sqlglot.generator

   1from __future__ import annotations
   2
   3import logging
   4import typing as t
   5from collections import defaultdict
   6
   7from sqlglot import exp
   8from sqlglot.errors import ErrorLevel, UnsupportedError, concat_messages
   9from sqlglot.helper import apply_index_offset, csv, seq_get
  10from sqlglot.time import format_time
  11from sqlglot.tokens import TokenType
  12
  13logger = logging.getLogger("sqlglot")
  14
  15
  16class Generator:
  17    """
  18    Generator converts a given syntax tree to the corresponding SQL string.
  19
  20    Args:
  21        pretty: Whether or not to format the produced SQL string.
  22            Default: False.
  23        identify: Determines when an identifier should be quoted. Possible values are:
  24            False (default): Never quote, except in cases where it's mandatory by the dialect.
  25            True or 'always': Always quote.
  26            'safe': Only quote identifiers that are case insensitive.
  27        normalize: Whether or not to normalize identifiers to lowercase.
  28            Default: False.
  29        pad: Determines the pad size in a formatted string.
  30            Default: 2.
  31        indent: Determines the indentation size in a formatted string.
  32            Default: 2.
  33        normalize_functions: Whether or not to normalize all function names. Possible values are:
  34            "upper" or True (default): Convert names to uppercase.
  35            "lower": Convert names to lowercase.
  36            False: Disables function name normalization.
  37        unsupported_level: Determines the generator's behavior when it encounters unsupported expressions.
  38            Default ErrorLevel.WARN.
  39        max_unsupported: Maximum number of unsupported messages to include in a raised UnsupportedError.
  40            This is only relevant if unsupported_level is ErrorLevel.RAISE.
  41            Default: 3
  42        leading_comma: Determines whether or not the comma is leading or trailing in select expressions.
  43            This is only relevant when generating in pretty mode.
  44            Default: False
  45        max_text_width: The max number of characters in a segment before creating new lines in pretty mode.
  46            The default is on the smaller end because the length only represents a segment and not the true
  47            line length.
  48            Default: 80
  49        comments: Whether or not to preserve comments in the output SQL code.
  50            Default: True
  51    """
  52
  53    TRANSFORMS = {
  54        exp.DateAdd: lambda self, e: self.func(
  55            "DATE_ADD", e.this, e.expression, exp.Literal.string(e.text("unit"))
  56        ),
  57        exp.TsOrDsAdd: lambda self, e: self.func(
  58            "TS_OR_DS_ADD", e.this, e.expression, exp.Literal.string(e.text("unit"))
  59        ),
  60        exp.CaseSpecificColumnConstraint: lambda self, e: f"{'NOT ' if e.args.get('not_') else ''}CASESPECIFIC",
  61        exp.CharacterSetColumnConstraint: lambda self, e: f"CHARACTER SET {self.sql(e, 'this')}",
  62        exp.CharacterSetProperty: lambda self, e: f"{'DEFAULT ' if e.args.get('default') else ''}CHARACTER SET={self.sql(e, 'this')}",
  63        exp.CheckColumnConstraint: lambda self, e: f"CHECK ({self.sql(e, 'this')})",
  64        exp.CollateColumnConstraint: lambda self, e: f"COLLATE {self.sql(e, 'this')}",
  65        exp.CopyGrantsProperty: lambda self, e: "COPY GRANTS",
  66        exp.CommentColumnConstraint: lambda self, e: f"COMMENT {self.sql(e, 'this')}",
  67        exp.DateFormatColumnConstraint: lambda self, e: f"FORMAT {self.sql(e, 'this')}",
  68        exp.DefaultColumnConstraint: lambda self, e: f"DEFAULT {self.sql(e, 'this')}",
  69        exp.EncodeColumnConstraint: lambda self, e: f"ENCODE {self.sql(e, 'this')}",
  70        exp.ExecuteAsProperty: lambda self, e: self.naked_property(e),
  71        exp.ExternalProperty: lambda self, e: "EXTERNAL",
  72        exp.HeapProperty: lambda self, e: "HEAP",
  73        exp.InlineLengthColumnConstraint: lambda self, e: f"INLINE LENGTH {self.sql(e, 'this')}",
  74        exp.LanguageProperty: lambda self, e: self.naked_property(e),
  75        exp.LocationProperty: lambda self, e: self.naked_property(e),
  76        exp.LogProperty: lambda self, e: f"{'NO ' if e.args.get('no') else ''}LOG",
  77        exp.MaterializedProperty: lambda self, e: "MATERIALIZED",
  78        exp.NoPrimaryIndexProperty: lambda self, e: "NO PRIMARY INDEX",
  79        exp.OnCommitProperty: lambda self, e: f"ON COMMIT {'DELETE' if e.args.get('delete') else 'PRESERVE'} ROWS",
  80        exp.OnUpdateColumnConstraint: lambda self, e: f"ON UPDATE {self.sql(e, 'this')}",
  81        exp.PathColumnConstraint: lambda self, e: f"PATH {self.sql(e, 'this')}",
  82        exp.ReturnsProperty: lambda self, e: self.naked_property(e),
  83        exp.SetProperty: lambda self, e: f"{'MULTI' if e.args.get('multi') else ''}SET",
  84        exp.SettingsProperty: lambda self, e: f"SETTINGS{self.seg('')}{(self.expressions(e))}",
  85        exp.SqlSecurityProperty: lambda self, e: f"SQL SECURITY {'DEFINER' if e.args.get('definer') else 'INVOKER'}",
  86        exp.StabilityProperty: lambda self, e: e.name,
  87        exp.TemporaryProperty: lambda self, e: f"TEMPORARY",
  88        exp.ToTableProperty: lambda self, e: f"TO {self.sql(e.this)}",
  89        exp.TransientProperty: lambda self, e: "TRANSIENT",
  90        exp.TitleColumnConstraint: lambda self, e: f"TITLE {self.sql(e, 'this')}",
  91        exp.UppercaseColumnConstraint: lambda self, e: f"UPPERCASE",
  92        exp.VarMap: lambda self, e: self.func("MAP", e.args["keys"], e.args["values"]),
  93        exp.VolatileProperty: lambda self, e: "VOLATILE",
  94        exp.WithJournalTableProperty: lambda self, e: f"WITH JOURNAL TABLE={self.sql(e, 'this')}",
  95    }
  96
  97    # Whether or not null ordering is supported in order by
  98    NULL_ORDERING_SUPPORTED = True
  99
 100    # Whether or not locking reads (i.e. SELECT ... FOR UPDATE/SHARE) are supported
 101    LOCKING_READS_SUPPORTED = False
 102
 103    # Always do union distinct or union all
 104    EXPLICIT_UNION = False
 105
 106    # Wrap derived values in parens, usually standard but spark doesn't support it
 107    WRAP_DERIVED_VALUES = True
 108
 109    # Whether or not create function uses an AS before the RETURN
 110    CREATE_FUNCTION_RETURN_AS = True
 111
 112    # Whether or not MERGE ... WHEN MATCHED BY SOURCE is allowed
 113    MATCHED_BY_SOURCE = True
 114
 115    # Whether or not the INTERVAL expression works only with values like '1 day'
 116    SINGLE_STRING_INTERVAL = False
 117
 118    # Whether or not the plural form of date parts like day (i.e. "days") is supported in INTERVALs
 119    INTERVAL_ALLOWS_PLURAL_FORM = True
 120
 121    # Whether or not the TABLESAMPLE clause supports a method name, like BERNOULLI
 122    TABLESAMPLE_WITH_METHOD = True
 123
 124    # Whether or not to treat the number in TABLESAMPLE (50) as a percentage
 125    TABLESAMPLE_SIZE_IS_PERCENT = False
 126
 127    # Whether or not limit and fetch are supported (possible values: "ALL", "LIMIT", "FETCH")
 128    LIMIT_FETCH = "ALL"
 129
 130    # Whether or not a table is allowed to be renamed with a db
 131    RENAME_TABLE_WITH_DB = True
 132
 133    # The separator for grouping sets and rollups
 134    GROUPINGS_SEP = ","
 135
 136    # The string used for creating an index on a table
 137    INDEX_ON = "ON"
 138
 139    # Whether or not join hints should be generated
 140    JOIN_HINTS = True
 141
 142    # Whether or not table hints should be generated
 143    TABLE_HINTS = True
 144
 145    # Whether or not query hints should be generated
 146    QUERY_HINTS = True
 147
 148    # What kind of separator to use for query hints
 149    QUERY_HINT_SEP = ", "
 150
 151    # Whether or not comparing against booleans (e.g. x IS TRUE) is supported
 152    IS_BOOL_ALLOWED = True
 153
 154    # Whether or not to include the "SET" keyword in the "INSERT ... ON DUPLICATE KEY UPDATE" statement
 155    DUPLICATE_KEY_UPDATE_WITH_SET = True
 156
 157    # Whether or not to generate the limit as TOP <value> instead of LIMIT <value>
 158    LIMIT_IS_TOP = False
 159
 160    # Whether or not to generate INSERT INTO ... RETURNING or INSERT INTO RETURNING ...
 161    RETURNING_END = True
 162
 163    # Whether or not to generate the (+) suffix for columns used in old-style join conditions
 164    COLUMN_JOIN_MARKS_SUPPORTED = False
 165
 166    # Whether or not to generate an unquoted value for EXTRACT's date part argument
 167    EXTRACT_ALLOWS_QUOTES = True
 168
 169    # https://cloud.google.com/bigquery/docs/reference/standard-sql/query-syntax
 170    SELECT_KINDS: t.Tuple[str, ...] = ("STRUCT", "VALUE")
 171
 172    # Whether or not VALUES statements can be used as derived tables.
 173    # MySQL 5 and Redshift do not allow this, so when False, it will convert
 174    # SELECT * VALUES into SELECT UNION
 175    VALUES_AS_TABLE = True
 176
 177    TYPE_MAPPING = {
 178        exp.DataType.Type.NCHAR: "CHAR",
 179        exp.DataType.Type.NVARCHAR: "VARCHAR",
 180        exp.DataType.Type.MEDIUMTEXT: "TEXT",
 181        exp.DataType.Type.LONGTEXT: "TEXT",
 182        exp.DataType.Type.MEDIUMBLOB: "BLOB",
 183        exp.DataType.Type.LONGBLOB: "BLOB",
 184        exp.DataType.Type.INET: "INET",
 185    }
 186
 187    STAR_MAPPING = {
 188        "except": "EXCEPT",
 189        "replace": "REPLACE",
 190    }
 191
 192    TIME_PART_SINGULARS = {
 193        "microseconds": "microsecond",
 194        "seconds": "second",
 195        "minutes": "minute",
 196        "hours": "hour",
 197        "days": "day",
 198        "weeks": "week",
 199        "months": "month",
 200        "quarters": "quarter",
 201        "years": "year",
 202    }
 203
 204    TOKEN_MAPPING: t.Dict[TokenType, str] = {}
 205
 206    STRUCT_DELIMITER = ("<", ">")
 207
 208    PARAMETER_TOKEN = "@"
 209
 210    PROPERTIES_LOCATION = {
 211        exp.AlgorithmProperty: exp.Properties.Location.POST_CREATE,
 212        exp.AutoIncrementProperty: exp.Properties.Location.POST_SCHEMA,
 213        exp.BlockCompressionProperty: exp.Properties.Location.POST_NAME,
 214        exp.CharacterSetProperty: exp.Properties.Location.POST_SCHEMA,
 215        exp.ChecksumProperty: exp.Properties.Location.POST_NAME,
 216        exp.CollateProperty: exp.Properties.Location.POST_SCHEMA,
 217        exp.CopyGrantsProperty: exp.Properties.Location.POST_SCHEMA,
 218        exp.Cluster: exp.Properties.Location.POST_SCHEMA,
 219        exp.ClusteredByProperty: exp.Properties.Location.POST_SCHEMA,
 220        exp.DataBlocksizeProperty: exp.Properties.Location.POST_NAME,
 221        exp.DefinerProperty: exp.Properties.Location.POST_CREATE,
 222        exp.DictRange: exp.Properties.Location.POST_SCHEMA,
 223        exp.DictProperty: exp.Properties.Location.POST_SCHEMA,
 224        exp.DistKeyProperty: exp.Properties.Location.POST_SCHEMA,
 225        exp.DistStyleProperty: exp.Properties.Location.POST_SCHEMA,
 226        exp.EngineProperty: exp.Properties.Location.POST_SCHEMA,
 227        exp.ExecuteAsProperty: exp.Properties.Location.POST_SCHEMA,
 228        exp.ExternalProperty: exp.Properties.Location.POST_CREATE,
 229        exp.FallbackProperty: exp.Properties.Location.POST_NAME,
 230        exp.FileFormatProperty: exp.Properties.Location.POST_WITH,
 231        exp.FreespaceProperty: exp.Properties.Location.POST_NAME,
 232        exp.HeapProperty: exp.Properties.Location.POST_WITH,
 233        exp.IsolatedLoadingProperty: exp.Properties.Location.POST_NAME,
 234        exp.JournalProperty: exp.Properties.Location.POST_NAME,
 235        exp.LanguageProperty: exp.Properties.Location.POST_SCHEMA,
 236        exp.LikeProperty: exp.Properties.Location.POST_SCHEMA,
 237        exp.LocationProperty: exp.Properties.Location.POST_SCHEMA,
 238        exp.LockingProperty: exp.Properties.Location.POST_ALIAS,
 239        exp.LogProperty: exp.Properties.Location.POST_NAME,
 240        exp.MaterializedProperty: exp.Properties.Location.POST_CREATE,
 241        exp.MergeBlockRatioProperty: exp.Properties.Location.POST_NAME,
 242        exp.NoPrimaryIndexProperty: exp.Properties.Location.POST_EXPRESSION,
 243        exp.OnCommitProperty: exp.Properties.Location.POST_EXPRESSION,
 244        exp.Order: exp.Properties.Location.POST_SCHEMA,
 245        exp.PartitionedByProperty: exp.Properties.Location.POST_WITH,
 246        exp.PrimaryKey: exp.Properties.Location.POST_SCHEMA,
 247        exp.Property: exp.Properties.Location.POST_WITH,
 248        exp.ReturnsProperty: exp.Properties.Location.POST_SCHEMA,
 249        exp.RowFormatProperty: exp.Properties.Location.POST_SCHEMA,
 250        exp.RowFormatDelimitedProperty: exp.Properties.Location.POST_SCHEMA,
 251        exp.RowFormatSerdeProperty: exp.Properties.Location.POST_SCHEMA,
 252        exp.SchemaCommentProperty: exp.Properties.Location.POST_SCHEMA,
 253        exp.SerdeProperties: exp.Properties.Location.POST_SCHEMA,
 254        exp.Set: exp.Properties.Location.POST_SCHEMA,
 255        exp.SettingsProperty: exp.Properties.Location.POST_SCHEMA,
 256        exp.SetProperty: exp.Properties.Location.POST_CREATE,
 257        exp.SortKeyProperty: exp.Properties.Location.POST_SCHEMA,
 258        exp.SqlSecurityProperty: exp.Properties.Location.POST_CREATE,
 259        exp.StabilityProperty: exp.Properties.Location.POST_SCHEMA,
 260        exp.TemporaryProperty: exp.Properties.Location.POST_CREATE,
 261        exp.ToTableProperty: exp.Properties.Location.POST_SCHEMA,
 262        exp.TransientProperty: exp.Properties.Location.POST_CREATE,
 263        exp.MergeTreeTTL: exp.Properties.Location.POST_SCHEMA,
 264        exp.VolatileProperty: exp.Properties.Location.POST_CREATE,
 265        exp.WithDataProperty: exp.Properties.Location.POST_EXPRESSION,
 266        exp.WithJournalTableProperty: exp.Properties.Location.POST_NAME,
 267    }
 268
 269    # Keywords that can't be used as unquoted identifier names
 270    RESERVED_KEYWORDS: t.Set[str] = set()
 271
 272    # Expressions whose comments are separated from them for better formatting
 273    WITH_SEPARATED_COMMENTS: t.Tuple[t.Type[exp.Expression], ...] = (
 274        exp.Delete,
 275        exp.Drop,
 276        exp.From,
 277        exp.Insert,
 278        exp.Select,
 279        exp.Update,
 280        exp.Where,
 281        exp.With,
 282    )
 283
 284    # Expressions that can remain unwrapped when appearing in the context of an INTERVAL
 285    UNWRAPPED_INTERVAL_VALUES: t.Tuple[t.Type[exp.Expression], ...] = (
 286        exp.Column,
 287        exp.Literal,
 288        exp.Neg,
 289        exp.Paren,
 290    )
 291
 292    SENTINEL_LINE_BREAK = "__SQLGLOT__LB__"
 293
 294    # Autofilled
 295    INVERSE_TIME_MAPPING: t.Dict[str, str] = {}
 296    INVERSE_TIME_TRIE: t.Dict = {}
 297    INDEX_OFFSET = 0
 298    UNNEST_COLUMN_ONLY = False
 299    ALIAS_POST_TABLESAMPLE = False
 300    IDENTIFIERS_CAN_START_WITH_DIGIT = False
 301    STRICT_STRING_CONCAT = False
 302    NORMALIZE_FUNCTIONS: bool | str = "upper"
 303    NULL_ORDERING = "nulls_are_small"
 304    ESCAPE_LINE_BREAK = False
 305
 306    can_identify: t.Callable[[str, str | bool], bool]
 307
 308    # Delimiters for quotes, identifiers and the corresponding escape characters
 309    QUOTE_START = "'"
 310    QUOTE_END = "'"
 311    IDENTIFIER_START = '"'
 312    IDENTIFIER_END = '"'
 313    STRING_ESCAPE = "'"
 314    IDENTIFIER_ESCAPE = '"'
 315
 316    # Delimiters for bit, hex, byte and raw literals
 317    BIT_START: t.Optional[str] = None
 318    BIT_END: t.Optional[str] = None
 319    HEX_START: t.Optional[str] = None
 320    HEX_END: t.Optional[str] = None
 321    BYTE_START: t.Optional[str] = None
 322    BYTE_END: t.Optional[str] = None
 323
 324    __slots__ = (
 325        "pretty",
 326        "identify",
 327        "normalize",
 328        "pad",
 329        "_indent",
 330        "normalize_functions",
 331        "unsupported_level",
 332        "max_unsupported",
 333        "leading_comma",
 334        "max_text_width",
 335        "comments",
 336        "unsupported_messages",
 337        "_escaped_quote_end",
 338        "_escaped_identifier_end",
 339        "_cache",
 340    )
 341
 342    def __init__(
 343        self,
 344        pretty: t.Optional[bool] = None,
 345        identify: str | bool = False,
 346        normalize: bool = False,
 347        pad: int = 2,
 348        indent: int = 2,
 349        normalize_functions: t.Optional[str | bool] = None,
 350        unsupported_level: ErrorLevel = ErrorLevel.WARN,
 351        max_unsupported: int = 3,
 352        leading_comma: bool = False,
 353        max_text_width: int = 80,
 354        comments: bool = True,
 355    ):
 356        import sqlglot
 357
 358        self.pretty = pretty if pretty is not None else sqlglot.pretty
 359        self.identify = identify
 360        self.normalize = normalize
 361        self.pad = pad
 362        self._indent = indent
 363        self.unsupported_level = unsupported_level
 364        self.max_unsupported = max_unsupported
 365        self.leading_comma = leading_comma
 366        self.max_text_width = max_text_width
 367        self.comments = comments
 368
 369        # This is both a Dialect property and a Generator argument, so we prioritize the latter
 370        self.normalize_functions = (
 371            self.NORMALIZE_FUNCTIONS if normalize_functions is None else normalize_functions
 372        )
 373
 374        self.unsupported_messages: t.List[str] = []
 375        self._escaped_quote_end: str = self.STRING_ESCAPE + self.QUOTE_END
 376        self._escaped_identifier_end: str = self.IDENTIFIER_ESCAPE + self.IDENTIFIER_END
 377        self._cache: t.Optional[t.Dict[int, str]] = None
 378
 379    def generate(
 380        self,
 381        expression: t.Optional[exp.Expression],
 382        cache: t.Optional[t.Dict[int, str]] = None,
 383    ) -> str:
 384        """
 385        Generates the SQL string corresponding to the given syntax tree.
 386
 387        Args:
 388            expression: The syntax tree.
 389            cache: An optional sql string cache. This leverages the hash of an Expression
 390                which can be slow to compute, so only use it if you set _hash on each node.
 391
 392        Returns:
 393            The SQL string corresponding to `expression`.
 394        """
 395        if cache is not None:
 396            self._cache = cache
 397
 398        self.unsupported_messages = []
 399        sql = self.sql(expression).strip()
 400        self._cache = None
 401
 402        if self.unsupported_level == ErrorLevel.IGNORE:
 403            return sql
 404
 405        if self.unsupported_level == ErrorLevel.WARN:
 406            for msg in self.unsupported_messages:
 407                logger.warning(msg)
 408        elif self.unsupported_level == ErrorLevel.RAISE and self.unsupported_messages:
 409            raise UnsupportedError(concat_messages(self.unsupported_messages, self.max_unsupported))
 410
 411        if self.pretty:
 412            sql = sql.replace(self.SENTINEL_LINE_BREAK, "\n")
 413        return sql
 414
 415    def unsupported(self, message: str) -> None:
 416        if self.unsupported_level == ErrorLevel.IMMEDIATE:
 417            raise UnsupportedError(message)
 418        self.unsupported_messages.append(message)
 419
 420    def sep(self, sep: str = " ") -> str:
 421        return f"{sep.strip()}\n" if self.pretty else sep
 422
 423    def seg(self, sql: str, sep: str = " ") -> str:
 424        return f"{self.sep(sep)}{sql}"
 425
 426    def pad_comment(self, comment: str) -> str:
 427        comment = " " + comment if comment[0].strip() else comment
 428        comment = comment + " " if comment[-1].strip() else comment
 429        return comment
 430
 431    def maybe_comment(
 432        self,
 433        sql: str,
 434        expression: t.Optional[exp.Expression] = None,
 435        comments: t.Optional[t.List[str]] = None,
 436    ) -> str:
 437        comments = (
 438            ((expression and expression.comments) if comments is None else comments)  # type: ignore
 439            if self.comments
 440            else None
 441        )
 442
 443        if not comments or isinstance(expression, exp.Binary):
 444            return sql
 445
 446        sep = "\n" if self.pretty else " "
 447        comments_sql = sep.join(
 448            f"/*{self.pad_comment(comment)}*/" for comment in comments if comment
 449        )
 450
 451        if not comments_sql:
 452            return sql
 453
 454        if isinstance(expression, self.WITH_SEPARATED_COMMENTS):
 455            return (
 456                f"{self.sep()}{comments_sql}{sql}"
 457                if sql[0].isspace()
 458                else f"{comments_sql}{self.sep()}{sql}"
 459            )
 460
 461        return f"{sql} {comments_sql}"
 462
 463    def wrap(self, expression: exp.Expression | str) -> str:
 464        this_sql = self.indent(
 465            self.sql(expression)
 466            if isinstance(expression, (exp.Select, exp.Union))
 467            else self.sql(expression, "this"),
 468            level=1,
 469            pad=0,
 470        )
 471        return f"({self.sep('')}{this_sql}{self.seg(')', sep='')}"
 472
 473    def no_identify(self, func: t.Callable[..., str], *args, **kwargs) -> str:
 474        original = self.identify
 475        self.identify = False
 476        result = func(*args, **kwargs)
 477        self.identify = original
 478        return result
 479
 480    def normalize_func(self, name: str) -> str:
 481        if self.normalize_functions == "upper" or self.normalize_functions is True:
 482            return name.upper()
 483        if self.normalize_functions == "lower":
 484            return name.lower()
 485        return name
 486
 487    def indent(
 488        self,
 489        sql: str,
 490        level: int = 0,
 491        pad: t.Optional[int] = None,
 492        skip_first: bool = False,
 493        skip_last: bool = False,
 494    ) -> str:
 495        if not self.pretty:
 496            return sql
 497
 498        pad = self.pad if pad is None else pad
 499        lines = sql.split("\n")
 500
 501        return "\n".join(
 502            line
 503            if (skip_first and i == 0) or (skip_last and i == len(lines) - 1)
 504            else f"{' ' * (level * self._indent + pad)}{line}"
 505            for i, line in enumerate(lines)
 506        )
 507
 508    def sql(
 509        self,
 510        expression: t.Optional[str | exp.Expression],
 511        key: t.Optional[str] = None,
 512        comment: bool = True,
 513    ) -> str:
 514        if not expression:
 515            return ""
 516
 517        if isinstance(expression, str):
 518            return expression
 519
 520        if key:
 521            value = expression.args.get(key)
 522            if value:
 523                return self.sql(value)
 524            return ""
 525
 526        if self._cache is not None:
 527            expression_id = hash(expression)
 528
 529            if expression_id in self._cache:
 530                return self._cache[expression_id]
 531
 532        transform = self.TRANSFORMS.get(expression.__class__)
 533
 534        if callable(transform):
 535            sql = transform(self, expression)
 536        elif transform:
 537            sql = transform
 538        elif isinstance(expression, exp.Expression):
 539            exp_handler_name = f"{expression.key}_sql"
 540
 541            if hasattr(self, exp_handler_name):
 542                sql = getattr(self, exp_handler_name)(expression)
 543            elif isinstance(expression, exp.Func):
 544                sql = self.function_fallback_sql(expression)
 545            elif isinstance(expression, exp.Property):
 546                sql = self.property_sql(expression)
 547            else:
 548                raise ValueError(f"Unsupported expression type {expression.__class__.__name__}")
 549        else:
 550            raise ValueError(f"Expected an Expression. Received {type(expression)}: {expression}")
 551
 552        sql = self.maybe_comment(sql, expression) if self.comments and comment else sql
 553
 554        if self._cache is not None:
 555            self._cache[expression_id] = sql
 556        return sql
 557
 558    def uncache_sql(self, expression: exp.Uncache) -> str:
 559        table = self.sql(expression, "this")
 560        exists_sql = " IF EXISTS" if expression.args.get("exists") else ""
 561        return f"UNCACHE TABLE{exists_sql} {table}"
 562
 563    def cache_sql(self, expression: exp.Cache) -> str:
 564        lazy = " LAZY" if expression.args.get("lazy") else ""
 565        table = self.sql(expression, "this")
 566        options = expression.args.get("options")
 567        options = f" OPTIONS({self.sql(options[0])} = {self.sql(options[1])})" if options else ""
 568        sql = self.sql(expression, "expression")
 569        sql = f" AS{self.sep()}{sql}" if sql else ""
 570        sql = f"CACHE{lazy} TABLE {table}{options}{sql}"
 571        return self.prepend_ctes(expression, sql)
 572
 573    def characterset_sql(self, expression: exp.CharacterSet) -> str:
 574        if isinstance(expression.parent, exp.Cast):
 575            return f"CHAR CHARACTER SET {self.sql(expression, 'this')}"
 576        default = "DEFAULT " if expression.args.get("default") else ""
 577        return f"{default}CHARACTER SET={self.sql(expression, 'this')}"
 578
 579    def column_sql(self, expression: exp.Column) -> str:
 580        join_mark = " (+)" if expression.args.get("join_mark") else ""
 581
 582        if join_mark and not self.COLUMN_JOIN_MARKS_SUPPORTED:
 583            join_mark = ""
 584            self.unsupported("Outer join syntax using the (+) operator is not supported.")
 585
 586        column = ".".join(
 587            self.sql(part)
 588            for part in (
 589                expression.args.get("catalog"),
 590                expression.args.get("db"),
 591                expression.args.get("table"),
 592                expression.args.get("this"),
 593            )
 594            if part
 595        )
 596
 597        return f"{column}{join_mark}"
 598
 599    def columnposition_sql(self, expression: exp.ColumnPosition) -> str:
 600        this = self.sql(expression, "this")
 601        this = f" {this}" if this else ""
 602        position = self.sql(expression, "position")
 603        return f"{position}{this}"
 604
 605    def columndef_sql(self, expression: exp.ColumnDef, sep: str = " ") -> str:
 606        column = self.sql(expression, "this")
 607        kind = self.sql(expression, "kind")
 608        constraints = self.expressions(expression, key="constraints", sep=" ", flat=True)
 609        exists = "IF NOT EXISTS " if expression.args.get("exists") else ""
 610        kind = f"{sep}{kind}" if kind else ""
 611        constraints = f" {constraints}" if constraints else ""
 612        position = self.sql(expression, "position")
 613        position = f" {position}" if position else ""
 614
 615        return f"{exists}{column}{kind}{constraints}{position}"
 616
 617    def columnconstraint_sql(self, expression: exp.ColumnConstraint) -> str:
 618        this = self.sql(expression, "this")
 619        kind_sql = self.sql(expression, "kind").strip()
 620        return f"CONSTRAINT {this} {kind_sql}" if this else kind_sql
 621
 622    def autoincrementcolumnconstraint_sql(self, _) -> str:
 623        return self.token_sql(TokenType.AUTO_INCREMENT)
 624
 625    def compresscolumnconstraint_sql(self, expression: exp.CompressColumnConstraint) -> str:
 626        if isinstance(expression.this, list):
 627            this = self.wrap(self.expressions(expression, key="this", flat=True))
 628        else:
 629            this = self.sql(expression, "this")
 630
 631        return f"COMPRESS {this}"
 632
 633    def generatedasidentitycolumnconstraint_sql(
 634        self, expression: exp.GeneratedAsIdentityColumnConstraint
 635    ) -> str:
 636        this = ""
 637        if expression.this is not None:
 638            on_null = "ON NULL " if expression.args.get("on_null") else ""
 639            this = " ALWAYS " if expression.this else f" BY DEFAULT {on_null}"
 640
 641        start = expression.args.get("start")
 642        start = f"START WITH {start}" if start else ""
 643        increment = expression.args.get("increment")
 644        increment = f" INCREMENT BY {increment}" if increment else ""
 645        minvalue = expression.args.get("minvalue")
 646        minvalue = f" MINVALUE {minvalue}" if minvalue else ""
 647        maxvalue = expression.args.get("maxvalue")
 648        maxvalue = f" MAXVALUE {maxvalue}" if maxvalue else ""
 649        cycle = expression.args.get("cycle")
 650        cycle_sql = ""
 651
 652        if cycle is not None:
 653            cycle_sql = f"{' NO' if not cycle else ''} CYCLE"
 654            cycle_sql = cycle_sql.strip() if not start and not increment else cycle_sql
 655
 656        sequence_opts = ""
 657        if start or increment or cycle_sql:
 658            sequence_opts = f"{start}{increment}{minvalue}{maxvalue}{cycle_sql}"
 659            sequence_opts = f" ({sequence_opts.strip()})"
 660
 661        expr = self.sql(expression, "expression")
 662        expr = f"({expr})" if expr else "IDENTITY"
 663
 664        return f"GENERATED{this}AS {expr}{sequence_opts}"
 665
 666    def notnullcolumnconstraint_sql(self, expression: exp.NotNullColumnConstraint) -> str:
 667        return f"{'' if expression.args.get('allow_null') else 'NOT '}NULL"
 668
 669    def primarykeycolumnconstraint_sql(self, expression: exp.PrimaryKeyColumnConstraint) -> str:
 670        desc = expression.args.get("desc")
 671        if desc is not None:
 672            return f"PRIMARY KEY{' DESC' if desc else ' ASC'}"
 673        return f"PRIMARY KEY"
 674
 675    def uniquecolumnconstraint_sql(self, expression: exp.UniqueColumnConstraint) -> str:
 676        this = self.sql(expression, "this")
 677        this = f" {this}" if this else ""
 678        return f"UNIQUE{this}"
 679
 680    def createable_sql(self, expression: exp.Create, locations: t.DefaultDict) -> str:
 681        return self.sql(expression, "this")
 682
 683    def create_sql(self, expression: exp.Create) -> str:
 684        kind = self.sql(expression, "kind").upper()
 685        properties = expression.args.get("properties")
 686        properties_locs = self.locate_properties(properties) if properties else defaultdict()
 687
 688        this = self.createable_sql(expression, properties_locs)
 689
 690        properties_sql = ""
 691        if properties_locs.get(exp.Properties.Location.POST_SCHEMA) or properties_locs.get(
 692            exp.Properties.Location.POST_WITH
 693        ):
 694            properties_sql = self.sql(
 695                exp.Properties(
 696                    expressions=[
 697                        *properties_locs[exp.Properties.Location.POST_SCHEMA],
 698                        *properties_locs[exp.Properties.Location.POST_WITH],
 699                    ]
 700                )
 701            )
 702
 703        begin = " BEGIN" if expression.args.get("begin") else ""
 704        expression_sql = self.sql(expression, "expression")
 705        if expression_sql:
 706            expression_sql = f"{begin}{self.sep()}{expression_sql}"
 707
 708            if self.CREATE_FUNCTION_RETURN_AS or not isinstance(expression.expression, exp.Return):
 709                if properties_locs.get(exp.Properties.Location.POST_ALIAS):
 710                    postalias_props_sql = self.properties(
 711                        exp.Properties(
 712                            expressions=properties_locs[exp.Properties.Location.POST_ALIAS]
 713                        ),
 714                        wrapped=False,
 715                    )
 716                    expression_sql = f" AS {postalias_props_sql}{expression_sql}"
 717                else:
 718                    expression_sql = f" AS{expression_sql}"
 719
 720        postindex_props_sql = ""
 721        if properties_locs.get(exp.Properties.Location.POST_INDEX):
 722            postindex_props_sql = self.properties(
 723                exp.Properties(expressions=properties_locs[exp.Properties.Location.POST_INDEX]),
 724                wrapped=False,
 725                prefix=" ",
 726            )
 727
 728        indexes = self.expressions(expression, key="indexes", indent=False, sep=" ")
 729        indexes = f" {indexes}" if indexes else ""
 730        index_sql = indexes + postindex_props_sql
 731
 732        replace = " OR REPLACE" if expression.args.get("replace") else ""
 733        unique = " UNIQUE" if expression.args.get("unique") else ""
 734
 735        postcreate_props_sql = ""
 736        if properties_locs.get(exp.Properties.Location.POST_CREATE):
 737            postcreate_props_sql = self.properties(
 738                exp.Properties(expressions=properties_locs[exp.Properties.Location.POST_CREATE]),
 739                sep=" ",
 740                prefix=" ",
 741                wrapped=False,
 742            )
 743
 744        modifiers = "".join((replace, unique, postcreate_props_sql))
 745
 746        postexpression_props_sql = ""
 747        if properties_locs.get(exp.Properties.Location.POST_EXPRESSION):
 748            postexpression_props_sql = self.properties(
 749                exp.Properties(
 750                    expressions=properties_locs[exp.Properties.Location.POST_EXPRESSION]
 751                ),
 752                sep=" ",
 753                prefix=" ",
 754                wrapped=False,
 755            )
 756
 757        exists_sql = " IF NOT EXISTS" if expression.args.get("exists") else ""
 758        no_schema_binding = (
 759            " WITH NO SCHEMA BINDING" if expression.args.get("no_schema_binding") else ""
 760        )
 761
 762        clone = self.sql(expression, "clone")
 763        clone = f" {clone}" if clone else ""
 764
 765        expression_sql = f"CREATE{modifiers} {kind}{exists_sql} {this}{properties_sql}{expression_sql}{postexpression_props_sql}{index_sql}{no_schema_binding}{clone}"
 766        return self.prepend_ctes(expression, expression_sql)
 767
 768    def clone_sql(self, expression: exp.Clone) -> str:
 769        this = self.sql(expression, "this")
 770        when = self.sql(expression, "when")
 771
 772        if when:
 773            kind = self.sql(expression, "kind")
 774            expr = self.sql(expression, "expression")
 775            return f"CLONE {this} {when} ({kind} => {expr})"
 776
 777        return f"CLONE {this}"
 778
 779    def describe_sql(self, expression: exp.Describe) -> str:
 780        return f"DESCRIBE {self.sql(expression, 'this')}"
 781
 782    def prepend_ctes(self, expression: exp.Expression, sql: str) -> str:
 783        with_ = self.sql(expression, "with")
 784        if with_:
 785            sql = f"{with_}{self.sep()}{sql}"
 786        return sql
 787
 788    def with_sql(self, expression: exp.With) -> str:
 789        sql = self.expressions(expression, flat=True)
 790        recursive = "RECURSIVE " if expression.args.get("recursive") else ""
 791
 792        return f"WITH {recursive}{sql}"
 793
 794    def cte_sql(self, expression: exp.CTE) -> str:
 795        alias = self.sql(expression, "alias")
 796        return f"{alias} AS {self.wrap(expression)}"
 797
 798    def tablealias_sql(self, expression: exp.TableAlias) -> str:
 799        alias = self.sql(expression, "this")
 800        columns = self.expressions(expression, key="columns", flat=True)
 801        columns = f"({columns})" if columns else ""
 802        return f"{alias}{columns}"
 803
 804    def bitstring_sql(self, expression: exp.BitString) -> str:
 805        this = self.sql(expression, "this")
 806        if self.BIT_START:
 807            return f"{self.BIT_START}{this}{self.BIT_END}"
 808        return f"{int(this, 2)}"
 809
 810    def hexstring_sql(self, expression: exp.HexString) -> str:
 811        this = self.sql(expression, "this")
 812        if self.HEX_START:
 813            return f"{self.HEX_START}{this}{self.HEX_END}"
 814        return f"{int(this, 16)}"
 815
 816    def bytestring_sql(self, expression: exp.ByteString) -> str:
 817        this = self.sql(expression, "this")
 818        if self.BYTE_START:
 819            return f"{self.BYTE_START}{this}{self.BYTE_END}"
 820        return this
 821
 822    def rawstring_sql(self, expression: exp.RawString) -> str:
 823        string = self.escape_str(expression.this.replace("\\", "\\\\"))
 824        return f"{self.QUOTE_START}{string}{self.QUOTE_END}"
 825
 826    def datatypesize_sql(self, expression: exp.DataTypeSize) -> str:
 827        this = self.sql(expression, "this")
 828        specifier = self.sql(expression, "expression")
 829        specifier = f" {specifier}" if specifier else ""
 830        return f"{this}{specifier}"
 831
 832    def datatype_sql(self, expression: exp.DataType) -> str:
 833        type_value = expression.this
 834        type_sql = (
 835            self.TYPE_MAPPING.get(type_value, type_value.value)
 836            if isinstance(type_value, exp.DataType.Type)
 837            else type_value
 838        )
 839        nested = ""
 840        interior = self.expressions(expression, flat=True)
 841        values = ""
 842        if interior:
 843            if expression.args.get("nested"):
 844                nested = f"{self.STRUCT_DELIMITER[0]}{interior}{self.STRUCT_DELIMITER[1]}"
 845                if expression.args.get("values") is not None:
 846                    delimiters = ("[", "]") if type_value == exp.DataType.Type.ARRAY else ("(", ")")
 847                    values = self.expressions(expression, key="values", flat=True)
 848                    values = f"{delimiters[0]}{values}{delimiters[1]}"
 849            else:
 850                nested = f"({interior})"
 851
 852        return f"{type_sql}{nested}{values}"
 853
 854    def directory_sql(self, expression: exp.Directory) -> str:
 855        local = "LOCAL " if expression.args.get("local") else ""
 856        row_format = self.sql(expression, "row_format")
 857        row_format = f" {row_format}" if row_format else ""
 858        return f"{local}DIRECTORY {self.sql(expression, 'this')}{row_format}"
 859
 860    def delete_sql(self, expression: exp.Delete) -> str:
 861        this = self.sql(expression, "this")
 862        this = f" FROM {this}" if this else ""
 863        using = self.sql(expression, "using")
 864        using = f" USING {using}" if using else ""
 865        where = self.sql(expression, "where")
 866        returning = self.sql(expression, "returning")
 867        limit = self.sql(expression, "limit")
 868        tables = self.expressions(expression, key="tables")
 869        tables = f" {tables}" if tables else ""
 870        if self.RETURNING_END:
 871            expression_sql = f"{this}{using}{where}{returning}{limit}"
 872        else:
 873            expression_sql = f"{returning}{this}{using}{where}{limit}"
 874        return self.prepend_ctes(expression, f"DELETE{tables}{expression_sql}")
 875
 876    def drop_sql(self, expression: exp.Drop) -> str:
 877        this = self.sql(expression, "this")
 878        kind = expression.args["kind"]
 879        exists_sql = " IF EXISTS " if expression.args.get("exists") else " "
 880        temporary = " TEMPORARY" if expression.args.get("temporary") else ""
 881        materialized = " MATERIALIZED" if expression.args.get("materialized") else ""
 882        cascade = " CASCADE" if expression.args.get("cascade") else ""
 883        constraints = " CONSTRAINTS" if expression.args.get("constraints") else ""
 884        purge = " PURGE" if expression.args.get("purge") else ""
 885        return (
 886            f"DROP{temporary}{materialized} {kind}{exists_sql}{this}{cascade}{constraints}{purge}"
 887        )
 888
 889    def except_sql(self, expression: exp.Except) -> str:
 890        return self.prepend_ctes(
 891            expression,
 892            self.set_operation(expression, self.except_op(expression)),
 893        )
 894
 895    def except_op(self, expression: exp.Except) -> str:
 896        return f"EXCEPT{'' if expression.args.get('distinct') else ' ALL'}"
 897
 898    def fetch_sql(self, expression: exp.Fetch) -> str:
 899        direction = expression.args.get("direction")
 900        direction = f" {direction.upper()}" if direction else ""
 901        count = expression.args.get("count")
 902        count = f" {count}" if count else ""
 903        if expression.args.get("percent"):
 904            count = f"{count} PERCENT"
 905        with_ties_or_only = "WITH TIES" if expression.args.get("with_ties") else "ONLY"
 906        return f"{self.seg('FETCH')}{direction}{count} ROWS {with_ties_or_only}"
 907
 908    def filter_sql(self, expression: exp.Filter) -> str:
 909        this = self.sql(expression, "this")
 910        where = self.sql(expression, "expression")[1:]  # where has a leading space
 911        return f"{this} FILTER({where})"
 912
 913    def hint_sql(self, expression: exp.Hint) -> str:
 914        if not self.QUERY_HINTS:
 915            self.unsupported("Hints are not supported")
 916            return ""
 917
 918        return f" /*+ {self.expressions(expression, sep=self.QUERY_HINT_SEP).strip()} */"
 919
 920    def index_sql(self, expression: exp.Index) -> str:
 921        unique = "UNIQUE " if expression.args.get("unique") else ""
 922        primary = "PRIMARY " if expression.args.get("primary") else ""
 923        amp = "AMP " if expression.args.get("amp") else ""
 924        name = self.sql(expression, "this")
 925        name = f"{name} " if name else ""
 926        table = self.sql(expression, "table")
 927        table = f"{self.INDEX_ON} {table} " if table else ""
 928        using = self.sql(expression, "using")
 929        using = f"USING {using} " if using else ""
 930        index = "INDEX " if not table else ""
 931        columns = self.expressions(expression, key="columns", flat=True)
 932        columns = f"({columns})" if columns else ""
 933        partition_by = self.expressions(expression, key="partition_by", flat=True)
 934        partition_by = f" PARTITION BY {partition_by}" if partition_by else ""
 935        return f"{unique}{primary}{amp}{index}{name}{table}{using}{columns}{partition_by}"
 936
 937    def identifier_sql(self, expression: exp.Identifier) -> str:
 938        text = expression.name
 939        lower = text.lower()
 940        text = lower if self.normalize and not expression.quoted else text
 941        text = text.replace(self.IDENTIFIER_END, self._escaped_identifier_end)
 942        if (
 943            expression.quoted
 944            or self.can_identify(text, self.identify)
 945            or lower in self.RESERVED_KEYWORDS
 946            or (not self.IDENTIFIERS_CAN_START_WITH_DIGIT and text[:1].isdigit())
 947        ):
 948            text = f"{self.IDENTIFIER_START}{text}{self.IDENTIFIER_END}"
 949        return text
 950
 951    def inputoutputformat_sql(self, expression: exp.InputOutputFormat) -> str:
 952        input_format = self.sql(expression, "input_format")
 953        input_format = f"INPUTFORMAT {input_format}" if input_format else ""
 954        output_format = self.sql(expression, "output_format")
 955        output_format = f"OUTPUTFORMAT {output_format}" if output_format else ""
 956        return self.sep().join((input_format, output_format))
 957
 958    def national_sql(self, expression: exp.National, prefix: str = "N") -> str:
 959        string = self.sql(exp.Literal.string(expression.name))
 960        return f"{prefix}{string}"
 961
 962    def partition_sql(self, expression: exp.Partition) -> str:
 963        return f"PARTITION({self.expressions(expression, flat=True)})"
 964
 965    def properties_sql(self, expression: exp.Properties) -> str:
 966        root_properties = []
 967        with_properties = []
 968
 969        for p in expression.expressions:
 970            p_loc = self.PROPERTIES_LOCATION[p.__class__]
 971            if p_loc == exp.Properties.Location.POST_WITH:
 972                with_properties.append(p.copy())
 973            elif p_loc == exp.Properties.Location.POST_SCHEMA:
 974                root_properties.append(p.copy())
 975
 976        return self.root_properties(
 977            exp.Properties(expressions=root_properties)
 978        ) + self.with_properties(exp.Properties(expressions=with_properties))
 979
 980    def root_properties(self, properties: exp.Properties) -> str:
 981        if properties.expressions:
 982            return self.sep() + self.expressions(properties, indent=False, sep=" ")
 983        return ""
 984
 985    def properties(
 986        self,
 987        properties: exp.Properties,
 988        prefix: str = "",
 989        sep: str = ", ",
 990        suffix: str = "",
 991        wrapped: bool = True,
 992    ) -> str:
 993        if properties.expressions:
 994            expressions = self.expressions(properties, sep=sep, indent=False)
 995            if expressions:
 996                expressions = self.wrap(expressions) if wrapped else expressions
 997                return f"{prefix}{' ' if prefix and prefix != ' ' else ''}{expressions}{suffix}"
 998        return ""
 999
1000    def with_properties(self, properties: exp.Properties) -> str:
1001        return self.properties(properties, prefix=self.seg("WITH"))
1002
1003    def locate_properties(self, properties: exp.Properties) -> t.DefaultDict:
1004        properties_locs = defaultdict(list)
1005        for p in properties.expressions:
1006            p_loc = self.PROPERTIES_LOCATION[p.__class__]
1007            if p_loc != exp.Properties.Location.UNSUPPORTED:
1008                properties_locs[p_loc].append(p.copy())
1009            else:
1010                self.unsupported(f"Unsupported property {p.key}")
1011
1012        return properties_locs
1013
1014    def property_sql(self, expression: exp.Property) -> str:
1015        property_cls = expression.__class__
1016        if property_cls == exp.Property:
1017            return f"{expression.name}={self.sql(expression, 'value')}"
1018
1019        property_name = exp.Properties.PROPERTY_TO_NAME.get(property_cls)
1020        if not property_name:
1021            self.unsupported(f"Unsupported property {expression.key}")
1022
1023        return f"{property_name}={self.sql(expression, 'this')}"
1024
1025    def likeproperty_sql(self, expression: exp.LikeProperty) -> str:
1026        options = " ".join(f"{e.name} {self.sql(e, 'value')}" for e in expression.expressions)
1027        options = f" {options}" if options else ""
1028        return f"LIKE {self.sql(expression, 'this')}{options}"
1029
1030    def fallbackproperty_sql(self, expression: exp.FallbackProperty) -> str:
1031        no = "NO " if expression.args.get("no") else ""
1032        protection = " PROTECTION" if expression.args.get("protection") else ""
1033        return f"{no}FALLBACK{protection}"
1034
1035    def journalproperty_sql(self, expression: exp.JournalProperty) -> str:
1036        no = "NO " if expression.args.get("no") else ""
1037        local = expression.args.get("local")
1038        local = f"{local} " if local else ""
1039        dual = "DUAL " if expression.args.get("dual") else ""
1040        before = "BEFORE " if expression.args.get("before") else ""
1041        after = "AFTER " if expression.args.get("after") else ""
1042        return f"{no}{local}{dual}{before}{after}JOURNAL"
1043
1044    def freespaceproperty_sql(self, expression: exp.FreespaceProperty) -> str:
1045        freespace = self.sql(expression, "this")
1046        percent = " PERCENT" if expression.args.get("percent") else ""
1047        return f"FREESPACE={freespace}{percent}"
1048
1049    def checksumproperty_sql(self, expression: exp.ChecksumProperty) -> str:
1050        if expression.args.get("default"):
1051            property = "DEFAULT"
1052        elif expression.args.get("on"):
1053            property = "ON"
1054        else:
1055            property = "OFF"
1056        return f"CHECKSUM={property}"
1057
1058    def mergeblockratioproperty_sql(self, expression: exp.MergeBlockRatioProperty) -> str:
1059        if expression.args.get("no"):
1060            return "NO MERGEBLOCKRATIO"
1061        if expression.args.get("default"):
1062            return "DEFAULT MERGEBLOCKRATIO"
1063
1064        percent = " PERCENT" if expression.args.get("percent") else ""
1065        return f"MERGEBLOCKRATIO={self.sql(expression, 'this')}{percent}"
1066
1067    def datablocksizeproperty_sql(self, expression: exp.DataBlocksizeProperty) -> str:
1068        default = expression.args.get("default")
1069        minimum = expression.args.get("minimum")
1070        maximum = expression.args.get("maximum")
1071        if default or minimum or maximum:
1072            if default:
1073                prop = "DEFAULT"
1074            elif minimum:
1075                prop = "MINIMUM"
1076            else:
1077                prop = "MAXIMUM"
1078            return f"{prop} DATABLOCKSIZE"
1079        units = expression.args.get("units")
1080        units = f" {units}" if units else ""
1081        return f"DATABLOCKSIZE={self.sql(expression, 'size')}{units}"
1082
1083    def blockcompressionproperty_sql(self, expression: exp.BlockCompressionProperty) -> str:
1084        autotemp = expression.args.get("autotemp")
1085        always = expression.args.get("always")
1086        default = expression.args.get("default")
1087        manual = expression.args.get("manual")
1088        never = expression.args.get("never")
1089
1090        if autotemp is not None:
1091            prop = f"AUTOTEMP({self.expressions(autotemp)})"
1092        elif always:
1093            prop = "ALWAYS"
1094        elif default:
1095            prop = "DEFAULT"
1096        elif manual:
1097            prop = "MANUAL"
1098        elif never:
1099            prop = "NEVER"
1100        return f"BLOCKCOMPRESSION={prop}"
1101
1102    def isolatedloadingproperty_sql(self, expression: exp.IsolatedLoadingProperty) -> str:
1103        no = expression.args.get("no")
1104        no = " NO" if no else ""
1105        concurrent = expression.args.get("concurrent")
1106        concurrent = " CONCURRENT" if concurrent else ""
1107
1108        for_ = ""
1109        if expression.args.get("for_all"):
1110            for_ = " FOR ALL"
1111        elif expression.args.get("for_insert"):
1112            for_ = " FOR INSERT"
1113        elif expression.args.get("for_none"):
1114            for_ = " FOR NONE"
1115        return f"WITH{no}{concurrent} ISOLATED LOADING{for_}"
1116
1117    def lockingproperty_sql(self, expression: exp.LockingProperty) -> str:
1118        kind = expression.args.get("kind")
1119        this = f" {self.sql(expression, 'this')}" if expression.this else ""
1120        for_or_in = expression.args.get("for_or_in")
1121        lock_type = expression.args.get("lock_type")
1122        override = " OVERRIDE" if expression.args.get("override") else ""
1123        return f"LOCKING {kind}{this} {for_or_in} {lock_type}{override}"
1124
1125    def withdataproperty_sql(self, expression: exp.WithDataProperty) -> str:
1126        data_sql = f"WITH {'NO ' if expression.args.get('no') else ''}DATA"
1127        statistics = expression.args.get("statistics")
1128        statistics_sql = ""
1129        if statistics is not None:
1130            statistics_sql = f" AND {'NO ' if not statistics else ''}STATISTICS"
1131        return f"{data_sql}{statistics_sql}"
1132
1133    def insert_sql(self, expression: exp.Insert) -> str:
1134        overwrite = expression.args.get("overwrite")
1135
1136        if isinstance(expression.this, exp.Directory):
1137            this = " OVERWRITE" if overwrite else " INTO"
1138        else:
1139            this = " OVERWRITE TABLE" if overwrite else " INTO"
1140
1141        alternative = expression.args.get("alternative")
1142        alternative = f" OR {alternative}" if alternative else ""
1143        ignore = " IGNORE" if expression.args.get("ignore") else ""
1144
1145        this = f"{this} {self.sql(expression, 'this')}"
1146
1147        exists = " IF EXISTS" if expression.args.get("exists") else ""
1148        partition_sql = (
1149            f" {self.sql(expression, 'partition')}" if expression.args.get("partition") else ""
1150        )
1151        where = self.sql(expression, "where")
1152        where = f"{self.sep()}REPLACE WHERE {where}" if where else ""
1153        expression_sql = f"{self.sep()}{self.sql(expression, 'expression')}"
1154        conflict = self.sql(expression, "conflict")
1155        returning = self.sql(expression, "returning")
1156
1157        if self.RETURNING_END:
1158            expression_sql = f"{expression_sql}{conflict}{returning}"
1159        else:
1160            expression_sql = f"{returning}{expression_sql}{conflict}"
1161
1162        sql = f"INSERT{alternative}{ignore}{this}{exists}{partition_sql}{where}{expression_sql}"
1163        return self.prepend_ctes(expression, sql)
1164
1165    def intersect_sql(self, expression: exp.Intersect) -> str:
1166        return self.prepend_ctes(
1167            expression,
1168            self.set_operation(expression, self.intersect_op(expression)),
1169        )
1170
1171    def intersect_op(self, expression: exp.Intersect) -> str:
1172        return f"INTERSECT{'' if expression.args.get('distinct') else ' ALL'}"
1173
1174    def introducer_sql(self, expression: exp.Introducer) -> str:
1175        return f"{self.sql(expression, 'this')} {self.sql(expression, 'expression')}"
1176
1177    def pseudotype_sql(self, expression: exp.PseudoType) -> str:
1178        return expression.name.upper()
1179
1180    def onconflict_sql(self, expression: exp.OnConflict) -> str:
1181        conflict = "ON DUPLICATE KEY" if expression.args.get("duplicate") else "ON CONFLICT"
1182        constraint = self.sql(expression, "constraint")
1183        if constraint:
1184            constraint = f"ON CONSTRAINT {constraint}"
1185        key = self.expressions(expression, key="key", flat=True)
1186        do = "" if expression.args.get("duplicate") else " DO "
1187        nothing = "NOTHING" if expression.args.get("nothing") else ""
1188        expressions = self.expressions(expression, flat=True)
1189        set_keyword = "SET " if self.DUPLICATE_KEY_UPDATE_WITH_SET else ""
1190        if expressions:
1191            expressions = f"UPDATE {set_keyword}{expressions}"
1192        return f"{self.seg(conflict)} {constraint}{key}{do}{nothing}{expressions}"
1193
1194    def returning_sql(self, expression: exp.Returning) -> str:
1195        return f"{self.seg('RETURNING')} {self.expressions(expression, flat=True)}"
1196
1197    def rowformatdelimitedproperty_sql(self, expression: exp.RowFormatDelimitedProperty) -> str:
1198        fields = expression.args.get("fields")
1199        fields = f" FIELDS TERMINATED BY {fields}" if fields else ""
1200        escaped = expression.args.get("escaped")
1201        escaped = f" ESCAPED BY {escaped}" if escaped else ""
1202        items = expression.args.get("collection_items")
1203        items = f" COLLECTION ITEMS TERMINATED BY {items}" if items else ""
1204        keys = expression.args.get("map_keys")
1205        keys = f" MAP KEYS TERMINATED BY {keys}" if keys else ""
1206        lines = expression.args.get("lines")
1207        lines = f" LINES TERMINATED BY {lines}" if lines else ""
1208        null = expression.args.get("null")
1209        null = f" NULL DEFINED AS {null}" if null else ""
1210        return f"ROW FORMAT DELIMITED{fields}{escaped}{items}{keys}{lines}{null}"
1211
1212    def withtablehint_sql(self, expression: exp.WithTableHint) -> str:
1213        return f"WITH ({self.expressions(expression, flat=True)})"
1214
1215    def indextablehint_sql(self, expression: exp.IndexTableHint) -> str:
1216        this = f"{self.sql(expression, 'this')} INDEX"
1217        target = self.sql(expression, "target")
1218        target = f" FOR {target}" if target else ""
1219        return f"{this}{target} ({self.expressions(expression, flat=True)})"
1220
1221    def table_sql(self, expression: exp.Table, sep: str = " AS ") -> str:
1222        table = ".".join(
1223            part
1224            for part in [
1225                self.sql(expression, "catalog"),
1226                self.sql(expression, "db"),
1227                self.sql(expression, "this"),
1228            ]
1229            if part
1230        )
1231
1232        alias = self.sql(expression, "alias")
1233        alias = f"{sep}{alias}" if alias else ""
1234        hints = self.expressions(expression, key="hints", sep=" ")
1235        hints = f" {hints}" if hints and self.TABLE_HINTS else ""
1236        pivots = self.expressions(expression, key="pivots", sep=" ", flat=True)
1237        pivots = f" {pivots}" if pivots else ""
1238        joins = self.expressions(expression, key="joins", sep="", skip_first=True)
1239        laterals = self.expressions(expression, key="laterals", sep="")
1240        system_time = expression.args.get("system_time")
1241        system_time = f" {self.sql(expression, 'system_time')}" if system_time else ""
1242
1243        return f"{table}{system_time}{alias}{hints}{pivots}{joins}{laterals}"
1244
1245    def tablesample_sql(
1246        self, expression: exp.TableSample, seed_prefix: str = "SEED", sep=" AS "
1247    ) -> str:
1248        if self.ALIAS_POST_TABLESAMPLE and expression.this.alias:
1249            table = expression.this.copy()
1250            table.set("alias", None)
1251            this = self.sql(table)
1252            alias = f"{sep}{self.sql(expression.this, 'alias')}"
1253        else:
1254            this = self.sql(expression, "this")
1255            alias = ""
1256        method = self.sql(expression, "method")
1257        method = f"{method.upper()} " if method and self.TABLESAMPLE_WITH_METHOD else ""
1258        numerator = self.sql(expression, "bucket_numerator")
1259        denominator = self.sql(expression, "bucket_denominator")
1260        field = self.sql(expression, "bucket_field")
1261        field = f" ON {field}" if field else ""
1262        bucket = f"BUCKET {numerator} OUT OF {denominator}{field}" if numerator else ""
1263        percent = self.sql(expression, "percent")
1264        percent = f"{percent} PERCENT" if percent else ""
1265        rows = self.sql(expression, "rows")
1266        rows = f"{rows} ROWS" if rows else ""
1267        size = self.sql(expression, "size")
1268        if size and self.TABLESAMPLE_SIZE_IS_PERCENT:
1269            size = f"{size} PERCENT"
1270        seed = self.sql(expression, "seed")
1271        seed = f" {seed_prefix} ({seed})" if seed else ""
1272        kind = expression.args.get("kind", "TABLESAMPLE")
1273        return f"{this} {kind} {method}({bucket}{percent}{rows}{size}){seed}{alias}"
1274
1275    def pivot_sql(self, expression: exp.Pivot) -> str:
1276        expressions = self.expressions(expression, flat=True)
1277
1278        if expression.this:
1279            this = self.sql(expression, "this")
1280            on = f"{self.seg('ON')} {expressions}"
1281            using = self.expressions(expression, key="using", flat=True)
1282            using = f"{self.seg('USING')} {using}" if using else ""
1283            group = self.sql(expression, "group")
1284            return f"PIVOT {this}{on}{using}{group}"
1285
1286        alias = self.sql(expression, "alias")
1287        alias = f" AS {alias}" if alias else ""
1288        unpivot = expression.args.get("unpivot")
1289        direction = "UNPIVOT" if unpivot else "PIVOT"
1290        field = self.sql(expression, "field")
1291        return f"{direction}({expressions} FOR {field}){alias}"
1292
1293    def tuple_sql(self, expression: exp.Tuple) -> str:
1294        return f"({self.expressions(expression, flat=True)})"
1295
1296    def update_sql(self, expression: exp.Update) -> str:
1297        this = self.sql(expression, "this")
1298        set_sql = self.expressions(expression, flat=True)
1299        from_sql = self.sql(expression, "from")
1300        where_sql = self.sql(expression, "where")
1301        returning = self.sql(expression, "returning")
1302        limit = self.sql(expression, "limit")
1303        if self.RETURNING_END:
1304            expression_sql = f"{from_sql}{where_sql}{returning}{limit}"
1305        else:
1306            expression_sql = f"{returning}{from_sql}{where_sql}{limit}"
1307        sql = f"UPDATE {this} SET {set_sql}{expression_sql}"
1308        return self.prepend_ctes(expression, sql)
1309
1310    def values_sql(self, expression: exp.Values) -> str:
1311        # The VALUES clause is still valid in an `INSERT INTO ..` statement, for example
1312        if self.VALUES_AS_TABLE or not expression.find_ancestor(exp.From, exp.Join):
1313            args = self.expressions(expression)
1314            alias = self.sql(expression, "alias")
1315            values = f"VALUES{self.seg('')}{args}"
1316            values = (
1317                f"({values})"
1318                if self.WRAP_DERIVED_VALUES and (alias or isinstance(expression.parent, exp.From))
1319                else values
1320            )
1321            return f"{values} AS {alias}" if alias else values
1322
1323        # Converts `VALUES...` expression into a series of select unions.
1324        # Note: If you have a lot of unions then this will result in a large number of recursive statements to
1325        # evaluate the expression. You may need to increase `sys.setrecursionlimit` to run and it can also be
1326        # very slow.
1327        expression = expression.copy()
1328        column_names = expression.alias and expression.args["alias"].columns
1329
1330        selects = []
1331
1332        for i, tup in enumerate(expression.expressions):
1333            row = tup.expressions
1334
1335            if i == 0 and column_names:
1336                row = [
1337                    exp.alias_(value, column_name) for value, column_name in zip(row, column_names)
1338                ]
1339
1340            selects.append(exp.Select(expressions=row))
1341
1342        subquery_expression: exp.Select | exp.Union = selects[0]
1343        if len(selects) > 1:
1344            for select in selects[1:]:
1345                subquery_expression = exp.union(
1346                    subquery_expression, select, distinct=False, copy=False
1347                )
1348
1349        return self.subquery_sql(subquery_expression.subquery(expression.alias, copy=False))
1350
1351    def var_sql(self, expression: exp.Var) -> str:
1352        return self.sql(expression, "this")
1353
1354    def into_sql(self, expression: exp.Into) -> str:
1355        temporary = " TEMPORARY" if expression.args.get("temporary") else ""
1356        unlogged = " UNLOGGED" if expression.args.get("unlogged") else ""
1357        return f"{self.seg('INTO')}{temporary or unlogged} {self.sql(expression, 'this')}"
1358
1359    def from_sql(self, expression: exp.From) -> str:
1360        return f"{self.seg('FROM')} {self.sql(expression, 'this')}"
1361
1362    def group_sql(self, expression: exp.Group) -> str:
1363        group_by = self.op_expressions("GROUP BY", expression)
1364
1365        if expression.args.get("all"):
1366            return f"{group_by} ALL"
1367
1368        grouping_sets = self.expressions(expression, key="grouping_sets", indent=False)
1369        grouping_sets = (
1370            f"{self.seg('GROUPING SETS')} {self.wrap(grouping_sets)}" if grouping_sets else ""
1371        )
1372
1373        cube = expression.args.get("cube", [])
1374        if seq_get(cube, 0) is True:
1375            return f"{group_by}{self.seg('WITH CUBE')}"
1376        else:
1377            cube_sql = self.expressions(expression, key="cube", indent=False)
1378            cube_sql = f"{self.seg('CUBE')} {self.wrap(cube_sql)}" if cube_sql else ""
1379
1380        rollup = expression.args.get("rollup", [])
1381        if seq_get(rollup, 0) is True:
1382            return f"{group_by}{self.seg('WITH ROLLUP')}"
1383        else:
1384            rollup_sql = self.expressions(expression, key="rollup", indent=False)
1385            rollup_sql = f"{self.seg('ROLLUP')} {self.wrap(rollup_sql)}" if rollup_sql else ""
1386
1387        groupings = csv(
1388            grouping_sets,
1389            cube_sql,
1390            rollup_sql,
1391            self.seg("WITH TOTALS") if expression.args.get("totals") else "",
1392            sep=self.GROUPINGS_SEP,
1393        )
1394
1395        if expression.args.get("expressions") and groupings:
1396            group_by = f"{group_by}{self.GROUPINGS_SEP}"
1397
1398        return f"{group_by}{groupings}"
1399
1400    def having_sql(self, expression: exp.Having) -> str:
1401        this = self.indent(self.sql(expression, "this"))
1402        return f"{self.seg('HAVING')}{self.sep()}{this}"
1403
1404    def join_sql(self, expression: exp.Join) -> str:
1405        op_sql = " ".join(
1406            op
1407            for op in (
1408                expression.method,
1409                "GLOBAL" if expression.args.get("global") else None,
1410                expression.side,
1411                expression.kind,
1412                expression.hint if self.JOIN_HINTS else None,
1413            )
1414            if op
1415        )
1416        on_sql = self.sql(expression, "on")
1417        using = expression.args.get("using")
1418
1419        if not on_sql and using:
1420            on_sql = csv(*(self.sql(column) for column in using))
1421
1422        this_sql = self.sql(expression, "this")
1423
1424        if on_sql:
1425            on_sql = self.indent(on_sql, skip_first=True)
1426            space = self.seg(" " * self.pad) if self.pretty else " "
1427            if using:
1428                on_sql = f"{space}USING ({on_sql})"
1429            else:
1430                on_sql = f"{space}ON {on_sql}"
1431        elif not op_sql:
1432            return f", {this_sql}"
1433
1434        op_sql = f"{op_sql} JOIN" if op_sql else "JOIN"
1435        return f"{self.seg(op_sql)} {this_sql}{on_sql}"
1436
1437    def lambda_sql(self, expression: exp.Lambda, arrow_sep: str = "->") -> str:
1438        args = self.expressions(expression, flat=True)
1439        args = f"({args})" if len(args.split(",")) > 1 else args
1440        return f"{args} {arrow_sep} {self.sql(expression, 'this')}"
1441
1442    def lateral_sql(self, expression: exp.Lateral) -> str:
1443        this = self.sql(expression, "this")
1444
1445        if isinstance(expression.this, exp.Subquery):
1446            return f"LATERAL {this}"
1447
1448        if expression.args.get("view"):
1449            alias = expression.args["alias"]
1450            columns = self.expressions(alias, key="columns", flat=True)
1451            table = f" {alias.name}" if alias.name else ""
1452            columns = f" AS {columns}" if columns else ""
1453            op_sql = self.seg(f"LATERAL VIEW{' OUTER' if expression.args.get('outer') else ''}")
1454            return f"{op_sql}{self.sep()}{this}{table}{columns}"
1455
1456        alias = self.sql(expression, "alias")
1457        alias = f" AS {alias}" if alias else ""
1458        return f"LATERAL {this}{alias}"
1459
1460    def limit_sql(self, expression: exp.Limit, top: bool = False) -> str:
1461        this = self.sql(expression, "this")
1462        args = ", ".join(
1463            sql
1464            for sql in (
1465                self.sql(expression, "offset"),
1466                self.sql(expression, "expression"),
1467            )
1468            if sql
1469        )
1470        return f"{this}{self.seg('TOP' if top else 'LIMIT')} {args}"
1471
1472    def offset_sql(self, expression: exp.Offset) -> str:
1473        this = self.sql(expression, "this")
1474        return f"{this}{self.seg('OFFSET')} {self.sql(expression, 'expression')}"
1475
1476    def setitem_sql(self, expression: exp.SetItem) -> str:
1477        kind = self.sql(expression, "kind")
1478        kind = f"{kind} " if kind else ""
1479        this = self.sql(expression, "this")
1480        expressions = self.expressions(expression)
1481        collate = self.sql(expression, "collate")
1482        collate = f" COLLATE {collate}" if collate else ""
1483        global_ = "GLOBAL " if expression.args.get("global") else ""
1484        return f"{global_}{kind}{this}{expressions}{collate}"
1485
1486    def set_sql(self, expression: exp.Set) -> str:
1487        expressions = (
1488            f" {self.expressions(expression, flat=True)}" if expression.expressions else ""
1489        )
1490        tag = " TAG" if expression.args.get("tag") else ""
1491        return f"{'UNSET' if expression.args.get('unset') else 'SET'}{tag}{expressions}"
1492
1493    def pragma_sql(self, expression: exp.Pragma) -> str:
1494        return f"PRAGMA {self.sql(expression, 'this')}"
1495
1496    def lock_sql(self, expression: exp.Lock) -> str:
1497        if not self.LOCKING_READS_SUPPORTED:
1498            self.unsupported("Locking reads using 'FOR UPDATE/SHARE' are not supported")
1499            return ""
1500
1501        lock_type = "FOR UPDATE" if expression.args["update"] else "FOR SHARE"
1502        expressions = self.expressions(expression, flat=True)
1503        expressions = f" OF {expressions}" if expressions else ""
1504        wait = expression.args.get("wait")
1505
1506        if wait is not None:
1507            if isinstance(wait, exp.Literal):
1508                wait = f" WAIT {self.sql(wait)}"
1509            else:
1510                wait = " NOWAIT" if wait else " SKIP LOCKED"
1511
1512        return f"{lock_type}{expressions}{wait or ''}"
1513
1514    def literal_sql(self, expression: exp.Literal) -> str:
1515        text = expression.this or ""
1516        if expression.is_string:
1517            text = f"{self.QUOTE_START}{self.escape_str(text)}{self.QUOTE_END}"
1518        return text
1519
1520    def escape_str(self, text: str) -> str:
1521        text = text.replace(self.QUOTE_END, self._escaped_quote_end)
1522        if self.ESCAPE_LINE_BREAK:
1523            text = text.replace("\n", "\\n")
1524        elif self.pretty:
1525            text = text.replace("\n", self.SENTINEL_LINE_BREAK)
1526        return text
1527
1528    def loaddata_sql(self, expression: exp.LoadData) -> str:
1529        local = " LOCAL" if expression.args.get("local") else ""
1530        inpath = f" INPATH {self.sql(expression, 'inpath')}"
1531        overwrite = " OVERWRITE" if expression.args.get("overwrite") else ""
1532        this = f" INTO TABLE {self.sql(expression, 'this')}"
1533        partition = self.sql(expression, "partition")
1534        partition = f" {partition}" if partition else ""
1535        input_format = self.sql(expression, "input_format")
1536        input_format = f" INPUTFORMAT {input_format}" if input_format else ""
1537        serde = self.sql(expression, "serde")
1538        serde = f" SERDE {serde}" if serde else ""
1539        return f"LOAD DATA{local}{inpath}{overwrite}{this}{partition}{input_format}{serde}"
1540
1541    def null_sql(self, *_) -> str:
1542        return "NULL"
1543
1544    def boolean_sql(self, expression: exp.Boolean) -> str:
1545        return "TRUE" if expression.this else "FALSE"
1546
1547    def order_sql(self, expression: exp.Order, flat: bool = False) -> str:
1548        this = self.sql(expression, "this")
1549        this = f"{this} " if this else this
1550        return self.op_expressions(f"{this}ORDER BY", expression, flat=this or flat)  # type: ignore
1551
1552    def cluster_sql(self, expression: exp.Cluster) -> str:
1553        return self.op_expressions("CLUSTER BY", expression)
1554
1555    def distribute_sql(self, expression: exp.Distribute) -> str:
1556        return self.op_expressions("DISTRIBUTE BY", expression)
1557
1558    def sort_sql(self, expression: exp.Sort) -> str:
1559        return self.op_expressions("SORT BY", expression)
1560
1561    def ordered_sql(self, expression: exp.Ordered) -> str:
1562        desc = expression.args.get("desc")
1563        asc = not desc
1564
1565        nulls_first = expression.args.get("nulls_first")
1566        nulls_last = not nulls_first
1567        nulls_are_large = self.NULL_ORDERING == "nulls_are_large"
1568        nulls_are_small = self.NULL_ORDERING == "nulls_are_small"
1569        nulls_are_last = self.NULL_ORDERING == "nulls_are_last"
1570
1571        sort_order = " DESC" if desc else ""
1572        nulls_sort_change = ""
1573        if nulls_first and (
1574            (asc and nulls_are_large) or (desc and nulls_are_small) or nulls_are_last
1575        ):
1576            nulls_sort_change = " NULLS FIRST"
1577        elif (
1578            nulls_last
1579            and ((asc and nulls_are_small) or (desc and nulls_are_large))
1580            and not nulls_are_last
1581        ):
1582            nulls_sort_change = " NULLS LAST"
1583
1584        if nulls_sort_change and not self.NULL_ORDERING_SUPPORTED:
1585            self.unsupported(
1586                "Sorting in an ORDER BY on NULLS FIRST/NULLS LAST is not supported by this dialect"
1587            )
1588            nulls_sort_change = ""
1589
1590        return f"{self.sql(expression, 'this')}{sort_order}{nulls_sort_change}"
1591
1592    def matchrecognize_sql(self, expression: exp.MatchRecognize) -> str:
1593        partition = self.partition_by_sql(expression)
1594        order = self.sql(expression, "order")
1595        measures = self.expressions(expression, key="measures")
1596        measures = self.seg(f"MEASURES{self.seg(measures)}") if measures else ""
1597        rows = self.sql(expression, "rows")
1598        rows = self.seg(rows) if rows else ""
1599        after = self.sql(expression, "after")
1600        after = self.seg(after) if after else ""
1601        pattern = self.sql(expression, "pattern")
1602        pattern = self.seg(f"PATTERN ({pattern})") if pattern else ""
1603        definition_sqls = [
1604            f"{self.sql(definition, 'alias')} AS {self.sql(definition, 'this')}"
1605            for definition in expression.args.get("define", [])
1606        ]
1607        definitions = self.expressions(sqls=definition_sqls)
1608        define = self.seg(f"DEFINE{self.seg(definitions)}") if definitions else ""
1609        body = "".join(
1610            (
1611                partition,
1612                order,
1613                measures,
1614                rows,
1615                after,
1616                pattern,
1617                define,
1618            )
1619        )
1620        alias = self.sql(expression, "alias")
1621        alias = f" {alias}" if alias else ""
1622        return f"{self.seg('MATCH_RECOGNIZE')} {self.wrap(body)}{alias}"
1623
1624    def query_modifiers(self, expression: exp.Expression, *sqls: str) -> str:
1625        limit: t.Optional[exp.Fetch | exp.Limit] = expression.args.get("limit")
1626
1627        # If the limit is generated as TOP, we need to ensure it's not generated twice
1628        with_offset_limit_modifiers = not isinstance(limit, exp.Limit) or not self.LIMIT_IS_TOP
1629
1630        if self.LIMIT_FETCH == "LIMIT" and isinstance(limit, exp.Fetch):
1631            limit = exp.Limit(expression=exp.maybe_copy(limit.args.get("count")))
1632        elif self.LIMIT_FETCH == "FETCH" and isinstance(limit, exp.Limit):
1633            limit = exp.Fetch(direction="FIRST", count=exp.maybe_copy(limit.expression))
1634
1635        fetch = isinstance(limit, exp.Fetch)
1636
1637        offset_limit_modifiers = (
1638            self.offset_limit_modifiers(expression, fetch, limit)
1639            if with_offset_limit_modifiers
1640            else []
1641        )
1642
1643        return csv(
1644            *sqls,
1645            *[self.sql(join) for join in expression.args.get("joins") or []],
1646            self.sql(expression, "match"),
1647            *[self.sql(lateral) for lateral in expression.args.get("laterals") or []],
1648            self.sql(expression, "where"),
1649            self.sql(expression, "group"),
1650            self.sql(expression, "having"),
1651            *self.after_having_modifiers(expression),
1652            self.sql(expression, "order"),
1653            *offset_limit_modifiers,
1654            *self.after_limit_modifiers(expression),
1655            sep="",
1656        )
1657
1658    def offset_limit_modifiers(
1659        self, expression: exp.Expression, fetch: bool, limit: t.Optional[exp.Fetch | exp.Limit]
1660    ) -> t.List[str]:
1661        return [
1662            self.sql(expression, "offset") if fetch else self.sql(limit),
1663            self.sql(limit) if fetch else self.sql(expression, "offset"),
1664        ]
1665
1666    def after_having_modifiers(self, expression: exp.Expression) -> t.List[str]:
1667        return [
1668            self.sql(expression, "qualify"),
1669            self.seg("WINDOW ") + self.expressions(expression, key="windows", flat=True)
1670            if expression.args.get("windows")
1671            else "",
1672            self.sql(expression, "distribute"),
1673            self.sql(expression, "sort"),
1674            self.sql(expression, "cluster"),
1675        ]
1676
1677    def after_limit_modifiers(self, expression: exp.Expression) -> t.List[str]:
1678        locks = self.expressions(expression, key="locks", sep=" ")
1679        locks = f" {locks}" if locks else ""
1680        return [locks, self.sql(expression, "sample")]
1681
1682    def select_sql(self, expression: exp.Select) -> str:
1683        hint = self.sql(expression, "hint")
1684        distinct = self.sql(expression, "distinct")
1685        distinct = f" {distinct}" if distinct else ""
1686        kind = self.sql(expression, "kind").upper()
1687        limit = expression.args.get("limit")
1688        top = (
1689            self.limit_sql(limit, top=True)
1690            if isinstance(limit, exp.Limit) and self.LIMIT_IS_TOP
1691            else ""
1692        )
1693
1694        expressions = self.expressions(expression)
1695
1696        if kind:
1697            if kind in self.SELECT_KINDS:
1698                kind = f" AS {kind}"
1699            else:
1700                if kind == "STRUCT":
1701                    expressions = self.expressions(
1702                        sqls=[
1703                            self.sql(
1704                                exp.Struct(
1705                                    expressions=[
1706                                        exp.column(e.output_name).eq(
1707                                            e.this if isinstance(e, exp.Alias) else e
1708                                        )
1709                                        for e in expression.expressions
1710                                    ]
1711                                )
1712                            )
1713                        ]
1714                    )
1715                kind = ""
1716
1717        expressions = f"{self.sep()}{expressions}" if expressions else expressions
1718        sql = self.query_modifiers(
1719            expression,
1720            f"SELECT{top}{hint}{distinct}{kind}{expressions}",
1721            self.sql(expression, "into", comment=False),
1722            self.sql(expression, "from", comment=False),
1723        )
1724        return self.prepend_ctes(expression, sql)
1725
1726    def schema_sql(self, expression: exp.Schema) -> str:
1727        this = self.sql(expression, "this")
1728        this = f"{this} " if this else ""
1729        sql = self.schema_columns_sql(expression)
1730        return f"{this}{sql}"
1731
1732    def schema_columns_sql(self, expression: exp.Schema) -> str:
1733        return f"({self.sep('')}{self.expressions(expression)}{self.seg(')', sep='')}"
1734
1735    def star_sql(self, expression: exp.Star) -> str:
1736        except_ = self.expressions(expression, key="except", flat=True)
1737        except_ = f"{self.seg(self.STAR_MAPPING['except'])} ({except_})" if except_ else ""
1738        replace = self.expressions(expression, key="replace", flat=True)
1739        replace = f"{self.seg(self.STAR_MAPPING['replace'])} ({replace})" if replace else ""
1740        return f"*{except_}{replace}"
1741
1742    def parameter_sql(self, expression: exp.Parameter) -> str:
1743        this = self.sql(expression, "this")
1744        this = f"{{{this}}}" if expression.args.get("wrapped") else f"{this}"
1745        return f"{self.PARAMETER_TOKEN}{this}"
1746
1747    def sessionparameter_sql(self, expression: exp.SessionParameter) -> str:
1748        this = self.sql(expression, "this")
1749        kind = expression.text("kind")
1750        if kind:
1751            kind = f"{kind}."
1752        return f"@@{kind}{this}"
1753
1754    def placeholder_sql(self, expression: exp.Placeholder) -> str:
1755        return f":{expression.name}" if expression.name else "?"
1756
1757    def subquery_sql(self, expression: exp.Subquery, sep: str = " AS ") -> str:
1758        alias = self.sql(expression, "alias")
1759        alias = f"{sep}{alias}" if alias else ""
1760
1761        pivots = self.expressions(expression, key="pivots", sep=" ", flat=True)
1762        pivots = f" {pivots}" if pivots else ""
1763
1764        sql = self.query_modifiers(expression, self.wrap(expression), alias, pivots)
1765        return self.prepend_ctes(expression, sql)
1766
1767    def qualify_sql(self, expression: exp.Qualify) -> str:
1768        this = self.indent(self.sql(expression, "this"))
1769        return f"{self.seg('QUALIFY')}{self.sep()}{this}"
1770
1771    def union_sql(self, expression: exp.Union) -> str:
1772        return self.prepend_ctes(
1773            expression,
1774            self.set_operation(expression, self.union_op(expression)),
1775        )
1776
1777    def union_op(self, expression: exp.Union) -> str:
1778        kind = " DISTINCT" if self.EXPLICIT_UNION else ""
1779        kind = kind if expression.args.get("distinct") else " ALL"
1780        return f"UNION{kind}"
1781
1782    def unnest_sql(self, expression: exp.Unnest) -> str:
1783        args = self.expressions(expression, flat=True)
1784        alias = expression.args.get("alias")
1785        if alias and self.UNNEST_COLUMN_ONLY:
1786            columns = alias.columns
1787            alias = self.sql(columns[0]) if columns else ""
1788        else:
1789            alias = self.sql(expression, "alias")
1790        alias = f" AS {alias}" if alias else alias
1791        ordinality = " WITH ORDINALITY" if expression.args.get("ordinality") else ""
1792        offset = expression.args.get("offset")
1793        offset = f" WITH OFFSET AS {self.sql(offset)}" if offset else ""
1794        return f"UNNEST({args}){ordinality}{alias}{offset}"
1795
1796    def where_sql(self, expression: exp.Where) -> str:
1797        this = self.indent(self.sql(expression, "this"))
1798        return f"{self.seg('WHERE')}{self.sep()}{this}"
1799
1800    def window_sql(self, expression: exp.Window) -> str:
1801        this = self.sql(expression, "this")
1802        partition = self.partition_by_sql(expression)
1803        order = expression.args.get("order")
1804        order = self.order_sql(order, flat=True) if order else ""
1805        spec = self.sql(expression, "spec")
1806        alias = self.sql(expression, "alias")
1807        over = self.sql(expression, "over") or "OVER"
1808
1809        this = f"{this} {'AS' if expression.arg_key == 'windows' else over}"
1810
1811        first = expression.args.get("first")
1812        if first is None:
1813            first = ""
1814        else:
1815            first = "FIRST" if first else "LAST"
1816
1817        if not partition and not order and not spec and alias:
1818            return f"{this} {alias}"
1819
1820        args = " ".join(arg for arg in (alias, first, partition, order, spec) if arg)
1821        return f"{this} ({args})"
1822
1823    def partition_by_sql(self, expression: exp.Window | exp.MatchRecognize) -> str:
1824        partition = self.expressions(expression, key="partition_by", flat=True)
1825        return f"PARTITION BY {partition}" if partition else ""
1826
1827    def windowspec_sql(self, expression: exp.WindowSpec) -> str:
1828        kind = self.sql(expression, "kind")
1829        start = csv(self.sql(expression, "start"), self.sql(expression, "start_side"), sep=" ")
1830        end = (
1831            csv(self.sql(expression, "end"), self.sql(expression, "end_side"), sep=" ")
1832            or "CURRENT ROW"
1833        )
1834        return f"{kind} BETWEEN {start} AND {end}"
1835
1836    def withingroup_sql(self, expression: exp.WithinGroup) -> str:
1837        this = self.sql(expression, "this")
1838        expression_sql = self.sql(expression, "expression")[1:]  # order has a leading space
1839        return f"{this} WITHIN GROUP ({expression_sql})"
1840
1841    def between_sql(self, expression: exp.Between) -> str:
1842        this = self.sql(expression, "this")
1843        low = self.sql(expression, "low")
1844        high = self.sql(expression, "high")
1845        return f"{this} BETWEEN {low} AND {high}"
1846
1847    def bracket_sql(self, expression: exp.Bracket) -> str:
1848        expressions = apply_index_offset(expression.this, expression.expressions, self.INDEX_OFFSET)
1849        expressions_sql = ", ".join(self.sql(e) for e in expressions)
1850
1851        return f"{self.sql(expression, 'this')}[{expressions_sql}]"
1852
1853    def safebracket_sql(self, expression: exp.SafeBracket) -> str:
1854        return self.bracket_sql(expression)
1855
1856    def all_sql(self, expression: exp.All) -> str:
1857        return f"ALL {self.wrap(expression)}"
1858
1859    def any_sql(self, expression: exp.Any) -> str:
1860        this = self.sql(expression, "this")
1861        if isinstance(expression.this, exp.Subqueryable):
1862            this = self.wrap(this)
1863        return f"ANY {this}"
1864
1865    def exists_sql(self, expression: exp.Exists) -> str:
1866        return f"EXISTS{self.wrap(expression)}"
1867
1868    def case_sql(self, expression: exp.Case) -> str:
1869        this = self.sql(expression, "this")
1870        statements = [f"CASE {this}" if this else "CASE"]
1871
1872        for e in expression.args["ifs"]:
1873            statements.append(f"WHEN {self.sql(e, 'this')}")
1874            statements.append(f"THEN {self.sql(e, 'true')}")
1875
1876        default = self.sql(expression, "default")
1877
1878        if default:
1879            statements.append(f"ELSE {default}")
1880
1881        statements.append("END")
1882
1883        if self.pretty and self.text_width(statements) > self.max_text_width:
1884            return self.indent("\n".join(statements), skip_first=True, skip_last=True)
1885
1886        return " ".join(statements)
1887
1888    def constraint_sql(self, expression: exp.Constraint) -> str:
1889        this = self.sql(expression, "this")
1890        expressions = self.expressions(expression, flat=True)
1891        return f"CONSTRAINT {this} {expressions}"
1892
1893    def nextvaluefor_sql(self, expression: exp.NextValueFor) -> str:
1894        order = expression.args.get("order")
1895        order = f" OVER ({self.order_sql(order, flat=True)})" if order else ""
1896        return f"NEXT VALUE FOR {self.sql(expression, 'this')}{order}"
1897
1898    def extract_sql(self, expression: exp.Extract) -> str:
1899        this = self.sql(expression, "this") if self.EXTRACT_ALLOWS_QUOTES else expression.this.name
1900        expression_sql = self.sql(expression, "expression")
1901        return f"EXTRACT({this} FROM {expression_sql})"
1902
1903    def trim_sql(self, expression: exp.Trim) -> str:
1904        trim_type = self.sql(expression, "position")
1905
1906        if trim_type == "LEADING":
1907            return self.func("LTRIM", expression.this)
1908        elif trim_type == "TRAILING":
1909            return self.func("RTRIM", expression.this)
1910        else:
1911            return self.func("TRIM", expression.this, expression.expression)
1912
1913    def safeconcat_sql(self, expression: exp.SafeConcat) -> str:
1914        expressions = expression.expressions
1915        if self.STRICT_STRING_CONCAT:
1916            expressions = (exp.cast(e, "text") for e in expressions)
1917        return self.func("CONCAT", *expressions)
1918
1919    def check_sql(self, expression: exp.Check) -> str:
1920        this = self.sql(expression, key="this")
1921        return f"CHECK ({this})"
1922
1923    def foreignkey_sql(self, expression: exp.ForeignKey) -> str:
1924        expressions = self.expressions(expression, flat=True)
1925        reference = self.sql(expression, "reference")
1926        reference = f" {reference}" if reference else ""
1927        delete = self.sql(expression, "delete")
1928        delete = f" ON DELETE {delete}" if delete else ""
1929        update = self.sql(expression, "update")
1930        update = f" ON UPDATE {update}" if update else ""
1931        return f"FOREIGN KEY ({expressions}){reference}{delete}{update}"
1932
1933    def primarykey_sql(self, expression: exp.ForeignKey) -> str:
1934        expressions = self.expressions(expression, flat=True)
1935        options = self.expressions(expression, key="options", flat=True, sep=" ")
1936        options = f" {options}" if options else ""
1937        return f"PRIMARY KEY ({expressions}){options}"
1938
1939    def if_sql(self, expression: exp.If) -> str:
1940        expression = expression.copy()
1941        return self.case_sql(exp.Case(ifs=[expression], default=expression.args.get("false")))
1942
1943    def matchagainst_sql(self, expression: exp.MatchAgainst) -> str:
1944        modifier = expression.args.get("modifier")
1945        modifier = f" {modifier}" if modifier else ""
1946        return f"{self.func('MATCH', *expression.expressions)} AGAINST({self.sql(expression, 'this')}{modifier})"
1947
1948    def jsonkeyvalue_sql(self, expression: exp.JSONKeyValue) -> str:
1949        return f"{self.sql(expression, 'this')}: {self.sql(expression, 'expression')}"
1950
1951    def jsonobject_sql(self, expression: exp.JSONObject) -> str:
1952        null_handling = expression.args.get("null_handling")
1953        null_handling = f" {null_handling}" if null_handling else ""
1954        unique_keys = expression.args.get("unique_keys")
1955        if unique_keys is not None:
1956            unique_keys = f" {'WITH' if unique_keys else 'WITHOUT'} UNIQUE KEYS"
1957        else:
1958            unique_keys = ""
1959        return_type = self.sql(expression, "return_type")
1960        return_type = f" RETURNING {return_type}" if return_type else ""
1961        format_json = " FORMAT JSON" if expression.args.get("format_json") else ""
1962        encoding = self.sql(expression, "encoding")
1963        encoding = f" ENCODING {encoding}" if encoding else ""
1964        return self.func(
1965            "JSON_OBJECT",
1966            *expression.expressions,
1967            suffix=f"{null_handling}{unique_keys}{return_type}{format_json}{encoding})",
1968        )
1969
1970    def openjsoncolumndef_sql(self, expression: exp.OpenJSONColumnDef) -> str:
1971        this = self.sql(expression, "this")
1972        kind = self.sql(expression, "kind")
1973        path = self.sql(expression, "path")
1974        path = f" {path}" if path else ""
1975        as_json = " AS JSON" if expression.args.get("as_json") else ""
1976        return f"{this} {kind}{path}{as_json}"
1977
1978    def openjson_sql(self, expression: exp.OpenJSON) -> str:
1979        this = self.sql(expression, "this")
1980        path = self.sql(expression, "path")
1981        path = f", {path}" if path else ""
1982        expressions = self.expressions(expression)
1983        with_ = (
1984            f" WITH ({self.seg(self.indent(expressions), sep='')}{self.seg(')', sep='')}"
1985            if expressions
1986            else ""
1987        )
1988        return f"OPENJSON({this}{path}){with_}"
1989
1990    def in_sql(self, expression: exp.In) -> str:
1991        query = expression.args.get("query")
1992        unnest = expression.args.get("unnest")
1993        field = expression.args.get("field")
1994        is_global = " GLOBAL" if expression.args.get("is_global") else ""
1995
1996        if query:
1997            in_sql = self.wrap(query)
1998        elif unnest:
1999            in_sql = self.in_unnest_op(unnest)
2000        elif field:
2001            in_sql = self.sql(field)
2002        else:
2003            in_sql = f"({self.expressions(expression, flat=True)})"
2004
2005        return f"{self.sql(expression, 'this')}{is_global} IN {in_sql}"
2006
2007    def in_unnest_op(self, unnest: exp.Unnest) -> str:
2008        return f"(SELECT {self.sql(unnest)})"
2009
2010    def interval_sql(self, expression: exp.Interval) -> str:
2011        unit = self.sql(expression, "unit")
2012        if not self.INTERVAL_ALLOWS_PLURAL_FORM:
2013            unit = self.TIME_PART_SINGULARS.get(unit.lower(), unit)
2014        unit = f" {unit}" if unit else ""
2015
2016        if self.SINGLE_STRING_INTERVAL:
2017            this = expression.this.name if expression.this else ""
2018            return f"INTERVAL '{this}{unit}'" if this else f"INTERVAL{unit}"
2019
2020        this = self.sql(expression, "this")
2021        if this:
2022            unwrapped = isinstance(expression.this, self.UNWRAPPED_INTERVAL_VALUES)
2023            this = f" {this}" if unwrapped else f" ({this})"
2024
2025        return f"INTERVAL{this}{unit}"
2026
2027    def return_sql(self, expression: exp.Return) -> str:
2028        return f"RETURN {self.sql(expression, 'this')}"
2029
2030    def reference_sql(self, expression: exp.Reference) -> str:
2031        this = self.sql(expression, "this")
2032        expressions = self.expressions(expression, flat=True)
2033        expressions = f"({expressions})" if expressions else ""
2034        options = self.expressions(expression, key="options", flat=True, sep=" ")
2035        options = f" {options}" if options else ""
2036        return f"REFERENCES {this}{expressions}{options}"
2037
2038    def anonymous_sql(self, expression: exp.Anonymous) -> str:
2039        return self.func(expression.name, *expression.expressions)
2040
2041    def paren_sql(self, expression: exp.Paren) -> str:
2042        if isinstance(expression.unnest(), exp.Select):
2043            sql = self.wrap(expression)
2044        else:
2045            sql = self.seg(self.indent(self.sql(expression, "this")), sep="")
2046            sql = f"({sql}{self.seg(')', sep='')}"
2047
2048        return self.prepend_ctes(expression, sql)
2049
2050    def neg_sql(self, expression: exp.Neg) -> str:
2051        # This makes sure we don't convert "- - 5" to "--5", which is a comment
2052        this_sql = self.sql(expression, "this")
2053        sep = " " if this_sql[0] == "-" else ""
2054        return f"-{sep}{this_sql}"
2055
2056    def not_sql(self, expression: exp.Not) -> str:
2057        return f"NOT {self.sql(expression, 'this')}"
2058
2059    def alias_sql(self, expression: exp.Alias) -> str:
2060        alias = self.sql(expression, "alias")
2061        alias = f" AS {alias}" if alias else ""
2062        return f"{self.sql(expression, 'this')}{alias}"
2063
2064    def aliases_sql(self, expression: exp.Aliases) -> str:
2065        return f"{self.sql(expression, 'this')} AS ({self.expressions(expression, flat=True)})"
2066
2067    def attimezone_sql(self, expression: exp.AtTimeZone) -> str:
2068        this = self.sql(expression, "this")
2069        zone = self.sql(expression, "zone")
2070        return f"{this} AT TIME ZONE {zone}"
2071
2072    def add_sql(self, expression: exp.Add) -> str:
2073        return self.binary(expression, "+")
2074
2075    def and_sql(self, expression: exp.And) -> str:
2076        return self.connector_sql(expression, "AND")
2077
2078    def xor_sql(self, expression: exp.Xor) -> str:
2079        return self.connector_sql(expression, "XOR")
2080
2081    def connector_sql(self, expression: exp.Connector, op: str) -> str:
2082        if not self.pretty:
2083            return self.binary(expression, op)
2084
2085        sqls = tuple(
2086            self.maybe_comment(self.sql(e), e, e.parent.comments or []) if i != 1 else self.sql(e)
2087            for i, e in enumerate(expression.flatten(unnest=False))
2088        )
2089
2090        sep = "\n" if self.text_width(sqls) > self.max_text_width else " "
2091        return f"{sep}{op} ".join(sqls)
2092
2093    def bitwiseand_sql(self, expression: exp.BitwiseAnd) -> str:
2094        return self.binary(expression, "&")
2095
2096    def bitwiseleftshift_sql(self, expression: exp.BitwiseLeftShift) -> str:
2097        return self.binary(expression, "<<")
2098
2099    def bitwisenot_sql(self, expression: exp.BitwiseNot) -> str:
2100        return f"~{self.sql(expression, 'this')}"
2101
2102    def bitwiseor_sql(self, expression: exp.BitwiseOr) -> str:
2103        return self.binary(expression, "|")
2104
2105    def bitwiserightshift_sql(self, expression: exp.BitwiseRightShift) -> str:
2106        return self.binary(expression, ">>")
2107
2108    def bitwisexor_sql(self, expression: exp.BitwiseXor) -> str:
2109        return self.binary(expression, "^")
2110
2111    def cast_sql(self, expression: exp.Cast, safe_prefix: t.Optional[str] = None) -> str:
2112        format_sql = self.sql(expression, "format")
2113        format_sql = f" FORMAT {format_sql}" if format_sql else ""
2114        return f"{safe_prefix or ''}CAST({self.sql(expression, 'this')} AS {self.sql(expression, 'to')}{format_sql})"
2115
2116    def currentdate_sql(self, expression: exp.CurrentDate) -> str:
2117        zone = self.sql(expression, "this")
2118        return f"CURRENT_DATE({zone})" if zone else "CURRENT_DATE"
2119
2120    def collate_sql(self, expression: exp.Collate) -> str:
2121        return self.binary(expression, "COLLATE")
2122
2123    def command_sql(self, expression: exp.Command) -> str:
2124        return f"{self.sql(expression, 'this').upper()} {expression.text('expression').strip()}"
2125
2126    def comment_sql(self, expression: exp.Comment) -> str:
2127        this = self.sql(expression, "this")
2128        kind = expression.args["kind"]
2129        exists_sql = " IF EXISTS " if expression.args.get("exists") else " "
2130        expression_sql = self.sql(expression, "expression")
2131        return f"COMMENT{exists_sql}ON {kind} {this} IS {expression_sql}"
2132
2133    def mergetreettlaction_sql(self, expression: exp.MergeTreeTTLAction) -> str:
2134        this = self.sql(expression, "this")
2135        delete = " DELETE" if expression.args.get("delete") else ""
2136        recompress = self.sql(expression, "recompress")
2137        recompress = f" RECOMPRESS {recompress}" if recompress else ""
2138        to_disk = self.sql(expression, "to_disk")
2139        to_disk = f" TO DISK {to_disk}" if to_disk else ""
2140        to_volume = self.sql(expression, "to_volume")
2141        to_volume = f" TO VOLUME {to_volume}" if to_volume else ""
2142        return f"{this}{delete}{recompress}{to_disk}{to_volume}"
2143
2144    def mergetreettl_sql(self, expression: exp.MergeTreeTTL) -> str:
2145        where = self.sql(expression, "where")
2146        group = self.sql(expression, "group")
2147        aggregates = self.expressions(expression, key="aggregates")
2148        aggregates = self.seg("SET") + self.seg(aggregates) if aggregates else ""
2149
2150        if not (where or group or aggregates) and len(expression.expressions) == 1:
2151            return f"TTL {self.expressions(expression, flat=True)}"
2152
2153        return f"TTL{self.seg(self.expressions(expression))}{where}{group}{aggregates}"
2154
2155    def transaction_sql(self, expression: exp.Transaction) -> str:
2156        return "BEGIN"
2157
2158    def commit_sql(self, expression: exp.Commit) -> str:
2159        chain = expression.args.get("chain")
2160        if chain is not None:
2161            chain = " AND CHAIN" if chain else " AND NO CHAIN"
2162
2163        return f"COMMIT{chain or ''}"
2164
2165    def rollback_sql(self, expression: exp.Rollback) -> str:
2166        savepoint = expression.args.get("savepoint")
2167        savepoint = f" TO {savepoint}" if savepoint else ""
2168        return f"ROLLBACK{savepoint}"
2169
2170    def altercolumn_sql(self, expression: exp.AlterColumn) -> str:
2171        this = self.sql(expression, "this")
2172
2173        dtype = self.sql(expression, "dtype")
2174        if dtype:
2175            collate = self.sql(expression, "collate")
2176            collate = f" COLLATE {collate}" if collate else ""
2177            using = self.sql(expression, "using")
2178            using = f" USING {using}" if using else ""
2179            return f"ALTER COLUMN {this} TYPE {dtype}{collate}{using}"
2180
2181        default = self.sql(expression, "default")
2182        if default:
2183            return f"ALTER COLUMN {this} SET DEFAULT {default}"
2184
2185        if not expression.args.get("drop"):
2186            self.unsupported("Unsupported ALTER COLUMN syntax")
2187
2188        return f"ALTER COLUMN {this} DROP DEFAULT"
2189
2190    def renametable_sql(self, expression: exp.RenameTable) -> str:
2191        if not self.RENAME_TABLE_WITH_DB:
2192            # Remove db from tables
2193            expression = expression.transform(
2194                lambda n: exp.table_(n.this) if isinstance(n, exp.Table) else n
2195            )
2196        this = self.sql(expression, "this")
2197        return f"RENAME TO {this}"
2198
2199    def altertable_sql(self, expression: exp.AlterTable) -> str:
2200        actions = expression.args["actions"]
2201
2202        if isinstance(actions[0], exp.ColumnDef):
2203            actions = self.expressions(expression, key="actions", prefix="ADD COLUMN ")
2204        elif isinstance(actions[0], exp.Schema):
2205            actions = self.expressions(expression, key="actions", prefix="ADD COLUMNS ")
2206        elif isinstance(actions[0], exp.Delete):
2207            actions = self.expressions(expression, key="actions", flat=True)
2208        else:
2209            actions = self.expressions(expression, key="actions")
2210
2211        exists = " IF EXISTS" if expression.args.get("exists") else ""
2212        return f"ALTER TABLE{exists} {self.sql(expression, 'this')} {actions}"
2213
2214    def droppartition_sql(self, expression: exp.DropPartition) -> str:
2215        expressions = self.expressions(expression)
2216        exists = " IF EXISTS " if expression.args.get("exists") else " "
2217        return f"DROP{exists}{expressions}"
2218
2219    def addconstraint_sql(self, expression: exp.AddConstraint) -> str:
2220        this = self.sql(expression, "this")
2221        expression_ = self.sql(expression, "expression")
2222        add_constraint = f"ADD CONSTRAINT {this}" if this else "ADD"
2223
2224        enforced = expression.args.get("enforced")
2225        if enforced is not None:
2226            return f"{add_constraint} CHECK ({expression_}){' ENFORCED' if enforced else ''}"
2227
2228        return f"{add_constraint} {expression_}"
2229
2230    def distinct_sql(self, expression: exp.Distinct) -> str:
2231        this = self.expressions(expression, flat=True)
2232        this = f" {this}" if this else ""
2233
2234        on = self.sql(expression, "on")
2235        on = f" ON {on}" if on else ""
2236        return f"DISTINCT{this}{on}"
2237
2238    def ignorenulls_sql(self, expression: exp.IgnoreNulls) -> str:
2239        return f"{self.sql(expression, 'this')} IGNORE NULLS"
2240
2241    def respectnulls_sql(self, expression: exp.RespectNulls) -> str:
2242        return f"{self.sql(expression, 'this')} RESPECT NULLS"
2243
2244    def intdiv_sql(self, expression: exp.IntDiv) -> str:
2245        return self.sql(
2246            exp.Cast(
2247                this=exp.Div(this=expression.this.copy(), expression=expression.expression.copy()),
2248                to=exp.DataType(this=exp.DataType.Type.INT),
2249            )
2250        )
2251
2252    def dpipe_sql(self, expression: exp.DPipe) -> str:
2253        return self.binary(expression, "||")
2254
2255    def safedpipe_sql(self, expression: exp.SafeDPipe) -> str:
2256        if self.STRICT_STRING_CONCAT:
2257            return self.func("CONCAT", *(exp.cast(e, "text") for e in expression.flatten()))
2258        return self.dpipe_sql(expression)
2259
2260    def div_sql(self, expression: exp.Div) -> str:
2261        return self.binary(expression, "/")
2262
2263    def overlaps_sql(self, expression: exp.Overlaps) -> str:
2264        return self.binary(expression, "OVERLAPS")
2265
2266    def distance_sql(self, expression: exp.Distance) -> str:
2267        return self.binary(expression, "<->")
2268
2269    def dot_sql(self, expression: exp.Dot) -> str:
2270        return f"{self.sql(expression, 'this')}.{self.sql(expression, 'expression')}"
2271
2272    def eq_sql(self, expression: exp.EQ) -> str:
2273        return self.binary(expression, "=")
2274
2275    def escape_sql(self, expression: exp.Escape) -> str:
2276        return self.binary(expression, "ESCAPE")
2277
2278    def glob_sql(self, expression: exp.Glob) -> str:
2279        return self.binary(expression, "GLOB")
2280
2281    def gt_sql(self, expression: exp.GT) -> str:
2282        return self.binary(expression, ">")
2283
2284    def gte_sql(self, expression: exp.GTE) -> str:
2285        return self.binary(expression, ">=")
2286
2287    def ilike_sql(self, expression: exp.ILike) -> str:
2288        return self.binary(expression, "ILIKE")
2289
2290    def ilikeany_sql(self, expression: exp.ILikeAny) -> str:
2291        return self.binary(expression, "ILIKE ANY")
2292
2293    def is_sql(self, expression: exp.Is) -> str:
2294        if not self.IS_BOOL_ALLOWED and isinstance(expression.expression, exp.Boolean):
2295            return self.sql(
2296                expression.this if expression.expression.this else exp.not_(expression.this)
2297            )
2298        return self.binary(expression, "IS")
2299
2300    def like_sql(self, expression: exp.Like) -> str:
2301        return self.binary(expression, "LIKE")
2302
2303    def likeany_sql(self, expression: exp.LikeAny) -> str:
2304        return self.binary(expression, "LIKE ANY")
2305
2306    def similarto_sql(self, expression: exp.SimilarTo) -> str:
2307        return self.binary(expression, "SIMILAR TO")
2308
2309    def lt_sql(self, expression: exp.LT) -> str:
2310        return self.binary(expression, "<")
2311
2312    def lte_sql(self, expression: exp.LTE) -> str:
2313        return self.binary(expression, "<=")
2314
2315    def mod_sql(self, expression: exp.Mod) -> str:
2316        return self.binary(expression, "%")
2317
2318    def mul_sql(self, expression: exp.Mul) -> str:
2319        return self.binary(expression, "*")
2320
2321    def neq_sql(self, expression: exp.NEQ) -> str:
2322        return self.binary(expression, "<>")
2323
2324    def nullsafeeq_sql(self, expression: exp.NullSafeEQ) -> str:
2325        return self.binary(expression, "IS NOT DISTINCT FROM")
2326
2327    def nullsafeneq_sql(self, expression: exp.NullSafeNEQ) -> str:
2328        return self.binary(expression, "IS DISTINCT FROM")
2329
2330    def or_sql(self, expression: exp.Or) -> str:
2331        return self.connector_sql(expression, "OR")
2332
2333    def slice_sql(self, expression: exp.Slice) -> str:
2334        return self.binary(expression, ":")
2335
2336    def sub_sql(self, expression: exp.Sub) -> str:
2337        return self.binary(expression, "-")
2338
2339    def trycast_sql(self, expression: exp.TryCast) -> str:
2340        return self.cast_sql(expression, safe_prefix="TRY_")
2341
2342    def use_sql(self, expression: exp.Use) -> str:
2343        kind = self.sql(expression, "kind")
2344        kind = f" {kind}" if kind else ""
2345        this = self.sql(expression, "this")
2346        this = f" {this}" if this else ""
2347        return f"USE{kind}{this}"
2348
2349    def binary(self, expression: exp.Binary, op: str) -> str:
2350        op = self.maybe_comment(op, comments=expression.comments)
2351        return f"{self.sql(expression, 'this')} {op} {self.sql(expression, 'expression')}"
2352
2353    def function_fallback_sql(self, expression: exp.Func) -> str:
2354        args = []
2355
2356        for key in expression.arg_types:
2357            arg_value = expression.args.get(key)
2358
2359            if isinstance(arg_value, list):
2360                for value in arg_value:
2361                    args.append(value)
2362            elif arg_value is not None:
2363                args.append(arg_value)
2364
2365        if self.normalize_functions:
2366            name = expression.sql_name()
2367        else:
2368            name = (expression._meta and expression.meta.get("name")) or expression.sql_name()
2369
2370        return self.func(name, *args)
2371
2372    def func(
2373        self,
2374        name: str,
2375        *args: t.Optional[exp.Expression | str],
2376        prefix: str = "(",
2377        suffix: str = ")",
2378    ) -> str:
2379        return f"{self.normalize_func(name)}{prefix}{self.format_args(*args)}{suffix}"
2380
2381    def format_args(self, *args: t.Optional[str | exp.Expression]) -> str:
2382        arg_sqls = tuple(self.sql(arg) for arg in args if arg is not None)
2383        if self.pretty and self.text_width(arg_sqls) > self.max_text_width:
2384            return self.indent("\n" + f",\n".join(arg_sqls) + "\n", skip_first=True, skip_last=True)
2385        return ", ".join(arg_sqls)
2386
2387    def text_width(self, args: t.Iterable) -> int:
2388        return sum(len(arg) for arg in args)
2389
2390    def format_time(self, expression: exp.Expression) -> t.Optional[str]:
2391        return format_time(
2392            self.sql(expression, "format"), self.INVERSE_TIME_MAPPING, self.INVERSE_TIME_TRIE
2393        )
2394
2395    def expressions(
2396        self,
2397        expression: t.Optional[exp.Expression] = None,
2398        key: t.Optional[str] = None,
2399        sqls: t.Optional[t.List[str]] = None,
2400        flat: bool = False,
2401        indent: bool = True,
2402        skip_first: bool = False,
2403        sep: str = ", ",
2404        prefix: str = "",
2405    ) -> str:
2406        expressions = expression.args.get(key or "expressions") if expression else sqls
2407
2408        if not expressions:
2409            return ""
2410
2411        if flat:
2412            return sep.join(sql for sql in (self.sql(e) for e in expressions) if sql)
2413
2414        num_sqls = len(expressions)
2415
2416        # These are calculated once in case we have the leading_comma / pretty option set, correspondingly
2417        pad = " " * self.pad
2418        stripped_sep = sep.strip()
2419
2420        result_sqls = []
2421        for i, e in enumerate(expressions):
2422            sql = self.sql(e, comment=False)
2423            if not sql:
2424                continue
2425
2426            comments = self.maybe_comment("", e) if isinstance(e, exp.Expression) else ""
2427
2428            if self.pretty:
2429                if self.leading_comma:
2430                    result_sqls.append(f"{sep if i > 0 else pad}{prefix}{sql}{comments}")
2431                else:
2432                    result_sqls.append(
2433                        f"{prefix}{sql}{stripped_sep if i + 1 < num_sqls else ''}{comments}"
2434                    )
2435            else:
2436                result_sqls.append(f"{prefix}{sql}{comments}{sep if i + 1 < num_sqls else ''}")
2437
2438        result_sql = "\n".join(result_sqls) if self.pretty else "".join(result_sqls)
2439        return self.indent(result_sql, skip_first=skip_first) if indent else result_sql
2440
2441    def op_expressions(self, op: str, expression: exp.Expression, flat: bool = False) -> str:
2442        flat = flat or isinstance(expression.parent, exp.Properties)
2443        expressions_sql = self.expressions(expression, flat=flat)
2444        if flat:
2445            return f"{op} {expressions_sql}"
2446        return f"{self.seg(op)}{self.sep() if expressions_sql else ''}{expressions_sql}"
2447
2448    def naked_property(self, expression: exp.Property) -> str:
2449        property_name = exp.Properties.PROPERTY_TO_NAME.get(expression.__class__)
2450        if not property_name:
2451            self.unsupported(f"Unsupported property {expression.__class__.__name__}")
2452        return f"{property_name} {self.sql(expression, 'this')}"
2453
2454    def set_operation(self, expression: exp.Expression, op: str) -> str:
2455        this = self.sql(expression, "this")
2456        op = self.seg(op)
2457        return self.query_modifiers(
2458            expression, f"{this}{op}{self.sep()}{self.sql(expression, 'expression')}"
2459        )
2460
2461    def tag_sql(self, expression: exp.Tag) -> str:
2462        return f"{expression.args.get('prefix')}{self.sql(expression.this)}{expression.args.get('postfix')}"
2463
2464    def token_sql(self, token_type: TokenType) -> str:
2465        return self.TOKEN_MAPPING.get(token_type, token_type.name)
2466
2467    def userdefinedfunction_sql(self, expression: exp.UserDefinedFunction) -> str:
2468        this = self.sql(expression, "this")
2469        expressions = self.no_identify(self.expressions, expression)
2470        expressions = (
2471            self.wrap(expressions) if expression.args.get("wrapped") else f" {expressions}"
2472        )
2473        return f"{this}{expressions}"
2474
2475    def joinhint_sql(self, expression: exp.JoinHint) -> str:
2476        this = self.sql(expression, "this")
2477        expressions = self.expressions(expression, flat=True)
2478        return f"{this}({expressions})"
2479
2480    def kwarg_sql(self, expression: exp.Kwarg) -> str:
2481        return self.binary(expression, "=>")
2482
2483    def when_sql(self, expression: exp.When) -> str:
2484        matched = "MATCHED" if expression.args["matched"] else "NOT MATCHED"
2485        source = " BY SOURCE" if self.MATCHED_BY_SOURCE and expression.args.get("source") else ""
2486        condition = self.sql(expression, "condition")
2487        condition = f" AND {condition}" if condition else ""
2488
2489        then_expression = expression.args.get("then")
2490        if isinstance(then_expression, exp.Insert):
2491            then = f"INSERT {self.sql(then_expression, 'this')}"
2492            if "expression" in then_expression.args:
2493                then += f" VALUES {self.sql(then_expression, 'expression')}"
2494        elif isinstance(then_expression, exp.Update):
2495            if isinstance(then_expression.args.get("expressions"), exp.Star):
2496                then = f"UPDATE {self.sql(then_expression, 'expressions')}"
2497            else:
2498                then = f"UPDATE SET {self.expressions(then_expression, flat=True)}"
2499        else:
2500            then = self.sql(then_expression)
2501        return f"WHEN {matched}{source}{condition} THEN {then}"
2502
2503    def merge_sql(self, expression: exp.Merge) -> str:
2504        this = self.sql(expression, "this")
2505        using = f"USING {self.sql(expression, 'using')}"
2506        on = f"ON {self.sql(expression, 'on')}"
2507        return f"MERGE INTO {this} {using} {on} {self.expressions(expression, sep=' ')}"
2508
2509    def tochar_sql(self, expression: exp.ToChar) -> str:
2510        if expression.args.get("format"):
2511            self.unsupported("Format argument unsupported for TO_CHAR/TO_VARCHAR function")
2512
2513        return self.sql(exp.cast(expression.this, "text"))
2514
2515    def dictproperty_sql(self, expression: exp.DictProperty) -> str:
2516        this = self.sql(expression, "this")
2517        kind = self.sql(expression, "kind")
2518        settings_sql = self.expressions(expression, key="settings", sep=" ")
2519        args = f"({self.sep('')}{settings_sql}{self.seg(')', sep='')}" if settings_sql else "()"
2520        return f"{this}({kind}{args})"
2521
2522    def dictrange_sql(self, expression: exp.DictRange) -> str:
2523        this = self.sql(expression, "this")
2524        max = self.sql(expression, "max")
2525        min = self.sql(expression, "min")
2526        return f"{this}(MIN {min} MAX {max})"
2527
2528    def dictsubproperty_sql(self, expression: exp.DictSubProperty) -> str:
2529        return f"{self.sql(expression, 'this')} {self.sql(expression, 'value')}"
2530
2531    def oncluster_sql(self, expression: exp.OnCluster) -> str:
2532        return ""
2533
2534    def clusteredbyproperty_sql(self, expression: exp.ClusteredByProperty) -> str:
2535        expressions = self.expressions(expression, key="expressions", flat=True)
2536        sorted_by = self.expressions(expression, key="sorted_by", flat=True)
2537        sorted_by = f" SORTED BY ({sorted_by})" if sorted_by else ""
2538        buckets = self.sql(expression, "buckets")
2539        return f"CLUSTERED BY ({expressions}){sorted_by} INTO {buckets} BUCKETS"
2540
2541    def anyvalue_sql(self, expression: exp.AnyValue) -> str:
2542        this = self.sql(expression, "this")
2543        having = self.sql(expression, "having")
2544
2545        if having:
2546            this = f"{this} HAVING {'MAX' if expression.args.get('max') else 'MIN'} {having}"
2547
2548        return self.func("ANY_VALUE", this)
2549
2550    def querytransform_sql(self, expression: exp.QueryTransform) -> str:
2551        transform = self.func("TRANSFORM", *expression.expressions)
2552        row_format_before = self.sql(expression, "row_format_before")
2553        row_format_before = f" {row_format_before}" if row_format_before else ""
2554        record_writer = self.sql(expression, "record_writer")
2555        record_writer = f" RECORDWRITER {record_writer}" if record_writer else ""
2556        using = f" USING {self.sql(expression, 'command_script')}"
2557        schema = self.sql(expression, "schema")
2558        schema = f" AS {schema}" if schema else ""
2559        row_format_after = self.sql(expression, "row_format_after")
2560        row_format_after = f" {row_format_after}" if row_format_after else ""
2561        record_reader = self.sql(expression, "record_reader")
2562        record_reader = f" RECORDREADER {record_reader}" if record_reader else ""
2563        return f"{transform}{row_format_before}{record_writer}{using}{schema}{row_format_after}{record_reader}"
2564
2565    def indexconstraintoption_sql(self, expression: exp.IndexConstraintOption) -> str:
2566        key_block_size = self.sql(expression, "key_block_size")
2567        if key_block_size:
2568            return f"KEY_BLOCK_SIZE = {key_block_size}"
2569
2570        using = self.sql(expression, "using")
2571        if using:
2572            return f"USING {using}"
2573
2574        parser = self.sql(expression, "parser")
2575        if parser:
2576            return f"WITH PARSER {parser}"
2577
2578        comment = self.sql(expression, "comment")
2579        if comment:
2580            return f"COMMENT {comment}"
2581
2582        visible = expression.args.get("visible")
2583        if visible is not None:
2584            return "VISIBLE" if visible else "INVISIBLE"
2585
2586        engine_attr = self.sql(expression, "engine_attr")
2587        if engine_attr:
2588            return f"ENGINE_ATTRIBUTE = {engine_attr}"
2589
2590        secondary_engine_attr = self.sql(expression, "secondary_engine_attr")
2591        if secondary_engine_attr:
2592            return f"SECONDARY_ENGINE_ATTRIBUTE = {secondary_engine_attr}"
2593
2594        self.unsupported("Unsupported index constraint option.")
2595        return ""
2596
2597    def indexcolumnconstraint_sql(self, expression: exp.IndexColumnConstraint) -> str:
2598        kind = self.sql(expression, "kind")
2599        kind = f"{kind} INDEX" if kind else "INDEX"
2600        this = self.sql(expression, "this")
2601        this = f" {this}" if this else ""
2602        type_ = self.sql(expression, "type")
2603        type_ = f" USING {type_}" if type_ else ""
2604        schema = self.sql(expression, "schema")
2605        schema = f" {schema}" if schema else ""
2606        options = self.expressions(expression, key="options", sep=" ")
2607        options = f" {options}" if options else ""
2608        return f"{kind}{this}{type_}{schema}{options}"
2609
2610
2611def cached_generator(
2612    cache: t.Optional[t.Dict[int, str]] = None
2613) -> t.Callable[[exp.Expression], str]:
2614    """Returns a cached generator."""
2615    cache = {} if cache is None else cache
2616    generator = Generator(normalize=True, identify="safe")
2617    return lambda e: generator.generate(e, cache)