sqlglot.dialects.dialect

  1from __future__ import annotations
  2
  3import typing as t
  4from enum import Enum
  5from functools import reduce
  6
  7from sqlglot import exp
  8from sqlglot._typing import E
  9from sqlglot.errors import ParseError
 10from sqlglot.generator import Generator
 11from sqlglot.helper import flatten, seq_get
 12from sqlglot.parser import Parser
 13from sqlglot.time import format_time
 14from sqlglot.tokens import Token, Tokenizer, TokenType
 15from sqlglot.trie import new_trie
 16
 17B = t.TypeVar("B", bound=exp.Binary)
 18
 19
 20class Dialects(str, Enum):
 21    DIALECT = ""
 22
 23    BIGQUERY = "bigquery"
 24    CLICKHOUSE = "clickhouse"
 25    DATABRICKS = "databricks"
 26    DRILL = "drill"
 27    DUCKDB = "duckdb"
 28    HIVE = "hive"
 29    MYSQL = "mysql"
 30    ORACLE = "oracle"
 31    POSTGRES = "postgres"
 32    PRESTO = "presto"
 33    REDSHIFT = "redshift"
 34    SNOWFLAKE = "snowflake"
 35    SPARK = "spark"
 36    SPARK2 = "spark2"
 37    SQLITE = "sqlite"
 38    STARROCKS = "starrocks"
 39    TABLEAU = "tableau"
 40    TERADATA = "teradata"
 41    TRINO = "trino"
 42    TSQL = "tsql"
 43    Doris = "doris"
 44
 45
 46class _Dialect(type):
 47    classes: t.Dict[str, t.Type[Dialect]] = {}
 48
 49    def __eq__(cls, other: t.Any) -> bool:
 50        if cls is other:
 51            return True
 52        if isinstance(other, str):
 53            return cls is cls.get(other)
 54        if isinstance(other, Dialect):
 55            return cls is type(other)
 56
 57        return False
 58
 59    def __hash__(cls) -> int:
 60        return hash(cls.__name__.lower())
 61
 62    @classmethod
 63    def __getitem__(cls, key: str) -> t.Type[Dialect]:
 64        return cls.classes[key]
 65
 66    @classmethod
 67    def get(
 68        cls, key: str, default: t.Optional[t.Type[Dialect]] = None
 69    ) -> t.Optional[t.Type[Dialect]]:
 70        return cls.classes.get(key, default)
 71
 72    def __new__(cls, clsname, bases, attrs):
 73        klass = super().__new__(cls, clsname, bases, attrs)
 74        enum = Dialects.__members__.get(clsname.upper())
 75        cls.classes[enum.value if enum is not None else clsname.lower()] = klass
 76
 77        klass.TIME_TRIE = new_trie(klass.TIME_MAPPING)
 78        klass.FORMAT_TRIE = (
 79            new_trie(klass.FORMAT_MAPPING) if klass.FORMAT_MAPPING else klass.TIME_TRIE
 80        )
 81        klass.INVERSE_TIME_MAPPING = {v: k for k, v in klass.TIME_MAPPING.items()}
 82        klass.INVERSE_TIME_TRIE = new_trie(klass.INVERSE_TIME_MAPPING)
 83
 84        klass.tokenizer_class = getattr(klass, "Tokenizer", Tokenizer)
 85        klass.parser_class = getattr(klass, "Parser", Parser)
 86        klass.generator_class = getattr(klass, "Generator", Generator)
 87
 88        klass.QUOTE_START, klass.QUOTE_END = list(klass.tokenizer_class._QUOTES.items())[0]
 89        klass.IDENTIFIER_START, klass.IDENTIFIER_END = list(
 90            klass.tokenizer_class._IDENTIFIERS.items()
 91        )[0]
 92
 93        def get_start_end(token_type: TokenType) -> t.Tuple[t.Optional[str], t.Optional[str]]:
 94            return next(
 95                (
 96                    (s, e)
 97                    for s, (e, t) in klass.tokenizer_class._FORMAT_STRINGS.items()
 98                    if t == token_type
 99                ),
100                (None, None),
101            )
102
103        klass.BIT_START, klass.BIT_END = get_start_end(TokenType.BIT_STRING)
104        klass.HEX_START, klass.HEX_END = get_start_end(TokenType.HEX_STRING)
105        klass.BYTE_START, klass.BYTE_END = get_start_end(TokenType.BYTE_STRING)
106
107        dialect_properties = {
108            **{
109                k: v
110                for k, v in vars(klass).items()
111                if not callable(v) and not isinstance(v, classmethod) and not k.startswith("__")
112            },
113            "TOKENIZER_CLASS": klass.tokenizer_class,
114        }
115
116        if enum not in ("", "bigquery"):
117            dialect_properties["SELECT_KINDS"] = ()
118
119        # Pass required dialect properties to the tokenizer, parser and generator classes
120        for subclass in (klass.tokenizer_class, klass.parser_class, klass.generator_class):
121            for name, value in dialect_properties.items():
122                if hasattr(subclass, name):
123                    setattr(subclass, name, value)
124
125        if not klass.STRICT_STRING_CONCAT and klass.DPIPE_IS_STRING_CONCAT:
126            klass.parser_class.BITWISE[TokenType.DPIPE] = exp.SafeDPipe
127
128        klass.generator_class.can_identify = klass.can_identify
129
130        return klass
131
132
133class Dialect(metaclass=_Dialect):
134    # Determines the base index offset for arrays
135    INDEX_OFFSET = 0
136
137    # If true unnest table aliases are considered only as column aliases
138    UNNEST_COLUMN_ONLY = False
139
140    # Determines whether or not the table alias comes after tablesample
141    ALIAS_POST_TABLESAMPLE = False
142
143    # Determines whether or not unquoted identifiers are resolved as uppercase
144    # When set to None, it means that the dialect treats all identifiers as case-insensitive
145    RESOLVES_IDENTIFIERS_AS_UPPERCASE: t.Optional[bool] = False
146
147    # Determines whether or not an unquoted identifier can start with a digit
148    IDENTIFIERS_CAN_START_WITH_DIGIT = False
149
150    # Determines whether or not the DPIPE token ('||') is a string concatenation operator
151    DPIPE_IS_STRING_CONCAT = True
152
153    # Determines whether or not CONCAT's arguments must be strings
154    STRICT_STRING_CONCAT = False
155
156    # Determines how function names are going to be normalized
157    NORMALIZE_FUNCTIONS: bool | str = "upper"
158
159    # Indicates the default null ordering method to use if not explicitly set
160    # Options are: "nulls_are_small", "nulls_are_large", "nulls_are_last"
161    NULL_ORDERING = "nulls_are_small"
162
163    DATE_FORMAT = "'%Y-%m-%d'"
164    DATEINT_FORMAT = "'%Y%m%d'"
165    TIME_FORMAT = "'%Y-%m-%d %H:%M:%S'"
166
167    # Custom time mappings in which the key represents dialect time format
168    # and the value represents a python time format
169    TIME_MAPPING: t.Dict[str, str] = {}
170
171    # https://cloud.google.com/bigquery/docs/reference/standard-sql/format-elements#format_model_rules_date_time
172    # https://docs.teradata.com/r/Teradata-Database-SQL-Functions-Operators-Expressions-and-Predicates/March-2017/Data-Type-Conversions/Character-to-DATE-Conversion/Forcing-a-FORMAT-on-CAST-for-Converting-Character-to-DATE
173    # special syntax cast(x as date format 'yyyy') defaults to time_mapping
174    FORMAT_MAPPING: t.Dict[str, str] = {}
175
176    # Columns that are auto-generated by the engine corresponding to this dialect
177    # Such columns may be excluded from SELECT * queries, for example
178    PSEUDOCOLUMNS: t.Set[str] = set()
179
180    # Autofilled
181    tokenizer_class = Tokenizer
182    parser_class = Parser
183    generator_class = Generator
184
185    # A trie of the time_mapping keys
186    TIME_TRIE: t.Dict = {}
187    FORMAT_TRIE: t.Dict = {}
188
189    INVERSE_TIME_MAPPING: t.Dict[str, str] = {}
190    INVERSE_TIME_TRIE: t.Dict = {}
191
192    def __eq__(self, other: t.Any) -> bool:
193        return type(self) == other
194
195    def __hash__(self) -> int:
196        return hash(type(self))
197
198    @classmethod
199    def get_or_raise(cls, dialect: DialectType) -> t.Type[Dialect]:
200        if not dialect:
201            return cls
202        if isinstance(dialect, _Dialect):
203            return dialect
204        if isinstance(dialect, Dialect):
205            return dialect.__class__
206
207        result = cls.get(dialect)
208        if not result:
209            raise ValueError(f"Unknown dialect '{dialect}'")
210
211        return result
212
213    @classmethod
214    def format_time(
215        cls, expression: t.Optional[str | exp.Expression]
216    ) -> t.Optional[exp.Expression]:
217        if isinstance(expression, str):
218            return exp.Literal.string(
219                # the time formats are quoted
220                format_time(expression[1:-1], cls.TIME_MAPPING, cls.TIME_TRIE)
221            )
222
223        if expression and expression.is_string:
224            return exp.Literal.string(format_time(expression.this, cls.TIME_MAPPING, cls.TIME_TRIE))
225
226        return expression
227
228    @classmethod
229    def normalize_identifier(cls, expression: E) -> E:
230        """
231        Normalizes an unquoted identifier to either lower or upper case, thus essentially
232        making it case-insensitive. If a dialect treats all identifiers as case-insensitive,
233        they will be normalized regardless of being quoted or not.
234        """
235        if isinstance(expression, exp.Identifier) and (
236            not expression.quoted or cls.RESOLVES_IDENTIFIERS_AS_UPPERCASE is None
237        ):
238            expression.set(
239                "this",
240                expression.this.upper()
241                if cls.RESOLVES_IDENTIFIERS_AS_UPPERCASE
242                else expression.this.lower(),
243            )
244
245        return expression
246
247    @classmethod
248    def case_sensitive(cls, text: str) -> bool:
249        """Checks if text contains any case sensitive characters, based on the dialect's rules."""
250        if cls.RESOLVES_IDENTIFIERS_AS_UPPERCASE is None:
251            return False
252
253        unsafe = str.islower if cls.RESOLVES_IDENTIFIERS_AS_UPPERCASE else str.isupper
254        return any(unsafe(char) for char in text)
255
256    @classmethod
257    def can_identify(cls, text: str, identify: str | bool = "safe") -> bool:
258        """Checks if text can be identified given an identify option.
259
260        Args:
261            text: The text to check.
262            identify:
263                "always" or `True`: Always returns true.
264                "safe": True if the identifier is case-insensitive.
265
266        Returns:
267            Whether or not the given text can be identified.
268        """
269        if identify is True or identify == "always":
270            return True
271
272        if identify == "safe":
273            return not cls.case_sensitive(text)
274
275        return False
276
277    @classmethod
278    def quote_identifier(cls, expression: E, identify: bool = True) -> E:
279        if isinstance(expression, exp.Identifier):
280            name = expression.this
281            expression.set(
282                "quoted",
283                identify or cls.case_sensitive(name) or not exp.SAFE_IDENTIFIER_RE.match(name),
284            )
285
286        return expression
287
288    def parse(self, sql: str, **opts) -> t.List[t.Optional[exp.Expression]]:
289        return self.parser(**opts).parse(self.tokenize(sql), sql)
290
291    def parse_into(
292        self, expression_type: exp.IntoType, sql: str, **opts
293    ) -> t.List[t.Optional[exp.Expression]]:
294        return self.parser(**opts).parse_into(expression_type, self.tokenize(sql), sql)
295
296    def generate(self, expression: t.Optional[exp.Expression], **opts) -> str:
297        return self.generator(**opts).generate(expression)
298
299    def transpile(self, sql: str, **opts) -> t.List[str]:
300        return [self.generate(expression, **opts) for expression in self.parse(sql)]
301
302    def tokenize(self, sql: str) -> t.List[Token]:
303        return self.tokenizer.tokenize(sql)
304
305    @property
306    def tokenizer(self) -> Tokenizer:
307        if not hasattr(self, "_tokenizer"):
308            self._tokenizer = self.tokenizer_class()
309        return self._tokenizer
310
311    def parser(self, **opts) -> Parser:
312        return self.parser_class(**opts)
313
314    def generator(self, **opts) -> Generator:
315        return self.generator_class(**opts)
316
317
318DialectType = t.Union[str, Dialect, t.Type[Dialect], None]
319
320
321def rename_func(name: str) -> t.Callable[[Generator, exp.Expression], str]:
322    return lambda self, expression: self.func(name, *flatten(expression.args.values()))
323
324
325def approx_count_distinct_sql(self: Generator, expression: exp.ApproxDistinct) -> str:
326    if expression.args.get("accuracy"):
327        self.unsupported("APPROX_COUNT_DISTINCT does not support accuracy")
328    return self.func("APPROX_COUNT_DISTINCT", expression.this)
329
330
331def if_sql(self: Generator, expression: exp.If) -> str:
332    return self.func(
333        "IF", expression.this, expression.args.get("true"), expression.args.get("false")
334    )
335
336
337def arrow_json_extract_sql(self: Generator, expression: exp.JSONExtract | exp.JSONBExtract) -> str:
338    return self.binary(expression, "->")
339
340
341def arrow_json_extract_scalar_sql(
342    self: Generator, expression: exp.JSONExtractScalar | exp.JSONBExtractScalar
343) -> str:
344    return self.binary(expression, "->>")
345
346
347def inline_array_sql(self: Generator, expression: exp.Array) -> str:
348    return f"[{self.expressions(expression, flat=True)}]"
349
350
351def no_ilike_sql(self: Generator, expression: exp.ILike) -> str:
352    return self.like_sql(
353        exp.Like(
354            this=exp.Lower(this=expression.this.copy()), expression=expression.expression.copy()
355        )
356    )
357
358
359def no_paren_current_date_sql(self: Generator, expression: exp.CurrentDate) -> str:
360    zone = self.sql(expression, "this")
361    return f"CURRENT_DATE AT TIME ZONE {zone}" if zone else "CURRENT_DATE"
362
363
364def no_recursive_cte_sql(self: Generator, expression: exp.With) -> str:
365    if expression.args.get("recursive"):
366        self.unsupported("Recursive CTEs are unsupported")
367        expression.args["recursive"] = False
368    return self.with_sql(expression)
369
370
371def no_safe_divide_sql(self: Generator, expression: exp.SafeDivide) -> str:
372    n = self.sql(expression, "this")
373    d = self.sql(expression, "expression")
374    return f"IF({d} <> 0, {n} / {d}, NULL)"
375
376
377def no_tablesample_sql(self: Generator, expression: exp.TableSample) -> str:
378    self.unsupported("TABLESAMPLE unsupported")
379    return self.sql(expression.this)
380
381
382def no_pivot_sql(self: Generator, expression: exp.Pivot) -> str:
383    self.unsupported("PIVOT unsupported")
384    return ""
385
386
387def no_trycast_sql(self: Generator, expression: exp.TryCast) -> str:
388    return self.cast_sql(expression)
389
390
391def no_properties_sql(self: Generator, expression: exp.Properties) -> str:
392    self.unsupported("Properties unsupported")
393    return ""
394
395
396def no_comment_column_constraint_sql(
397    self: Generator, expression: exp.CommentColumnConstraint
398) -> str:
399    self.unsupported("CommentColumnConstraint unsupported")
400    return ""
401
402
403def no_map_from_entries_sql(self: Generator, expression: exp.MapFromEntries) -> str:
404    self.unsupported("MAP_FROM_ENTRIES unsupported")
405    return ""
406
407
408def str_position_sql(self: Generator, expression: exp.StrPosition) -> str:
409    this = self.sql(expression, "this")
410    substr = self.sql(expression, "substr")
411    position = self.sql(expression, "position")
412    if position:
413        return f"STRPOS(SUBSTR({this}, {position}), {substr}) + {position} - 1"
414    return f"STRPOS({this}, {substr})"
415
416
417def struct_extract_sql(self: Generator, expression: exp.StructExtract) -> str:
418    return (
419        f"{self.sql(expression, 'this')}.{self.sql(exp.to_identifier(expression.expression.name))}"
420    )
421
422
423def var_map_sql(
424    self: Generator, expression: exp.Map | exp.VarMap, map_func_name: str = "MAP"
425) -> str:
426    keys = expression.args["keys"]
427    values = expression.args["values"]
428
429    if not isinstance(keys, exp.Array) or not isinstance(values, exp.Array):
430        self.unsupported("Cannot convert array columns into map.")
431        return self.func(map_func_name, keys, values)
432
433    args = []
434    for key, value in zip(keys.expressions, values.expressions):
435        args.append(self.sql(key))
436        args.append(self.sql(value))
437
438    return self.func(map_func_name, *args)
439
440
441def format_time_lambda(
442    exp_class: t.Type[E], dialect: str, default: t.Optional[bool | str] = None
443) -> t.Callable[[t.List], E]:
444    """Helper used for time expressions.
445
446    Args:
447        exp_class: the expression class to instantiate.
448        dialect: target sql dialect.
449        default: the default format, True being time.
450
451    Returns:
452        A callable that can be used to return the appropriately formatted time expression.
453    """
454
455    def _format_time(args: t.List):
456        return exp_class(
457            this=seq_get(args, 0),
458            format=Dialect[dialect].format_time(
459                seq_get(args, 1)
460                or (Dialect[dialect].TIME_FORMAT if default is True else default or None)
461            ),
462        )
463
464    return _format_time
465
466
467def time_format(
468    dialect: DialectType = None,
469) -> t.Callable[[Generator, exp.UnixToStr | exp.StrToUnix], t.Optional[str]]:
470    def _time_format(self: Generator, expression: exp.UnixToStr | exp.StrToUnix) -> t.Optional[str]:
471        """
472        Returns the time format for a given expression, unless it's equivalent
473        to the default time format of the dialect of interest.
474        """
475        time_format = self.format_time(expression)
476        return time_format if time_format != Dialect.get_or_raise(dialect).TIME_FORMAT else None
477
478    return _time_format
479
480
481def create_with_partitions_sql(self: Generator, expression: exp.Create) -> str:
482    """
483    In Hive and Spark, the PARTITIONED BY property acts as an extension of a table's schema. When the
484    PARTITIONED BY value is an array of column names, they are transformed into a schema. The corresponding
485    columns are removed from the create statement.
486    """
487    has_schema = isinstance(expression.this, exp.Schema)
488    is_partitionable = expression.args.get("kind") in ("TABLE", "VIEW")
489
490    if has_schema and is_partitionable:
491        expression = expression.copy()
492        prop = expression.find(exp.PartitionedByProperty)
493        if prop and prop.this and not isinstance(prop.this, exp.Schema):
494            schema = expression.this
495            columns = {v.name.upper() for v in prop.this.expressions}
496            partitions = [col for col in schema.expressions if col.name.upper() in columns]
497            schema.set("expressions", [e for e in schema.expressions if e not in partitions])
498            prop.replace(exp.PartitionedByProperty(this=exp.Schema(expressions=partitions)))
499            expression.set("this", schema)
500
501    return self.create_sql(expression)
502
503
504def parse_date_delta(
505    exp_class: t.Type[E], unit_mapping: t.Optional[t.Dict[str, str]] = None
506) -> t.Callable[[t.List], E]:
507    def inner_func(args: t.List) -> E:
508        unit_based = len(args) == 3
509        this = args[2] if unit_based else seq_get(args, 0)
510        unit = args[0] if unit_based else exp.Literal.string("DAY")
511        unit = exp.var(unit_mapping.get(unit.name.lower(), unit.name)) if unit_mapping else unit
512        return exp_class(this=this, expression=seq_get(args, 1), unit=unit)
513
514    return inner_func
515
516
517def parse_date_delta_with_interval(
518    expression_class: t.Type[E],
519) -> t.Callable[[t.List], t.Optional[E]]:
520    def func(args: t.List) -> t.Optional[E]:
521        if len(args) < 2:
522            return None
523
524        interval = args[1]
525
526        if not isinstance(interval, exp.Interval):
527            raise ParseError(f"INTERVAL expression expected but got '{interval}'")
528
529        expression = interval.this
530        if expression and expression.is_string:
531            expression = exp.Literal.number(expression.this)
532
533        return expression_class(
534            this=args[0], expression=expression, unit=exp.Literal.string(interval.text("unit"))
535        )
536
537    return func
538
539
540def date_trunc_to_time(args: t.List) -> exp.DateTrunc | exp.TimestampTrunc:
541    unit = seq_get(args, 0)
542    this = seq_get(args, 1)
543
544    if isinstance(this, exp.Cast) and this.is_type("date"):
545        return exp.DateTrunc(unit=unit, this=this)
546    return exp.TimestampTrunc(this=this, unit=unit)
547
548
549def timestamptrunc_sql(self: Generator, expression: exp.TimestampTrunc) -> str:
550    return self.func(
551        "DATE_TRUNC", exp.Literal.string(expression.text("unit") or "day"), expression.this
552    )
553
554
555def locate_to_strposition(args: t.List) -> exp.Expression:
556    return exp.StrPosition(
557        this=seq_get(args, 1), substr=seq_get(args, 0), position=seq_get(args, 2)
558    )
559
560
561def strposition_to_locate_sql(self: Generator, expression: exp.StrPosition) -> str:
562    return self.func(
563        "LOCATE", expression.args.get("substr"), expression.this, expression.args.get("position")
564    )
565
566
567def left_to_substring_sql(self: Generator, expression: exp.Left) -> str:
568    expression = expression.copy()
569    return self.sql(
570        exp.Substring(
571            this=expression.this, start=exp.Literal.number(1), length=expression.expression
572        )
573    )
574
575
576def right_to_substring_sql(self: Generator, expression: exp.Left) -> str:
577    expression = expression.copy()
578    return self.sql(
579        exp.Substring(
580            this=expression.this,
581            start=exp.Length(this=expression.this) - exp.paren(expression.expression - 1),
582        )
583    )
584
585
586def timestrtotime_sql(self: Generator, expression: exp.TimeStrToTime) -> str:
587    return self.sql(exp.cast(expression.this, "timestamp"))
588
589
590def datestrtodate_sql(self: Generator, expression: exp.DateStrToDate) -> str:
591    return self.sql(exp.cast(expression.this, "date"))
592
593
594# Used for Presto and Duckdb which use functions that don't support charset, and assume utf-8
595def encode_decode_sql(
596    self: Generator, expression: exp.Expression, name: str, replace: bool = True
597) -> str:
598    charset = expression.args.get("charset")
599    if charset and charset.name.lower() != "utf-8":
600        self.unsupported(f"Expected utf-8 character set, got {charset}.")
601
602    return self.func(name, expression.this, expression.args.get("replace") if replace else None)
603
604
605def min_or_least(self: Generator, expression: exp.Min) -> str:
606    name = "LEAST" if expression.expressions else "MIN"
607    return rename_func(name)(self, expression)
608
609
610def max_or_greatest(self: Generator, expression: exp.Max) -> str:
611    name = "GREATEST" if expression.expressions else "MAX"
612    return rename_func(name)(self, expression)
613
614
615def count_if_to_sum(self: Generator, expression: exp.CountIf) -> str:
616    cond = expression.this
617
618    if isinstance(expression.this, exp.Distinct):
619        cond = expression.this.expressions[0]
620        self.unsupported("DISTINCT is not supported when converting COUNT_IF to SUM")
621
622    return self.func("sum", exp.func("if", cond.copy(), 1, 0))
623
624
625def trim_sql(self: Generator, expression: exp.Trim) -> str:
626    target = self.sql(expression, "this")
627    trim_type = self.sql(expression, "position")
628    remove_chars = self.sql(expression, "expression")
629    collation = self.sql(expression, "collation")
630
631    # Use TRIM/LTRIM/RTRIM syntax if the expression isn't database-specific
632    if not remove_chars and not collation:
633        return self.trim_sql(expression)
634
635    trim_type = f"{trim_type} " if trim_type else ""
636    remove_chars = f"{remove_chars} " if remove_chars else ""
637    from_part = "FROM " if trim_type or remove_chars else ""
638    collation = f" COLLATE {collation}" if collation else ""
639    return f"TRIM({trim_type}{remove_chars}{from_part}{target}{collation})"
640
641
642def str_to_time_sql(self: Generator, expression: exp.Expression) -> str:
643    return self.func("STRPTIME", expression.this, self.format_time(expression))
644
645
646def ts_or_ds_to_date_sql(dialect: str) -> t.Callable:
647    def _ts_or_ds_to_date_sql(self: Generator, expression: exp.TsOrDsToDate) -> str:
648        _dialect = Dialect.get_or_raise(dialect)
649        time_format = self.format_time(expression)
650        if time_format and time_format not in (_dialect.TIME_FORMAT, _dialect.DATE_FORMAT):
651            return self.sql(exp.cast(str_to_time_sql(self, expression), "date"))
652
653        return self.sql(exp.cast(self.sql(expression, "this"), "date"))
654
655    return _ts_or_ds_to_date_sql
656
657
658def concat_to_dpipe_sql(self: Generator, expression: exp.Concat | exp.SafeConcat) -> str:
659    expression = expression.copy()
660    return self.sql(reduce(lambda x, y: exp.DPipe(this=x, expression=y), expression.expressions))
661
662
663def concat_ws_to_dpipe_sql(self: Generator, expression: exp.ConcatWs) -> str:
664    expression = expression.copy()
665    delim, *rest_args = expression.expressions
666    return self.sql(
667        reduce(
668            lambda x, y: exp.DPipe(this=x, expression=exp.DPipe(this=delim, expression=y)),
669            rest_args,
670        )
671    )
672
673
674def regexp_extract_sql(self: Generator, expression: exp.RegexpExtract) -> str:
675    bad_args = list(filter(expression.args.get, ("position", "occurrence", "parameters")))
676    if bad_args:
677        self.unsupported(f"REGEXP_EXTRACT does not support the following arg(s): {bad_args}")
678
679    return self.func(
680        "REGEXP_EXTRACT", expression.this, expression.expression, expression.args.get("group")
681    )
682
683
684def regexp_replace_sql(self: Generator, expression: exp.RegexpReplace) -> str:
685    bad_args = list(filter(expression.args.get, ("position", "occurrence", "parameters")))
686    if bad_args:
687        self.unsupported(f"REGEXP_REPLACE does not support the following arg(s): {bad_args}")
688
689    return self.func(
690        "REGEXP_REPLACE", expression.this, expression.expression, expression.args["replacement"]
691    )
692
693
694def pivot_column_names(aggregations: t.List[exp.Expression], dialect: DialectType) -> t.List[str]:
695    names = []
696    for agg in aggregations:
697        if isinstance(agg, exp.Alias):
698            names.append(agg.alias)
699        else:
700            """
701            This case corresponds to aggregations without aliases being used as suffixes
702            (e.g. col_avg(foo)). We need to unquote identifiers because they're going to
703            be quoted in the base parser's `_parse_pivot` method, due to `to_identifier`.
704            Otherwise, we'd end up with `col_avg(`foo`)` (notice the double quotes).
705            """
706            agg_all_unquoted = agg.transform(
707                lambda node: exp.Identifier(this=node.name, quoted=False)
708                if isinstance(node, exp.Identifier)
709                else node
710            )
711            names.append(agg_all_unquoted.sql(dialect=dialect, normalize_functions="lower"))
712
713    return names
714
715
716def simplify_literal(expression: E) -> E:
717    if not isinstance(expression.expression, exp.Literal):
718        from sqlglot.optimizer.simplify import simplify
719
720        simplify(expression.expression)
721
722    return expression
723
724
725def binary_from_function(expr_type: t.Type[B]) -> t.Callable[[t.List], B]:
726    return lambda args: expr_type(this=seq_get(args, 0), expression=seq_get(args, 1))
727
728
729# Used to represent DATE_TRUNC in Doris, Postgres and Starrocks dialects
730def parse_timestamp_trunc(args: t.List) -> exp.TimestampTrunc:
731    return exp.TimestampTrunc(this=seq_get(args, 1), unit=seq_get(args, 0))
732
733
734def any_value_to_max_sql(self: Generator, expression: exp.AnyValue) -> str:
735    return self.func("MAX", expression.this)
736
737
738# Used to generate JSON_OBJECT with a comma in BigQuery and MySQL instead of colon
739def json_keyvalue_comma_sql(self, expression: exp.JSONKeyValue) -> str:
740    return f"{self.sql(expression, 'this')}, {self.sql(expression, 'expression')}"