        dtype = self.sql(expression, "dtype")
2673        if dtype:
2674            collate = self.sql(expression, "collate")
2675            collate = f" COLLATE {collate}" if collate else ""
2676            using = self.sql(expression, "using")
2677            using = f" USING {using}" if using else ""
2678            return f"ALTER COLUMN {this} SET DATA TYPE {dtype}{collate}{using}"
2679
2680        default = self.sql(expression, "default")
2681        if default:
2682            return f"ALTER COLUMN {this} SET DEFAULT {default}"
2683
2684        if not expression.args.get("drop"):
2685            self.unsupported("Unsupported ALTER COLUMN syntax")
2686
2687        return f"ALTER COLUMN {this} DROP DEFAULT"
2688
2689    def renametable_sql(self, expression: exp.RenameTable) -> str:
2690        if not self.RENAME_TABLE_WITH_DB:
2691            # Remove db from tables
2692            expression = expression.transform(
2693                lambda n: exp.table_(n.this) if isinstance(n, exp.Table) else n
2694            )
2695        this = self.sql(expression, "this")
2696        return f"RENAME TO {this}"
2697
2698    def renamecolumn_sql(self, expression: exp.RenameColumn) -> str:
2699        exists = " IF EXISTS" if expression.args.get("exists") else ""
2700        old_column = self.sql(expression, "this")
2701        new_column = self.sql(expression, "to")
2702        return f"RENAME COLUMN{exists} {old_column} TO {new_column}"
2703
2704    def altertable_sql(self, expression: exp.AlterTable) -> str:
2705        actions = expression.args["actions"]
2706
2707        if isinstance(actions[0], exp.ColumnDef):
2708            actions = self.add_column_sql(expression)
2709        elif isinstance(actions[0], exp.Schema):
2710            actions = self.expressions(expression, key="actions", prefix="ADD COLUMNS ")
2711        elif isinstance(actions[0], exp.Delete):
2712            actions = self.expressions(expression, key="actions", flat=True)
2713        else:
2714            actions = self.expressions(expression, key="actions", flat=True)
2715
2716        exists = " IF EXISTS" if expression.args.get("exists") else ""
2717        only = " ONLY" if expression.args.get("only") else ""
2718        return f"ALTER TABLE{exists}{only} {self.sql(expression, 'this')} {actions}"
2719
2720    def add_column_sql(self, expression: exp.AlterTable) -> str:
2721        if self.ALTER_TABLE_INCLUDE_COLUMN_KEYWORD:
2722            return self.expressions(
2723                expression,
2724                key="actions",
2725                prefix="ADD COLUMN ",
2726            )
2727        return f"ADD {self.expressions(expression, key='actions', flat=True)}"
2728
2729    def droppartition_sql(self, expression: exp.DropPartition) -> str:
2730        expressions = self.expressions(expression)
2731        exists = " IF EXISTS " if expression.args.get("exists") else " "
2732        return f"DROP{exists}{expressions}"
2733
2734    def addconstraint_sql(self, expression: exp.AddConstraint) -> str:
2735        this = self.sql(expression, "this")
2736        expression_ = self.sql(expression, "expression")
2737        add_constraint = f"ADD CONSTRAINT {this}" if this else "ADD"
2738
2739        enforced = expression.args.get("enforced")
2740        if enforced is not None:
2741            return f"{add_constraint} CHECK ({expression_}){' ENFORCED' if enforced else ''}"
2742
2743        return f"{add_constraint} {expression_}"
2744
2745    def distinct_sql(self, expression: exp.Distinct) -> str:
2746        this = self.expressions(expression, flat=True)
2747        this = f" {this}" if this else ""
2748
2749        on = self.sql(expression, "on")
2750        on = f" ON {on}" if on else ""
2751        return f"DISTINCT{this}{on}"
2752
2753    def ignorenulls_sql(self, expression: exp.IgnoreNulls) -> str:
2754        return f"{self.sql(expression, 'this')} IGNORE NULLS"
2755
2756    def respectnulls_sql(self, expression: exp.RespectNulls) -> str:
2757        return f"{self.sql(expression, 'this')} RESPECT NULLS"
2758
2759    def intdiv_sql(self, expression: exp.IntDiv) -> str:
2760        return self.sql(
2761            exp.Cast(
2762                this=exp.Div(this=expression.this, expression=expression.expression),
2763                to=exp.DataType(this=exp.DataType.Type.INT),
2764            )
2765        )
2766
2767    def dpipe_sql(self, expression: exp.DPipe) -> str:
2768        if self.dialect.STRICT_STRING_CONCAT and expression.args.get("safe"):
2769            return self.func("CONCAT", *(exp.cast(e, "text") for e in expression.flatten()))
2770        return self.binary(expression, "||")
2771
2772    def div_sql(self, expression: exp.Div) -> str:
2773        l, r = expression.left, expression.right
2774
2775        if not self.dialect.SAFE_DIVISION and expression.args.get("safe"):
2776            r.replace(exp.Nullif(this=r.copy(), expression=exp.Literal.number(0)))
2777
2778        if self.dialect.TYPED_DIVISION and not expression.args.get("typed"):
2779            if not l.is_type(*exp.DataType.FLOAT_TYPES) and not r.is_type(
2780                *exp.DataType.FLOAT_TYPES
2781            ):
2782                l.replace(exp.cast(l.copy(), to=exp.DataType.Type.DOUBLE))
2783
2784        elif not self.dialect.TYPED_DIVISION and expression.args.get("typed"):
2785            if l.is_type(*exp.DataType.INTEGER_TYPES) and r.is_type(*exp.DataType.INTEGER_TYPES):
2786                return self.sql(
2787                    exp.cast(
2788                        l / r,
2789                        to=exp.DataType.Type.BIGINT,
2790                    )
2791                )
2792
2793        return self.binary(expression, "/")
2794
2795    def overlaps_sql(self, expression: exp.Overlaps) -> str:
2796        return self.binary(expression, "OVERLAPS")
2797
2798    def distance_sql(self, expression: exp.Distance) -> str:
2799        return self.binary(expression, "<->")
2800
2801    def dot_sql(self, expression: exp.Dot) -> str:
2802        return f"{self.sql(expression, 'this')}.{self.sql(expression, 'expression')}"
2803
2804    def eq_sql(self, expression: exp.EQ) -> str:
2805        return self.binary(expression, "=")
2806
2807    def propertyeq_sql(self, expression: exp.PropertyEQ) -> str:
2808        return self.binary(expression, ":=")
2809
2810    def escape_sql(self, expression: exp.Escape) -> str:
2811        return self.binary(expression, "ESCAPE")
2812
2813    def glob_sql(self, expression: exp.Glob) -> str:
2814        return self.binary(expression, "GLOB")
2815
2816    def gt_sql(self, expression: exp.GT) -> str:
2817        return self.binary(expression, ">")
2818
2819    def gte_sql(self, expression: exp.GTE) -> str:
2820        return self.binary(expression, ">=")
2821
2822    def ilike_sql(self, expression: exp.ILike) -> str:
2823        return self.binary(expression, "ILIKE")
2824
2825    def ilikeany_sql(self, expression: exp.ILikeAny) -> str:
2826        return self.binary(expression, "ILIKE ANY")
2827
2828    def is_sql(self, expression: exp.Is) -> str:
2829        if not self.IS_BOOL_ALLOWED and isinstance(expression.expression, exp.Boolean):
2830            return self.sql(
2831                expression.this if expression.expression.this else exp.not_(expression.this)
2832            )
2833        return self.binary(expression, "IS")
2834
2835    def like_sql(self, expression: exp.Like) -> str:
2836        return self.binary(expression, "LIKE")
2837
2838    def likeany_sql(self, expression: exp.LikeAny) -> str:
2839        return self.binary(expression, "LIKE ANY")
2840
2841    def similarto_sql(self, expression: exp.SimilarTo) -> str:
2842        return self.binary(expression, "SIMILAR TO")
2843
2844    def lt_sql(self, expression: exp.LT) -> str:
2845        return self.binary(expression, "<")
2846
2847    def lte_sql(self, expression: exp.LTE) -> str:
2848        return self.binary(expression, "<=")
2849
2850    def mod_sql(self, expression: exp.Mod) -> str:
2851        return self.binary(expression, "%")
2852
2853    def mul_sql(self, expression: exp.Mul) -> str:
2854        return self.binary(expression, "*")
2855
2856    def neq_sql(self, expression: exp.NEQ) -> str:
2857        return self.binary(expression, "<>")
2858
2859    def nullsafeeq_sql(self, expression: exp.NullSafeEQ) -> str:
2860        return self.binary(expression, "IS NOT DISTINCT FROM")
2861
2862    def nullsafeneq_sql(self, expression: exp.NullSafeNEQ) -> str:
2863        return self.binary(expression, "IS DISTINCT FROM")
2864
2865    def or_sql(self, expression: exp.Or) -> str:
2866        return self.connector_sql(expression, "OR")
2867
2868    def slice_sql(self, expression: exp.Slice) -> str:
2869        return self.binary(expression, ":")
2870
2871    def sub_sql(self, expression: exp.Sub) -> str:
2872        return self.binary(expression, "-")
2873
2874    def trycast_sql(self, expression: exp.TryCast) -> str:
2875        return self.cast_sql(expression, safe_prefix="TRY_")
2876
2877    def log_sql(self, expression: exp.Log) -> str:
2878        this = expression.this
2879        expr = expression.expression
2880
2881        if not self.dialect.LOG_BASE_FIRST:
2882            this, expr = expr, this
2883
2884        return self.func("LOG", this, expr)
2885
2886    def use_sql(self, expression: exp.Use) -> str:
2887        kind = self.sql(expression, "kind")
2888        kind = f" {kind}" if kind else ""
2889        this = self.sql(expression, "this")
2890        this = f" {this}" if this else ""
2891        return f"USE{kind}{this}"
2892
2893    def binary(self, expression: exp.Binary, op: str) -> str:
2894        op = self.maybe_comment(op, comments=expression.comments)
2895        return f"{self.sql(expression, 'this')} {op} {self.sql(expression, 'expression')}"
2896
2897    def function_fallback_sql(self, expression: exp.Func) -> str:
2898        args = []
2899
2900        for key in expression.arg_types:
2901            arg_value = expression.args.get(key)
2902
2903            if isinstance(arg_value, list):
2904                for value in arg_value:
2905                    args.append(value)
2906            elif arg_value is not None:
2907                args.append(arg_value)
2908
2909        if self.normalize_functions:
2910            name = expression.sql_name()
2911        else:
2912            name = (expression._meta and expression.meta.get("name")) or expression.sql_name()
2913
2914        return self.func(name, *args)
2915
2916    def func(
2917        self,
2918        name: str,
2919        *args: t.Optional[exp.Expression | str],
2920        prefix: str = "(",
2921        suffix: str = ")",
2922    ) -> str:
2923        return f"{self.normalize_func(name)}{prefix}{self.format_args(*args)}{suffix}"
2924
2925    def format_args(self, *args: t.Optional[str | exp.Expression]) -> str:
2926        arg_sqls = tuple(self.sql(arg) for arg in args if arg is not None)
2927        if self.pretty and self.text_width(arg_sqls) > self.max_text_width:
2928            return self.indent("\n" + f",\n".join(arg_sqls) + "\n", skip_first=True, skip_last=True)
2929        return ", ".join(arg_sqls)
2930
2931    def text_width(self, args: t.Iterable) -> int:
2932        return sum(len(arg) for arg in args)
2933
2934    def format_time(self, expression: exp.Expression) -> t.Optional[str]:
2935        return format_time(
2936            self.sql(expression, "format"),
2937            self.dialect.INVERSE_TIME_MAPPING,
2938            self.dialect.INVERSE_TIME_TRIE,
2939        )
2940
2941    def expressions(
2942        self,
2943        expression: t.Optional[exp.Expression] = None,
2944        key: t.Optional[str] = None,
2945        sqls: t.Optional[t.Collection[str | exp.Expression]] = None,
2946        flat: bool = False,
2947        indent: bool = True,
2948        skip_first: bool = False,
2949        sep: str = ", ",
2950        prefix: str = "",
2951    ) -> str:
2952        expressions = expression.args.get(key or "expressions") if expression else sqls
2953
2954        if not expressions:
2955            return ""
2956
2957        if flat:
2958            return sep.join(sql for sql in (self.sql(e) for e in expressions) if sql)
2959
2960        num_sqls = len(expressions)
2961
2962        # These are calculated once in case we have the leading_comma / pretty option set, correspondingly
2963        pad = " " * self.pad
2964        stripped_sep = sep.strip()
2965
2966        result_sqls = []
2967        for i, e in enumerate(expressions):
2968            sql = self.sql(e, comment=False)
2969            if not sql:
2970                continue
2971
2972            comments = self.maybe_comment("", e) if isinstance(e, exp.Expression) else ""
2973
2974            if self.pretty:
2975                if self.leading_comma:
2976                    result_sqls.append(f"{sep if i > 0 else pad}{prefix}{sql}{comments}")
2977                else:
2978                    result_sqls.append(
2979                        f"{prefix}{sql}{stripped_sep if i + 1 < num_sqls else ''}{comments}"
2980                    )
2981            else:
2982                result_sqls.append(f"{prefix}{sql}{comments}{sep if i + 1 < num_sqls else ''}")
2983
2984        result_sql = "\n".join(result_sqls) if self.pretty else "".join(result_sqls)
2985        return self.indent(result_sql, skip_first=skip_first) if indent else result_sql
2986
2987    def op_expressions(self, op: str, expression: exp.Expression, flat: bool = False) -> str:
2988        flat = flat or isinstance(expression.parent, exp.Properties)
2989        expressions_sql = self.expressions(expression, flat=flat)
2990        if flat:
2991            return f"{op} {expressions_sql}"
2992        return f"{self.seg(op)}{self.sep() if expressions_sql else ''}{expressions_sql}"
2993
2994    def naked_property(self, expression: exp.Property) -> str:
2995        property_name = exp.Properties.PROPERTY_TO_NAME.get(expression.__class__)
2996        if not property_name:
2997            self.unsupported(f"Unsupported property {expression.__class__.__name__}")
2998        return f"{property_name} {self.sql(expression, 'this')}"
2999
3000    def set_operation(self, expression: exp.Union, op: str) -> str:
3001        this = self.maybe_comment(self.sql(expression, "this"), comments=expression.comments)
3002        op = self.seg(op)
3003        return self.query_modifiers(
3004            expression, f"{this}{op}{self.sep()}{self.sql(expression, 'expression')}"
3005        )
3006
3007    def tag_sql(self, expression: exp.Tag) -> str:
3008        return f"{expression.args.get('prefix')}{self.sql(expression.this)}{expression.args.get('postfix')}"
3009
3010    def token_sql(self, token_type: TokenType) -> str:
3011        return self.TOKEN_MAPPING.get(token_type, token_type.name)
3012
3013    def userdefinedfunction_sql(self, expression: exp.UserDefinedFunction) -> str:
3014        this = self.sql(expression, "this")
3015        expressions = self.no_identify(self.expressions, expression)
3016        expressions = (
3017            self.wrap(expressions) if expression.args.get("wrapped") else f" {expressions}"
3018        )
3019        return f"{this}{expressions}"
3020
3021    def joinhint_sql(self, expression: exp.JoinHint) -> str:
3022        this = self.sql(expression, "this")
3023        expressions = self.expressions(expression, flat=True)
3024        return f"{this}({expressions})"
3025
3026    def kwarg_sql(self, expression: exp.Kwarg) -> str:
3027        return self.binary(expression, "=>")
3028
3029    def when_sql(self, expression: exp.When) -> str:
3030        matched = "MATCHED" if expression.args["matched"] else "NOT MATCHED"
3031        source = " BY SOURCE" if self.MATCHED_BY_SOURCE and expression.args.get("source") else ""
3032        condition = self.sql(expression, "condition")
3033        condition = f" AND {condition}" if condition else ""
3034
3035        then_expression = expression.args.get("then")
3036        if isinstance(then_expression, exp.Insert):
3037            then = f"INSERT {self.sql(then_expression, 'this')}"
3038            if "expression" in then_expression.args:
3039                then += f" VALUES {self.sql(then_expression, 'expression')}"
3040        elif isinstance(then_expression, exp.Update):
3041            if isinstance(then_expression.args.get("expressions"), exp.Star):
3042                then = f"UPDATE {self.sql(then_expression, 'expressions')}"
3043            else:
3044                then = f"UPDATE SET {self.expressions(then_expression, flat=True)}"
3045        else:
3046            then = self.sql(then_expression)
3047        return f"WHEN {matched}{source}{condition} THEN {then}"
3048
3049    def merge_sql(self, expression: exp.Merge) -> str:
3050        table = expression.this
3051        table_alias = ""
3052
3053        hints = table.args.get("hints")
3054        if hints and table.alias and isinstance(hints[0], exp.WithTableHint):
3055            # T-SQL syntax is MERGE ... <target_table> [WITH (<merge_hint>)] [[AS] table_alias]
3056            table_alias = f" AS {self.sql(table.args['alias'].pop())}"
3057
3058        this = self.sql(table)
3059        using = f"USING {self.sql(expression, 'using')}"
3060        on = f"ON {self.sql(expression, 'on')}"
3061        expressions = self.expressions(expression, sep=" ")
3062
3063        return self.prepend_ctes(
3064            expression, f"MERGE INTO {this}{table_alias} {using} {on} {expressions}"
3065        )
3066
3067    def tochar_sql(self, expression: exp.ToChar) -> str:
3068        if expression.args.get("format"):
3069            self.unsupported("Format argument unsupported for TO_CHAR/TO_VARCHAR function")
3070
3071        return self.sql(exp.cast(expression.this, "text"))
3072
3073    def dictproperty_sql(self, expression: exp.DictProperty) -> str:
3074        this = self.sql(expression, "this")
3075        kind = self.sql(expression, "kind")
3076        settings_sql = self.expressions(expression, key="settings", sep=" ")
3077        args = f"({self.sep('')}{settings_sql}{self.seg(')', sep='')}" if settings_sql else "()"
3078        return f"{this}({kind}{args})"
3079
3080    def dictrange_sql(self, expression: exp.DictRange) -> str:
3081        this = self.sql(expression, "this")
3082        max = self.sql(expression, "max")
3083        min = self.sql(expression, "min")
3084        return f"{this}(MIN {min} MAX {max})"
3085
3086    def dictsubproperty_sql(self, expression: exp.DictSubProperty) -> str:
3087        return f"{self.sql(expression, 'this')} {self.sql(expression, 'value')}"
3088
3089    def oncluster_sql(self, expression: exp.OnCluster) -> str:
3090        return ""
3091
3092    def clusteredbyproperty_sql(self, expression: exp.ClusteredByProperty) -> str:
3093        expressions = self.expressions(expression, key="expressions", flat=True)
3094        sorted_by = self.expressions(expression, key="sorted_by", flat=True)
3095        sorted_by = f" SORTED BY ({sorted_by})" if sorted_by else ""
3096        buckets = self.sql(expression, "buckets")
3097        return f"CLUSTERED BY ({expressions}){sorted_by} INTO {buckets} BUCKETS"
3098
3099    def anyvalue_sql(self, expression: exp.AnyValue) -> str:
3100        this = self.sql(expression, "this")
3101        having = self.sql(expression, "having")
3102
3103        if having:
3104            this = f"{this} HAVING {'MAX' if expression.args.get('max') else 'MIN'} {having}"
3105
3106        return self.func("ANY_VALUE", this)
3107
3108    def querytransform_sql(self, expression: exp.QueryTransform) -> str:
3109        transform = self.func("TRANSFORM", *expression.expressions)
3110        row_format_before = self.sql(expression, "row_format_before")
3111        row_format_before = f" {row_format_before}" if row_format_before else ""
3112        record_writer = self.sql(expression, "record_writer")
3113        record_writer = f" RECORDWRITER {record_writer}" if record_writer else ""
3114        using = f" USING {self.sql(expression, 'command_script')}"
3115        schema = self.sql(expression, "schema")
3116        schema = f" AS {schema}" if schema else ""
3117        row_format_after = self.sql(expression, "row_format_after")
3118        row_format_after = f" {row_format_after}" if row_format_after else ""
3119        record_reader = self.sql(expression, "record_reader")
3120        record_reader = f" RECORDREADER {record_reader}" if record_reader else ""
3121        return f"{transform}{row_format_before}{record_writer}{using}{schema}{row_format_after}{record_reader}"
3122
3123    def indexconstraintoption_sql(self, expression: exp.IndexConstraintOption) -> str:
3124        key_block_size = self.sql(expression, "key_block_size")
3125        if key_block_size:
3126            return f"KEY_BLOCK_SIZE = {key_block_size}"
3127
3128        using = self.sql(expression, "using")
3129        if using:
3130            return f"USING {using}"
3131
3132        parser = self.sql(expression, "parser")
3133        if parser:
3134            return f"WITH PARSER {parser}"
3135
3136        comment = self.sql(expression, "comment")
3137        if comment:
3138            return f"COMMENT {comment}"
3139
3140        visible = expression.args.get("visible")
3141        if visible is not None:
3142            return "VISIBLE" if visible else "INVISIBLE"
3143
3144        engine_attr = self.sql(expression, "engine_attr")
3145        if engine_attr:
3146            return f"ENGINE_ATTRIBUTE = {engine_attr}"
3147
3148        secondary_engine_attr = self.sql(expression, "secondary_engine_attr")
3149        if secondary_engine_attr:
3150            return f"SECONDARY_ENGINE_ATTRIBUTE = {secondary_engine_attr}"
3151
3152        self.unsupported("Unsupported index constraint option.")
3153        return ""
3154
3155    def indexcolumnconstraint_sql(self, expression: exp.IndexColumnConstraint) -> str:
3156        kind = self.sql(expression, "kind")
3157        kind = f"{kind} INDEX" if kind else "INDEX"
3158        this = self.sql(expression, "this")
3159        this = f" {this}" if this else ""
3160        index_type = self.sql(expression, "index_type")
3161        index_type = f" USING {index_type}" if index_type else ""
3162        schema = self.sql(expression, "schema")
3163        schema = f" {schema}" if schema else ""
3164        options = self.expressions(expression, key="options", sep=" ")
3165        options = f" {options}" if options else ""
3166        return f"{kind}{this}{index_type}{schema}{options}"
3167
3168    def nvl2_sql(self, expression: exp.Nvl2) -> str:
3169        if self.NVL2_SUPPORTED:
3170            return self.function_fallback_sql(expression)
3171
3172        case = exp.Case().when(
3173            expression.this.is_(exp.null()).not_(copy=False),
3174            expression.args["true"],
3175            copy=False,
3176        )
3177        else_cond = expression.args.get("false")
3178        if else_cond:
3179            case.else_(else_cond, copy=False)
3180
3181        return self.sql(case)
3182
3183    def comprehension_sql(self, expression: exp.Comprehension) -> str:
3184        this = self.sql(expression, "this")
3185        expr = self.sql(expression, "expression")
3186        iterator = self.sql(expression, "iterator")
3187        condition = self.sql(expression, "condition")
3188        condition = f" IF {condition}" if condition else ""
3189        return f"{this} FOR {expr} IN {iterator}{condition}"
3190
3191    def columnprefix_sql(self, expression: exp.ColumnPrefix) -> str:
3192        return f"{self.sql(expression, 'this')}({self.sql(expression, 'expression')})"
3193
3194    def opclass_sql(self, expression: exp.Opclass) -> str:
3195        return f"{self.sql(expression, 'this')} {self.sql(expression, 'expression')}"
3196
3197    def predict_sql(self, expression: exp.Predict) -> str:
3198        model = self.sql(expression, "this")
3199        model = f"MODEL {model}"
3200        table = self.sql(expression, "expression")
3201        table = f"TABLE {table}" if not isinstance(expression.expression, exp.Subquery) else table
3202        parameters = self.sql(expression, "params_struct")
3203        return self.func("PREDICT", model, table, parameters or None)
3204
3205    def forin_sql(self, expression: exp.ForIn) -> str:
3206        this = self.sql(expression, "this")
3207        expression_sql = self.sql(expression, "expression")
3208        return f"FOR {this} DO {expression_sql}"
3209
3210    def refresh_sql(self, expression: exp.Refresh) -> str:
3211        this = self.sql(expression, "this")
3212        table = "" if isinstance(expression.this, exp.Literal) else "TABLE "
3213        return f"REFRESH {table}{this}"
3214
3215    def operator_sql(self, expression: exp.Operator) -> str:
3216        return self.binary(expression, f"OPERATOR({self.sql(expression, 'operator')})")
3217
3218    def toarray_sql(self, expression: exp.ToArray) -> str:
3219        arg = expression.this
3220        if not arg.type:
3221            from sqlglot.optimizer.annotate_types import annotate_types
3222
3223            arg = annotate_types(arg)
3224
3225        if arg.is_type(exp.DataType.Type.ARRAY):
3226            return self.sql(arg)
3227
3228        cond_for_null = arg.is_(exp.null())
3229        return self.sql(exp.func("IF", cond_for_null, exp.null(), exp.Array(expressions=[arg])))
3230
3231    def tsordstotime_sql(self, expression: exp.TsOrDsToTime) -> str:
3232        this = expression.this
3233        if isinstance(this, exp.TsOrDsToTime) or this.is_type(exp.DataType.Type.TIME):
3234            return self.sql(this)
3235
3236        return self.sql(exp.cast(this, "time"))
3237
3238    def tsordstodate_sql(self, expression: exp.TsOrDsToDate) -> str:
3239        this = expression.this
3240        time_format = self.format_time(expression)
3241
3242        if time_format and time_format not in (self.dialect.TIME_FORMAT, self.dialect.DATE_FORMAT):
3243            return self.sql(
3244                exp.cast(exp.StrToTime(this=this, format=expression.args["format"]), "date")
3245            )
3246
3247        if isinstance(this, exp.TsOrDsToDate) or this.is_type(exp.DataType.Type.DATE):
3248            return self.sql(this)
3249
3250        return self.sql(exp.cast(this, "date"))
3251
3252    def unixdate_sql(self, expression: exp.UnixDate) -> str:
3253        return self.sql(
3254            exp.func(
3255                "DATEDIFF",
3256                expression.this,
3257                exp.cast(exp.Literal.string("1970-01-01"), "date"),
3258                "day",
3259            )
3260        )
3261
3262    def lastday_sql(self, expression: exp.LastDay) -> str:
3263        if self.LAST_DAY_SUPPORTS_DATE_PART:
3264            return self.function_fallback_sql(expression)
3265
3266        unit = expression.text("unit")
3267        if unit and unit != "MONTH":
3268            self.unsupported("Date parts are not supported in LAST_DAY.")
3269
3270        return self.func("LAST_DAY", expression.this)
3271
3272    def _simplify_unless_literal(self, expression: E) -> E:
3273        if not isinstance(expression, exp.Literal):
3274            from sqlglot.optimizer.simplify import simplify
3275
3276            expression = simplify(expression, dialect=self.dialect)
3277
3278        return expression
3279
3280    def _ensure_string_if_null(self, values: t.List[exp.Expression]) -> t.List[exp.Expression]:
3281        return [
3282            exp.func("COALESCE", exp.cast(value, "text"), exp.Literal.string(""))
3283            for value in values
3284            if value
3285        ]