sqlglot.generator

   1from __future__ import annotations
   2
   3import logging
   4import typing as t
   5
   6from sqlglot import exp
   7from sqlglot.errors import ErrorLevel, UnsupportedError, concat_messages
   8from sqlglot.helper import apply_index_offset, csv, seq_get
   9from sqlglot.time import format_time
  10from sqlglot.tokens import TokenType
  11
  12logger = logging.getLogger("sqlglot")
  13
  14
  15class Generator:
  16    """
  17    Generator converts a given syntax tree to the corresponding SQL string.
  18
  19    Args:
  20        pretty: Whether or not to format the produced SQL string.
  21            Default: False.
  22        identify: Determines when an identifier should be quoted. Possible values are:
  23            False (default): Never quote, except in cases where it's mandatory by the dialect.
  24            True or 'always': Always quote.
  25            'safe': Only quote identifiers that are case insensitive.
  26        normalize: Whether or not to normalize identifiers to lowercase.
  27            Default: False.
  28        pad: Determines the pad size in a formatted string.
  29            Default: 2.
  30        indent: Determines the indentation size in a formatted string.
  31            Default: 2.
  32        normalize_functions: Whether or not to normalize all function names. Possible values are:
  33            "upper" or True (default): Convert names to uppercase.
  34            "lower": Convert names to lowercase.
  35            False: Disables function name normalization.
  36        unsupported_level: Determines the generator's behavior when it encounters unsupported expressions.
  37            Default ErrorLevel.WARN.
  38        max_unsupported: Maximum number of unsupported messages to include in a raised UnsupportedError.
  39            This is only relevant if unsupported_level is ErrorLevel.RAISE.
  40            Default: 3
  41        leading_comma: Determines whether or not the comma is leading or trailing in select expressions.
  42            This is only relevant when generating in pretty mode.
  43            Default: False
  44        max_text_width: The max number of characters in a segment before creating new lines in pretty mode.
  45            The default is on the smaller end because the length only represents a segment and not the true
  46            line length.
  47            Default: 80
  48        comments: Whether or not to preserve comments in the output SQL code.
  49            Default: True
  50    """
  51
  52    TRANSFORMS = {
  53        exp.DateAdd: lambda self, e: self.func(
  54            "DATE_ADD", e.this, e.expression, exp.Literal.string(e.text("unit"))
  55        ),
  56        exp.TsOrDsAdd: lambda self, e: self.func(
  57            "TS_OR_DS_ADD", e.this, e.expression, exp.Literal.string(e.text("unit"))
  58        ),
  59        exp.CaseSpecificColumnConstraint: lambda self, e: f"{'NOT ' if e.args.get('not_') else ''}CASESPECIFIC",
  60        exp.CharacterSetColumnConstraint: lambda self, e: f"CHARACTER SET {self.sql(e, 'this')}",
  61        exp.CharacterSetProperty: lambda self, e: f"{'DEFAULT ' if e.args.get('default') else ''}CHARACTER SET={self.sql(e, 'this')}",
  62        exp.CheckColumnConstraint: lambda self, e: f"CHECK ({self.sql(e, 'this')})",
  63        exp.CollateColumnConstraint: lambda self, e: f"COLLATE {self.sql(e, 'this')}",
  64        exp.CopyGrantsProperty: lambda self, e: "COPY GRANTS",
  65        exp.CommentColumnConstraint: lambda self, e: f"COMMENT {self.sql(e, 'this')}",
  66        exp.DateFormatColumnConstraint: lambda self, e: f"FORMAT {self.sql(e, 'this')}",
  67        exp.DefaultColumnConstraint: lambda self, e: f"DEFAULT {self.sql(e, 'this')}",
  68        exp.EncodeColumnConstraint: lambda self, e: f"ENCODE {self.sql(e, 'this')}",
  69        exp.ExecuteAsProperty: lambda self, e: self.naked_property(e),
  70        exp.ExternalProperty: lambda self, e: "EXTERNAL",
  71        exp.HeapProperty: lambda self, e: "HEAP",
  72        exp.InlineLengthColumnConstraint: lambda self, e: f"INLINE LENGTH {self.sql(e, 'this')}",
  73        exp.LanguageProperty: lambda self, e: self.naked_property(e),
  74        exp.LocationProperty: lambda self, e: self.naked_property(e),
  75        exp.LogProperty: lambda self, e: f"{'NO ' if e.args.get('no') else ''}LOG",
  76        exp.MaterializedProperty: lambda self, e: "MATERIALIZED",
  77        exp.NoPrimaryIndexProperty: lambda self, e: "NO PRIMARY INDEX",
  78        exp.OnCommitProperty: lambda self, e: f"ON COMMIT {'DELETE' if e.args.get('delete') else 'PRESERVE'} ROWS",
  79        exp.OnUpdateColumnConstraint: lambda self, e: f"ON UPDATE {self.sql(e, 'this')}",
  80        exp.PathColumnConstraint: lambda self, e: f"PATH {self.sql(e, 'this')}",
  81        exp.ReturnsProperty: lambda self, e: self.naked_property(e),
  82        exp.SetProperty: lambda self, e: f"{'MULTI' if e.args.get('multi') else ''}SET",
  83        exp.SettingsProperty: lambda self, e: f"SETTINGS{self.seg('')}{(self.expressions(e))}",
  84        exp.SqlSecurityProperty: lambda self, e: f"SQL SECURITY {'DEFINER' if e.args.get('definer') else 'INVOKER'}",
  85        exp.StabilityProperty: lambda self, e: e.name,
  86        exp.TemporaryProperty: lambda self, e: f"TEMPORARY",
  87        exp.ToTableProperty: lambda self, e: f"TO {self.sql(e.this)}",
  88        exp.TransientProperty: lambda self, e: "TRANSIENT",
  89        exp.TitleColumnConstraint: lambda self, e: f"TITLE {self.sql(e, 'this')}",
  90        exp.UppercaseColumnConstraint: lambda self, e: f"UPPERCASE",
  91        exp.VarMap: lambda self, e: self.func("MAP", e.args["keys"], e.args["values"]),
  92        exp.VolatileProperty: lambda self, e: "VOLATILE",
  93        exp.WithJournalTableProperty: lambda self, e: f"WITH JOURNAL TABLE={self.sql(e, 'this')}",
  94    }
  95
  96    # Whether or not null ordering is supported in order by
  97    NULL_ORDERING_SUPPORTED = True
  98
  99    # Whether or not locking reads (i.e. SELECT ... FOR UPDATE/SHARE) are supported
 100    LOCKING_READS_SUPPORTED = False
 101
 102    # Always do union distinct or union all
 103    EXPLICIT_UNION = False
 104
 105    # Wrap derived values in parens, usually standard but spark doesn't support it
 106    WRAP_DERIVED_VALUES = True
 107
 108    # Whether or not create function uses an AS before the RETURN
 109    CREATE_FUNCTION_RETURN_AS = True
 110
 111    # Whether or not MERGE ... WHEN MATCHED BY SOURCE is allowed
 112    MATCHED_BY_SOURCE = True
 113
 114    # Whether or not the INTERVAL expression works only with values like '1 day'
 115    SINGLE_STRING_INTERVAL = False
 116
 117    # Whether or not the plural form of date parts like day (i.e. "days") is supported in INTERVALs
 118    INTERVAL_ALLOWS_PLURAL_FORM = True
 119
 120    # Whether or not the TABLESAMPLE clause supports a method name, like BERNOULLI
 121    TABLESAMPLE_WITH_METHOD = True
 122
 123    # Whether or not to treat the number in TABLESAMPLE (50) as a percentage
 124    TABLESAMPLE_SIZE_IS_PERCENT = False
 125
 126    # Whether or not limit and fetch are supported (possible values: "ALL", "LIMIT", "FETCH")
 127    LIMIT_FETCH = "ALL"
 128
 129    # Whether or not a table is allowed to be renamed with a db
 130    RENAME_TABLE_WITH_DB = True
 131
 132    # The separator for grouping sets and rollups
 133    GROUPINGS_SEP = ","
 134
 135    # The string used for creating an index on a table
 136    INDEX_ON = "ON"
 137
 138    # Whether or not join hints should be generated
 139    JOIN_HINTS = True
 140
 141    # Whether or not table hints should be generated
 142    TABLE_HINTS = True
 143
 144    # Whether or not query hints should be generated
 145    QUERY_HINTS = True
 146
 147    # What kind of separator to use for query hints
 148    QUERY_HINT_SEP = ", "
 149
 150    # Whether or not comparing against booleans (e.g. x IS TRUE) is supported
 151    IS_BOOL_ALLOWED = True
 152
 153    # Whether or not to include the "SET" keyword in the "INSERT ... ON DUPLICATE KEY UPDATE" statement
 154    DUPLICATE_KEY_UPDATE_WITH_SET = True
 155
 156    # Whether or not to generate the limit as TOP <value> instead of LIMIT <value>
 157    LIMIT_IS_TOP = False
 158
 159    # Whether or not to generate INSERT INTO ... RETURNING or INSERT INTO RETURNING ...
 160    RETURNING_END = True
 161
 162    # Whether or not to generate the (+) suffix for columns used in old-style join conditions
 163    COLUMN_JOIN_MARKS_SUPPORTED = False
 164
 165    # Whether or not to generate an unquoted value for EXTRACT's date part argument
 166    EXTRACT_ALLOWS_QUOTES = True
 167
 168    # https://cloud.google.com/bigquery/docs/reference/standard-sql/query-syntax
 169    SELECT_KINDS: t.Tuple[str, ...] = ("STRUCT", "VALUE")
 170
 171    # Whether or not VALUES statements can be used as derived tables.
 172    # MySQL 5 and Redshift do not allow this, so when False, it will convert
 173    # SELECT * VALUES into SELECT UNION
 174    VALUES_AS_TABLE = True
 175
 176    TYPE_MAPPING = {
 177        exp.DataType.Type.NCHAR: "CHAR",
 178        exp.DataType.Type.NVARCHAR: "VARCHAR",
 179        exp.DataType.Type.MEDIUMTEXT: "TEXT",
 180        exp.DataType.Type.LONGTEXT: "TEXT",
 181        exp.DataType.Type.MEDIUMBLOB: "BLOB",
 182        exp.DataType.Type.LONGBLOB: "BLOB",
 183        exp.DataType.Type.INET: "INET",
 184    }
 185
 186    STAR_MAPPING = {
 187        "except": "EXCEPT",
 188        "replace": "REPLACE",
 189    }
 190
 191    TIME_PART_SINGULARS = {
 192        "microseconds": "microsecond",
 193        "seconds": "second",
 194        "minutes": "minute",
 195        "hours": "hour",
 196        "days": "day",
 197        "weeks": "week",
 198        "months": "month",
 199        "quarters": "quarter",
 200        "years": "year",
 201    }
 202
 203    TOKEN_MAPPING: t.Dict[TokenType, str] = {}
 204
 205    STRUCT_DELIMITER = ("<", ">")
 206
 207    PARAMETER_TOKEN = "@"
 208
 209    PROPERTIES_LOCATION = {
 210        exp.AlgorithmProperty: exp.Properties.Location.POST_CREATE,
 211        exp.AutoIncrementProperty: exp.Properties.Location.POST_SCHEMA,
 212        exp.BlockCompressionProperty: exp.Properties.Location.POST_NAME,
 213        exp.CharacterSetProperty: exp.Properties.Location.POST_SCHEMA,
 214        exp.ChecksumProperty: exp.Properties.Location.POST_NAME,
 215        exp.CollateProperty: exp.Properties.Location.POST_SCHEMA,
 216        exp.CopyGrantsProperty: exp.Properties.Location.POST_SCHEMA,
 217        exp.Cluster: exp.Properties.Location.POST_SCHEMA,
 218        exp.ClusteredByProperty: exp.Properties.Location.POST_SCHEMA,
 219        exp.DataBlocksizeProperty: exp.Properties.Location.POST_NAME,
 220        exp.DefinerProperty: exp.Properties.Location.POST_CREATE,
 221        exp.DictRange: exp.Properties.Location.POST_SCHEMA,
 222        exp.DictProperty: exp.Properties.Location.POST_SCHEMA,
 223        exp.DistKeyProperty: exp.Properties.Location.POST_SCHEMA,
 224        exp.DistStyleProperty: exp.Properties.Location.POST_SCHEMA,
 225        exp.EngineProperty: exp.Properties.Location.POST_SCHEMA,
 226        exp.ExecuteAsProperty: exp.Properties.Location.POST_SCHEMA,
 227        exp.ExternalProperty: exp.Properties.Location.POST_CREATE,
 228        exp.FallbackProperty: exp.Properties.Location.POST_NAME,
 229        exp.FileFormatProperty: exp.Properties.Location.POST_WITH,
 230        exp.FreespaceProperty: exp.Properties.Location.POST_NAME,
 231        exp.HeapProperty: exp.Properties.Location.POST_WITH,
 232        exp.IsolatedLoadingProperty: exp.Properties.Location.POST_NAME,
 233        exp.JournalProperty: exp.Properties.Location.POST_NAME,
 234        exp.LanguageProperty: exp.Properties.Location.POST_SCHEMA,
 235        exp.LikeProperty: exp.Properties.Location.POST_SCHEMA,
 236        exp.LocationProperty: exp.Properties.Location.POST_SCHEMA,
 237        exp.LockingProperty: exp.Properties.Location.POST_ALIAS,
 238        exp.LogProperty: exp.Properties.Location.POST_NAME,
 239        exp.MaterializedProperty: exp.Properties.Location.POST_CREATE,
 240        exp.MergeBlockRatioProperty: exp.Properties.Location.POST_NAME,
 241        exp.NoPrimaryIndexProperty: exp.Properties.Location.POST_EXPRESSION,
 242        exp.OnCommitProperty: exp.Properties.Location.POST_EXPRESSION,
 243        exp.Order: exp.Properties.Location.POST_SCHEMA,
 244        exp.PartitionedByProperty: exp.Properties.Location.POST_WITH,
 245        exp.PrimaryKey: exp.Properties.Location.POST_SCHEMA,
 246        exp.Property: exp.Properties.Location.POST_WITH,
 247        exp.ReturnsProperty: exp.Properties.Location.POST_SCHEMA,
 248        exp.RowFormatProperty: exp.Properties.Location.POST_SCHEMA,
 249        exp.RowFormatDelimitedProperty: exp.Properties.Location.POST_SCHEMA,
 250        exp.RowFormatSerdeProperty: exp.Properties.Location.POST_SCHEMA,
 251        exp.SchemaCommentProperty: exp.Properties.Location.POST_SCHEMA,
 252        exp.SerdeProperties: exp.Properties.Location.POST_SCHEMA,
 253        exp.Set: exp.Properties.Location.POST_SCHEMA,
 254        exp.SettingsProperty: exp.Properties.Location.POST_SCHEMA,
 255        exp.SetProperty: exp.Properties.Location.POST_CREATE,
 256        exp.SortKeyProperty: exp.Properties.Location.POST_SCHEMA,
 257        exp.SqlSecurityProperty: exp.Properties.Location.POST_CREATE,
 258        exp.StabilityProperty: exp.Properties.Location.POST_SCHEMA,
 259        exp.TemporaryProperty: exp.Properties.Location.POST_CREATE,
 260        exp.ToTableProperty: exp.Properties.Location.POST_SCHEMA,
 261        exp.TransientProperty: exp.Properties.Location.POST_CREATE,
 262        exp.MergeTreeTTL: exp.Properties.Location.POST_SCHEMA,
 263        exp.VolatileProperty: exp.Properties.Location.POST_CREATE,
 264        exp.WithDataProperty: exp.Properties.Location.POST_EXPRESSION,
 265        exp.WithJournalTableProperty: exp.Properties.Location.POST_NAME,
 266    }
 267
 268    # Keywords that can't be used as unquoted identifier names
 269    RESERVED_KEYWORDS: t.Set[str] = set()
 270
 271    # Expressions whose comments are separated from them for better formatting
 272    WITH_SEPARATED_COMMENTS: t.Tuple[t.Type[exp.Expression], ...] = (
 273        exp.Delete,
 274        exp.Drop,
 275        exp.From,
 276        exp.Insert,
 277        exp.Select,
 278        exp.Update,
 279        exp.Where,
 280        exp.With,
 281    )
 282
 283    # Expressions that can remain unwrapped when appearing in the context of an INTERVAL
 284    UNWRAPPED_INTERVAL_VALUES: t.Tuple[t.Type[exp.Expression], ...] = (
 285        exp.Column,
 286        exp.Literal,
 287        exp.Neg,
 288        exp.Paren,
 289    )
 290
 291    SENTINEL_LINE_BREAK = "__SQLGLOT__LB__"
 292
 293    # Autofilled
 294    INVERSE_TIME_MAPPING: t.Dict[str, str] = {}
 295    INVERSE_TIME_TRIE: t.Dict = {}
 296    INDEX_OFFSET = 0
 297    UNNEST_COLUMN_ONLY = False
 298    ALIAS_POST_TABLESAMPLE = False
 299    IDENTIFIERS_CAN_START_WITH_DIGIT = False
 300    STRICT_STRING_CONCAT = False
 301    NORMALIZE_FUNCTIONS: bool | str = "upper"
 302    NULL_ORDERING = "nulls_are_small"
 303    ESCAPE_LINE_BREAK = False
 304
 305    can_identify: t.Callable[[str, str | bool], bool]
 306
 307    # Delimiters for quotes, identifiers and the corresponding escape characters
 308    QUOTE_START = "'"
 309    QUOTE_END = "'"
 310    IDENTIFIER_START = '"'
 311    IDENTIFIER_END = '"'
 312    STRING_ESCAPE = "'"
 313    IDENTIFIER_ESCAPE = '"'
 314
 315    # Delimiters for bit, hex, byte and raw literals
 316    BIT_START: t.Optional[str] = None
 317    BIT_END: t.Optional[str] = None
 318    HEX_START: t.Optional[str] = None
 319    HEX_END: t.Optional[str] = None
 320    BYTE_START: t.Optional[str] = None
 321    BYTE_END: t.Optional[str] = None
 322
 323    __slots__ = (
 324        "pretty",
 325        "identify",
 326        "normalize",
 327        "pad",
 328        "_indent",
 329        "normalize_functions",
 330        "unsupported_level",
 331        "max_unsupported",
 332        "leading_comma",
 333        "max_text_width",
 334        "comments",
 335        "unsupported_messages",
 336        "_escaped_quote_end",
 337        "_escaped_identifier_end",
 338        "_cache",
 339    )
 340
 341    def __init__(
 342        self,
 343        pretty: t.Optional[bool] = None,
 344        identify: str | bool = False,
 345        normalize: bool = False,
 346        pad: int = 2,
 347        indent: int = 2,
 348        normalize_functions: t.Optional[str | bool] = None,
 349        unsupported_level: ErrorLevel = ErrorLevel.WARN,
 350        max_unsupported: int = 3,
 351        leading_comma: bool = False,
 352        max_text_width: int = 80,
 353        comments: bool = True,
 354    ):
 355        import sqlglot
 356
 357        self.pretty = pretty if pretty is not None else sqlglot.pretty
 358        self.identify = identify
 359        self.normalize = normalize
 360        self.pad = pad
 361        self._indent = indent
 362        self.unsupported_level = unsupported_level
 363        self.max_unsupported = max_unsupported
 364        self.leading_comma = leading_comma
 365        self.max_text_width = max_text_width
 366        self.comments = comments
 367
 368        # This is both a Dialect property and a Generator argument, so we prioritize the latter
 369        self.normalize_functions = (
 370            self.NORMALIZE_FUNCTIONS if normalize_functions is None else normalize_functions
 371        )
 372
 373        self.unsupported_messages: t.List[str] = []
 374        self._escaped_quote_end: str = self.STRING_ESCAPE + self.QUOTE_END
 375        self._escaped_identifier_end: str = self.IDENTIFIER_ESCAPE + self.IDENTIFIER_END
 376        self._cache: t.Optional[t.Dict[int, str]] = None
 377
 378    def generate(
 379        self,
 380        expression: t.Optional[exp.Expression],
 381        cache: t.Optional[t.Dict[int, str]] = None,
 382    ) -> str:
 383        """
 384        Generates the SQL string corresponding to the given syntax tree.
 385
 386        Args:
 387            expression: The syntax tree.
 388            cache: An optional sql string cache. This leverages the hash of an Expression
 389                which can be slow to compute, so only use it if you set _hash on each node.
 390
 391        Returns:
 392            The SQL string corresponding to `expression`.
 393        """
 394        if cache is not None:
 395            self._cache = cache
 396
 397        self.unsupported_messages = []
 398        sql = self.sql(expression).strip()
 399        self._cache = None
 400
 401        if self.unsupported_level == ErrorLevel.IGNORE:
 402            return sql
 403
 404        if self.unsupported_level == ErrorLevel.WARN:
 405            for msg in self.unsupported_messages:
 406                logger.warning(msg)
 407        elif self.unsupported_level == ErrorLevel.RAISE and self.unsupported_messages:
 408            raise UnsupportedError(concat_messages(self.unsupported_messages, self.max_unsupported))
 409
 410        if self.pretty:
 411            sql = sql.replace(self.SENTINEL_LINE_BREAK, "\n")
 412        return sql
 413
 414    def unsupported(self, message: str) -> None:
 415        if self.unsupported_level == ErrorLevel.IMMEDIATE:
 416            raise UnsupportedError(message)
 417        self.unsupported_messages.append(message)
 418
 419    def sep(self, sep: str = " ") -> str:
 420        return f"{sep.strip()}\n" if self.pretty else sep
 421
 422    def seg(self, sql: str, sep: str = " ") -> str:
 423        return f"{self.sep(sep)}{sql}"
 424
 425    def pad_comment(self, comment: str) -> str:
 426        comment = " " + comment if comment[0].strip() else comment
 427        comment = comment + " " if comment[-1].strip() else comment
 428        return comment
 429
 430    def maybe_comment(
 431        self,
 432        sql: str,
 433        expression: t.Optional[exp.Expression] = None,
 434        comments: t.Optional[t.List[str]] = None,
 435    ) -> str:
 436        comments = (
 437            ((expression and expression.comments) if comments is None else comments)  # type: ignore
 438            if self.comments
 439            else None
 440        )
 441
 442        if not comments or isinstance(expression, exp.Binary):
 443            return sql
 444
 445        sep = "\n" if self.pretty else " "
 446        comments_sql = sep.join(
 447            f"/*{self.pad_comment(comment)}*/" for comment in comments if comment
 448        )
 449
 450        if not comments_sql:
 451            return sql
 452
 453        if isinstance(expression, self.WITH_SEPARATED_COMMENTS):
 454            return (
 455                f"{self.sep()}{comments_sql}{sql}"
 456                if sql[0].isspace()
 457                else f"{comments_sql}{self.sep()}{sql}"
 458            )
 459
 460        return f"{sql} {comments_sql}"
 461
 462    def wrap(self, expression: exp.Expression | str) -> str:
 463        this_sql = self.indent(
 464            self.sql(expression)
 465            if isinstance(expression, (exp.Select, exp.Union))
 466            else self.sql(expression, "this"),
 467            level=1,
 468            pad=0,
 469        )
 470        return f"({self.sep('')}{this_sql}{self.seg(')', sep='')}"
 471
 472    def no_identify(self, func: t.Callable[..., str], *args, **kwargs) -> str:
 473        original = self.identify
 474        self.identify = False
 475        result = func(*args, **kwargs)
 476        self.identify = original
 477        return result
 478
 479    def normalize_func(self, name: str) -> str:
 480        if self.normalize_functions == "upper" or self.normalize_functions is True:
 481            return name.upper()
 482        if self.normalize_functions == "lower":
 483            return name.lower()
 484        return name
 485
 486    def indent(
 487        self,
 488        sql: str,
 489        level: int = 0,
 490        pad: t.Optional[int] = None,
 491        skip_first: bool = False,
 492        skip_last: bool = False,
 493    ) -> str:
 494        if not self.pretty:
 495            return sql
 496
 497        pad = self.pad if pad is None else pad
 498        lines = sql.split("\n")
 499
 500        return "\n".join(
 501            line
 502            if (skip_first and i == 0) or (skip_last and i == len(lines) - 1)
 503            else f"{' ' * (level * self._indent + pad)}{line}"
 504            for i, line in enumerate(lines)
 505        )
 506
 507    def sql(
 508        self,
 509        expression: t.Optional[str | exp.Expression],
 510        key: t.Optional[str] = None,
 511        comment: bool = True,
 512    ) -> str:
 513        if not expression:
 514            return ""
 515
 516        if isinstance(expression, str):
 517            return expression
 518
 519        if key:
 520            value = expression.args.get(key)
 521            if value:
 522                return self.sql(value)
 523            return ""
 524
 525        if self._cache is not None:
 526            expression_id = hash(expression)
 527
 528            if expression_id in self._cache:
 529                return self._cache[expression_id]
 530
 531        transform = self.TRANSFORMS.get(expression.__class__)
 532
 533        if callable(transform):
 534            sql = transform(self, expression)
 535        elif transform:
 536            sql = transform
 537        elif isinstance(expression, exp.Expression):
 538            exp_handler_name = f"{expression.key}_sql"
 539
 540            if hasattr(self, exp_handler_name):
 541                sql = getattr(self, exp_handler_name)(expression)
 542            elif isinstance(expression, exp.Func):
 543                sql = self.function_fallback_sql(expression)
 544            elif isinstance(expression, exp.Property):
 545                sql = self.property_sql(expression)
 546            else:
 547                raise ValueError(f"Unsupported expression type {expression.__class__.__name__}")
 548        else:
 549            raise ValueError(f"Expected an Expression. Received {type(expression)}: {expression}")
 550
 551        sql = self.maybe_comment(sql, expression) if self.comments and comment else sql
 552
 553        if self._cache is not None:
 554            self._cache[expression_id] = sql
 555        return sql
 556
 557    def uncache_sql(self, expression: exp.Uncache) -> str:
 558        table = self.sql(expression, "this")
 559        exists_sql = " IF EXISTS" if expression.args.get("exists") else ""
 560        return f"UNCACHE TABLE{exists_sql} {table}"
 561
 562    def cache_sql(self, expression: exp.Cache) -> str:
 563        lazy = " LAZY" if expression.args.get("lazy") else ""
 564        table = self.sql(expression, "this")
 565        options = expression.args.get("options")
 566        options = f" OPTIONS({self.sql(options[0])} = {self.sql(options[1])})" if options else ""
 567        sql = self.sql(expression, "expression")
 568        sql = f" AS{self.sep()}{sql}" if sql else ""
 569        sql = f"CACHE{lazy} TABLE {table}{options}{sql}"
 570        return self.prepend_ctes(expression, sql)
 571
 572    def characterset_sql(self, expression: exp.CharacterSet) -> str:
 573        if isinstance(expression.parent, exp.Cast):
 574            return f"CHAR CHARACTER SET {self.sql(expression, 'this')}"
 575        default = "DEFAULT " if expression.args.get("default") else ""
 576        return f"{default}CHARACTER SET={self.sql(expression, 'this')}"
 577
 578    def column_sql(self, expression: exp.Column) -> str:
 579        join_mark = " (+)" if expression.args.get("join_mark") else ""
 580
 581        if join_mark and not self.COLUMN_JOIN_MARKS_SUPPORTED:
 582            join_mark = ""
 583            self.unsupported("Outer join syntax using the (+) operator is not supported.")
 584
 585        column = ".".join(
 586            self.sql(part)
 587            for part in (
 588                expression.args.get("catalog"),
 589                expression.args.get("db"),
 590                expression.args.get("table"),
 591                expression.args.get("this"),
 592            )
 593            if part
 594        )
 595
 596        return f"{column}{join_mark}"
 597
 598    def columnposition_sql(self, expression: exp.ColumnPosition) -> str:
 599        this = self.sql(expression, "this")
 600        this = f" {this}" if this else ""
 601        position = self.sql(expression, "position")
 602        return f"{position}{this}"
 603
 604    def columndef_sql(self, expression: exp.ColumnDef, sep: str = " ") -> str:
 605        column = self.sql(expression, "this")
 606        kind = self.sql(expression, "kind")
 607        constraints = self.expressions(expression, key="constraints", sep=" ", flat=True)
 608        exists = "IF NOT EXISTS " if expression.args.get("exists") else ""
 609        kind = f"{sep}{kind}" if kind else ""
 610        constraints = f" {constraints}" if constraints else ""
 611        position = self.sql(expression, "position")
 612        position = f" {position}" if position else ""
 613
 614        return f"{exists}{column}{kind}{constraints}{position}"
 615
 616    def columnconstraint_sql(self, expression: exp.ColumnConstraint) -> str:
 617        this = self.sql(expression, "this")
 618        kind_sql = self.sql(expression, "kind").strip()
 619        return f"CONSTRAINT {this} {kind_sql}" if this else kind_sql
 620
 621    def autoincrementcolumnconstraint_sql(self, _) -> str:
 622        return self.token_sql(TokenType.AUTO_INCREMENT)
 623
 624    def compresscolumnconstraint_sql(self, expression: exp.CompressColumnConstraint) -> str:
 625        if isinstance(expression.this, list):
 626            this = self.wrap(self.expressions(expression, key="this", flat=True))
 627        else:
 628            this = self.sql(expression, "this")
 629
 630        return f"COMPRESS {this}"
 631
 632    def generatedasidentitycolumnconstraint_sql(
 633        self, expression: exp.GeneratedAsIdentityColumnConstraint
 634    ) -> str:
 635        this = ""
 636        if expression.this is not None:
 637            on_null = "ON NULL " if expression.args.get("on_null") else ""
 638            this = " ALWAYS " if expression.this else f" BY DEFAULT {on_null}"
 639
 640        start = expression.args.get("start")
 641        start = f"START WITH {start}" if start else ""
 642        increment = expression.args.get("increment")
 643        increment = f" INCREMENT BY {increment}" if increment else ""
 644        minvalue = expression.args.get("minvalue")
 645        minvalue = f" MINVALUE {minvalue}" if minvalue else ""
 646        maxvalue = expression.args.get("maxvalue")
 647        maxvalue = f" MAXVALUE {maxvalue}" if maxvalue else ""
 648        cycle = expression.args.get("cycle")
 649        cycle_sql = ""
 650
 651        if cycle is not None:
 652            cycle_sql = f"{' NO' if not cycle else ''} CYCLE"
 653            cycle_sql = cycle_sql.strip() if not start and not increment else cycle_sql
 654
 655        sequence_opts = ""
 656        if start or increment or cycle_sql:
 657            sequence_opts = f"{start}{increment}{minvalue}{maxvalue}{cycle_sql}"
 658            sequence_opts = f" ({sequence_opts.strip()})"
 659
 660        expr = self.sql(expression, "expression")
 661        expr = f"({expr})" if expr else "IDENTITY"
 662
 663        return f"GENERATED{this}AS {expr}{sequence_opts}"
 664
 665    def notnullcolumnconstraint_sql(self, expression: exp.NotNullColumnConstraint) -> str:
 666        return f"{'' if expression.args.get('allow_null') else 'NOT '}NULL"
 667
 668    def primarykeycolumnconstraint_sql(self, expression: exp.PrimaryKeyColumnConstraint) -> str:
 669        desc = expression.args.get("desc")
 670        if desc is not None:
 671            return f"PRIMARY KEY{' DESC' if desc else ' ASC'}"
 672        return f"PRIMARY KEY"
 673
 674    def uniquecolumnconstraint_sql(self, expression: exp.UniqueColumnConstraint) -> str:
 675        this = self.sql(expression, "this")
 676        this = f" {this}" if this else ""
 677        return f"UNIQUE{this}"
 678
 679    def createable_sql(
 680        self, expression: exp.Create, locations: dict[exp.Properties.Location, list[exp.Property]]
 681    ) -> str:
 682        return self.sql(expression, "this")
 683
 684    def create_sql(self, expression: exp.Create) -> str:
 685        kind = self.sql(expression, "kind").upper()
 686        properties = expression.args.get("properties")
 687        properties_locs = self.locate_properties(properties) if properties else {}
 688
 689        this = self.createable_sql(expression, properties_locs)
 690
 691        properties_sql = ""
 692        if properties_locs.get(exp.Properties.Location.POST_SCHEMA) or properties_locs.get(
 693            exp.Properties.Location.POST_WITH
 694        ):
 695            properties_sql = self.sql(
 696                exp.Properties(
 697                    expressions=[
 698                        *properties_locs[exp.Properties.Location.POST_SCHEMA],
 699                        *properties_locs[exp.Properties.Location.POST_WITH],
 700                    ]
 701                )
 702            )
 703
 704        begin = " BEGIN" if expression.args.get("begin") else ""
 705        expression_sql = self.sql(expression, "expression")
 706        if expression_sql:
 707            expression_sql = f"{begin}{self.sep()}{expression_sql}"
 708
 709            if self.CREATE_FUNCTION_RETURN_AS or not isinstance(expression.expression, exp.Return):
 710                if properties_locs.get(exp.Properties.Location.POST_ALIAS):
 711                    postalias_props_sql = self.properties(
 712                        exp.Properties(
 713                            expressions=properties_locs[exp.Properties.Location.POST_ALIAS]
 714                        ),
 715                        wrapped=False,
 716                    )
 717                    expression_sql = f" AS {postalias_props_sql}{expression_sql}"
 718                else:
 719                    expression_sql = f" AS{expression_sql}"
 720
 721        postindex_props_sql = ""
 722        if properties_locs.get(exp.Properties.Location.POST_INDEX):
 723            postindex_props_sql = self.properties(
 724                exp.Properties(expressions=properties_locs[exp.Properties.Location.POST_INDEX]),
 725                wrapped=False,
 726                prefix=" ",
 727            )
 728
 729        indexes = self.expressions(expression, key="indexes", indent=False, sep=" ")
 730        indexes = f" {indexes}" if indexes else ""
 731        index_sql = indexes + postindex_props_sql
 732
 733        replace = " OR REPLACE" if expression.args.get("replace") else ""
 734        unique = " UNIQUE" if expression.args.get("unique") else ""
 735
 736        postcreate_props_sql = ""
 737        if properties_locs.get(exp.Properties.Location.POST_CREATE):
 738            postcreate_props_sql = self.properties(
 739                exp.Properties(expressions=properties_locs[exp.Properties.Location.POST_CREATE]),
 740                sep=" ",
 741                prefix=" ",
 742                wrapped=False,
 743            )
 744
 745        modifiers = "".join((replace, unique, postcreate_props_sql))
 746
 747        postexpression_props_sql = ""
 748        if properties_locs.get(exp.Properties.Location.POST_EXPRESSION):
 749            postexpression_props_sql = self.properties(
 750                exp.Properties(
 751                    expressions=properties_locs[exp.Properties.Location.POST_EXPRESSION]
 752                ),
 753                sep=" ",
 754                prefix=" ",
 755                wrapped=False,
 756            )
 757
 758        exists_sql = " IF NOT EXISTS" if expression.args.get("exists") else ""
 759        no_schema_binding = (
 760            " WITH NO SCHEMA BINDING" if expression.args.get("no_schema_binding") else ""
 761        )
 762
 763        clone = self.sql(expression, "clone")
 764        clone = f" {clone}" if clone else ""
 765
 766        expression_sql = f"CREATE{modifiers} {kind}{exists_sql} {this}{properties_sql}{expression_sql}{postexpression_props_sql}{index_sql}{no_schema_binding}{clone}"
 767        return self.prepend_ctes(expression, expression_sql)
 768
 769    def clone_sql(self, expression: exp.Clone) -> str:
 770        this = self.sql(expression, "this")
 771        when = self.sql(expression, "when")
 772
 773        if when:
 774            kind = self.sql(expression, "kind")
 775            expr = self.sql(expression, "expression")
 776            return f"CLONE {this} {when} ({kind} => {expr})"
 777
 778        return f"CLONE {this}"
 779
 780    def describe_sql(self, expression: exp.Describe) -> str:
 781        return f"DESCRIBE {self.sql(expression, 'this')}"
 782
 783    def prepend_ctes(self, expression: exp.Expression, sql: str) -> str:
 784        with_ = self.sql(expression, "with")
 785        if with_:
 786            sql = f"{with_}{self.sep()}{sql}"
 787        return sql
 788
 789    def with_sql(self, expression: exp.With) -> str:
 790        sql = self.expressions(expression, flat=True)
 791        recursive = "RECURSIVE " if expression.args.get("recursive") else ""
 792
 793        return f"WITH {recursive}{sql}"
 794
 795    def cte_sql(self, expression: exp.CTE) -> str:
 796        alias = self.sql(expression, "alias")
 797        return f"{alias} AS {self.wrap(expression)}"
 798
 799    def tablealias_sql(self, expression: exp.TableAlias) -> str:
 800        alias = self.sql(expression, "this")
 801        columns = self.expressions(expression, key="columns", flat=True)
 802        columns = f"({columns})" if columns else ""
 803        return f"{alias}{columns}"
 804
 805    def bitstring_sql(self, expression: exp.BitString) -> str:
 806        this = self.sql(expression, "this")
 807        if self.BIT_START:
 808            return f"{self.BIT_START}{this}{self.BIT_END}"
 809        return f"{int(this, 2)}"
 810
 811    def hexstring_sql(self, expression: exp.HexString) -> str:
 812        this = self.sql(expression, "this")
 813        if self.HEX_START:
 814            return f"{self.HEX_START}{this}{self.HEX_END}"
 815        return f"{int(this, 16)}"
 816
 817    def bytestring_sql(self, expression: exp.ByteString) -> str:
 818        this = self.sql(expression, "this")
 819        if self.BYTE_START:
 820            return f"{self.BYTE_START}{this}{self.BYTE_END}"
 821        return this
 822
 823    def rawstring_sql(self, expression: exp.RawString) -> str:
 824        string = self.escape_str(expression.this.replace("\\", "\\\\"))
 825        return f"{self.QUOTE_START}{string}{self.QUOTE_END}"
 826
 827    def datatypesize_sql(self, expression: exp.DataTypeSize) -> str:
 828        this = self.sql(expression, "this")
 829        specifier = self.sql(expression, "expression")
 830        specifier = f" {specifier}" if specifier else ""
 831        return f"{this}{specifier}"
 832
 833    def datatype_sql(self, expression: exp.DataType) -> str:
 834        type_value = expression.this
 835        type_sql = (
 836            self.TYPE_MAPPING.get(type_value, type_value.value)
 837            if isinstance(type_value, exp.DataType.Type)
 838            else type_value
 839        )
 840        nested = ""
 841        interior = self.expressions(expression, flat=True)
 842        values = ""
 843        if interior:
 844            if expression.args.get("nested"):
 845                nested = f"{self.STRUCT_DELIMITER[0]}{interior}{self.STRUCT_DELIMITER[1]}"
 846                if expression.args.get("values") is not None:
 847                    delimiters = ("[", "]") if type_value == exp.DataType.Type.ARRAY else ("(", ")")
 848                    values = self.expressions(expression, key="values", flat=True)
 849                    values = f"{delimiters[0]}{values}{delimiters[1]}"
 850            else:
 851                nested = f"({interior})"
 852
 853        return f"{type_sql}{nested}{values}"
 854
 855    def directory_sql(self, expression: exp.Directory) -> str:
 856        local = "LOCAL " if expression.args.get("local") else ""
 857        row_format = self.sql(expression, "row_format")
 858        row_format = f" {row_format}" if row_format else ""
 859        return f"{local}DIRECTORY {self.sql(expression, 'this')}{row_format}"
 860
 861    def delete_sql(self, expression: exp.Delete) -> str:
 862        this = self.sql(expression, "this")
 863        this = f" FROM {this}" if this else ""
 864        using = self.sql(expression, "using")
 865        using = f" USING {using}" if using else ""
 866        where = self.sql(expression, "where")
 867        returning = self.sql(expression, "returning")
 868        limit = self.sql(expression, "limit")
 869        tables = self.expressions(expression, key="tables")
 870        tables = f" {tables}" if tables else ""
 871        if self.RETURNING_END:
 872            expression_sql = f"{this}{using}{where}{returning}{limit}"
 873        else:
 874            expression_sql = f"{returning}{this}{using}{where}{limit}"
 875        return self.prepend_ctes(expression, f"DELETE{tables}{expression_sql}")
 876
 877    def drop_sql(self, expression: exp.Drop) -> str:
 878        this = self.sql(expression, "this")
 879        kind = expression.args["kind"]
 880        exists_sql = " IF EXISTS " if expression.args.get("exists") else " "
 881        temporary = " TEMPORARY" if expression.args.get("temporary") else ""
 882        materialized = " MATERIALIZED" if expression.args.get("materialized") else ""
 883        cascade = " CASCADE" if expression.args.get("cascade") else ""
 884        constraints = " CONSTRAINTS" if expression.args.get("constraints") else ""
 885        purge = " PURGE" if expression.args.get("purge") else ""
 886        return (
 887            f"DROP{temporary}{materialized} {kind}{exists_sql}{this}{cascade}{constraints}{purge}"
 888        )
 889
 890    def except_sql(self, expression: exp.Except) -> str:
 891        return self.prepend_ctes(
 892            expression,
 893            self.set_operation(expression, self.except_op(expression)),
 894        )
 895
 896    def except_op(self, expression: exp.Except) -> str:
 897        return f"EXCEPT{'' if expression.args.get('distinct') else ' ALL'}"
 898
 899    def fetch_sql(self, expression: exp.Fetch) -> str:
 900        direction = expression.args.get("direction")
 901        direction = f" {direction.upper()}" if direction else ""
 902        count = expression.args.get("count")
 903        count = f" {count}" if count else ""
 904        if expression.args.get("percent"):
 905            count = f"{count} PERCENT"
 906        with_ties_or_only = "WITH TIES" if expression.args.get("with_ties") else "ONLY"
 907        return f"{self.seg('FETCH')}{direction}{count} ROWS {with_ties_or_only}"
 908
 909    def filter_sql(self, expression: exp.Filter) -> str:
 910        this = self.sql(expression, "this")
 911        where = self.sql(expression, "expression")[1:]  # where has a leading space
 912        return f"{this} FILTER({where})"
 913
 914    def hint_sql(self, expression: exp.Hint) -> str:
 915        if not self.QUERY_HINTS:
 916            self.unsupported("Hints are not supported")
 917            return ""
 918
 919        return f" /*+ {self.expressions(expression, sep=self.QUERY_HINT_SEP).strip()} */"
 920
 921    def index_sql(self, expression: exp.Index) -> str:
 922        unique = "UNIQUE " if expression.args.get("unique") else ""
 923        primary = "PRIMARY " if expression.args.get("primary") else ""
 924        amp = "AMP " if expression.args.get("amp") else ""
 925        name = self.sql(expression, "this")
 926        name = f"{name} " if name else ""
 927        table = self.sql(expression, "table")
 928        table = f"{self.INDEX_ON} {table} " if table else ""
 929        using = self.sql(expression, "using")
 930        using = f"USING {using} " if using else ""
 931        index = "INDEX " if not table else ""
 932        columns = self.expressions(expression, key="columns", flat=True)
 933        columns = f"({columns})" if columns else ""
 934        partition_by = self.expressions(expression, key="partition_by", flat=True)
 935        partition_by = f" PARTITION BY {partition_by}" if partition_by else ""
 936        return f"{unique}{primary}{amp}{index}{name}{table}{using}{columns}{partition_by}"
 937
 938    def identifier_sql(self, expression: exp.Identifier) -> str:
 939        text = expression.name
 940        lower = text.lower()
 941        text = lower if self.normalize and not expression.quoted else text
 942        text = text.replace(self.IDENTIFIER_END, self._escaped_identifier_end)
 943        if (
 944            expression.quoted
 945            or self.can_identify(text, self.identify)
 946            or lower in self.RESERVED_KEYWORDS
 947            or (not self.IDENTIFIERS_CAN_START_WITH_DIGIT and text[:1].isdigit())
 948        ):
 949            text = f"{self.IDENTIFIER_START}{text}{self.IDENTIFIER_END}"
 950        return text
 951
 952    def inputoutputformat_sql(self, expression: exp.InputOutputFormat) -> str:
 953        input_format = self.sql(expression, "input_format")
 954        input_format = f"INPUTFORMAT {input_format}" if input_format else ""
 955        output_format = self.sql(expression, "output_format")
 956        output_format = f"OUTPUTFORMAT {output_format}" if output_format else ""
 957        return self.sep().join((input_format, output_format))
 958
 959    def national_sql(self, expression: exp.National, prefix: str = "N") -> str:
 960        string = self.sql(exp.Literal.string(expression.name))
 961        return f"{prefix}{string}"
 962
 963    def partition_sql(self, expression: exp.Partition) -> str:
 964        return f"PARTITION({self.expressions(expression, flat=True)})"
 965
 966    def properties_sql(self, expression: exp.Properties) -> str:
 967        root_properties = []
 968        with_properties = []
 969
 970        for p in expression.expressions:
 971            p_loc = self.PROPERTIES_LOCATION[p.__class__]
 972            if p_loc == exp.Properties.Location.POST_WITH:
 973                with_properties.append(p)
 974            elif p_loc == exp.Properties.Location.POST_SCHEMA:
 975                root_properties.append(p)
 976
 977        return self.root_properties(
 978            exp.Properties(expressions=root_properties)
 979        ) + self.with_properties(exp.Properties(expressions=with_properties))
 980
 981    def root_properties(self, properties: exp.Properties) -> str:
 982        if properties.expressions:
 983            return self.sep() + self.expressions(properties, indent=False, sep=" ")
 984        return ""
 985
 986    def properties(
 987        self,
 988        properties: exp.Properties,
 989        prefix: str = "",
 990        sep: str = ", ",
 991        suffix: str = "",
 992        wrapped: bool = True,
 993    ) -> str:
 994        if properties.expressions:
 995            expressions = self.expressions(properties, sep=sep, indent=False)
 996            if expressions:
 997                expressions = self.wrap(expressions) if wrapped else expressions
 998                return f"{prefix}{' ' if prefix and prefix != ' ' else ''}{expressions}{suffix}"
 999        return ""
1000
1001    def with_properties(self, properties: exp.Properties) -> str:
1002        return self.properties(properties, prefix=self.seg("WITH"))
1003
1004    def locate_properties(
1005        self, properties: exp.Properties
1006    ) -> t.Dict[exp.Properties.Location, list[exp.Property]]:
1007        properties_locs: t.Dict[exp.Properties.Location, list[exp.Property]] = {
1008            key: [] for key in exp.Properties.Location
1009        }
1010
1011        for p in properties.expressions:
1012            p_loc = self.PROPERTIES_LOCATION[p.__class__]
1013            if p_loc == exp.Properties.Location.POST_NAME:
1014                properties_locs[exp.Properties.Location.POST_NAME].append(p)
1015            elif p_loc == exp.Properties.Location.POST_INDEX:
1016                properties_locs[exp.Properties.Location.POST_INDEX].append(p)
1017            elif p_loc == exp.Properties.Location.POST_SCHEMA:
1018                properties_locs[exp.Properties.Location.POST_SCHEMA].append(p)
1019            elif p_loc == exp.Properties.Location.POST_WITH:
1020                properties_locs[exp.Properties.Location.POST_WITH].append(p)
1021            elif p_loc == exp.Properties.Location.POST_CREATE:
1022                properties_locs[exp.Properties.Location.POST_CREATE].append(p)
1023            elif p_loc == exp.Properties.Location.POST_ALIAS:
1024                properties_locs[exp.Properties.Location.POST_ALIAS].append(p)
1025            elif p_loc == exp.Properties.Location.POST_EXPRESSION:
1026                properties_locs[exp.Properties.Location.POST_EXPRESSION].append(p)
1027            elif p_loc == exp.Properties.Location.UNSUPPORTED:
1028                self.unsupported(f"Unsupported property {p.key}")
1029
1030        return properties_locs
1031
1032    def property_sql(self, expression: exp.Property) -> str:
1033        property_cls = expression.__class__
1034        if property_cls == exp.Property:
1035            return f"{expression.name}={self.sql(expression, 'value')}"
1036
1037        property_name = exp.Properties.PROPERTY_TO_NAME.get(property_cls)
1038        if not property_name:
1039            self.unsupported(f"Unsupported property {expression.key}")
1040
1041        return f"{property_name}={self.sql(expression, 'this')}"
1042
1043    def likeproperty_sql(self, expression: exp.LikeProperty) -> str:
1044        options = " ".join(f"{e.name} {self.sql(e, 'value')}" for e in expression.expressions)
1045        options = f" {options}" if options else ""
1046        return f"LIKE {self.sql(expression, 'this')}{options}"
1047
1048    def fallbackproperty_sql(self, expression: exp.FallbackProperty) -> str:
1049        no = "NO " if expression.args.get("no") else ""
1050        protection = " PROTECTION" if expression.args.get("protection") else ""
1051        return f"{no}FALLBACK{protection}"
1052
1053    def journalproperty_sql(self, expression: exp.JournalProperty) -> str:
1054        no = "NO " if expression.args.get("no") else ""
1055        local = expression.args.get("local")
1056        local = f"{local} " if local else ""
1057        dual = "DUAL " if expression.args.get("dual") else ""
1058        before = "BEFORE " if expression.args.get("before") else ""
1059        after = "AFTER " if expression.args.get("after") else ""
1060        return f"{no}{local}{dual}{before}{after}JOURNAL"
1061
1062    def freespaceproperty_sql(self, expression: exp.FreespaceProperty) -> str:
1063        freespace = self.sql(expression, "this")
1064        percent = " PERCENT" if expression.args.get("percent") else ""
1065        return f"FREESPACE={freespace}{percent}"
1066
1067    def checksumproperty_sql(self, expression: exp.ChecksumProperty) -> str:
1068        if expression.args.get("default"):
1069            property = "DEFAULT"
1070        elif expression.args.get("on"):
1071            property = "ON"
1072        else:
1073            property = "OFF"
1074        return f"CHECKSUM={property}"
1075
1076    def mergeblockratioproperty_sql(self, expression: exp.MergeBlockRatioProperty) -> str:
1077        if expression.args.get("no"):
1078            return "NO MERGEBLOCKRATIO"
1079        if expression.args.get("default"):
1080            return "DEFAULT MERGEBLOCKRATIO"
1081
1082        percent = " PERCENT" if expression.args.get("percent") else ""
1083        return f"MERGEBLOCKRATIO={self.sql(expression, 'this')}{percent}"
1084
1085    def datablocksizeproperty_sql(self, expression: exp.DataBlocksizeProperty) -> str:
1086        default = expression.args.get("default")
1087        minimum = expression.args.get("minimum")
1088        maximum = expression.args.get("maximum")
1089        if default or minimum or maximum:
1090            if default:
1091                prop = "DEFAULT"
1092            elif minimum:
1093                prop = "MINIMUM"
1094            else:
1095                prop = "MAXIMUM"
1096            return f"{prop} DATABLOCKSIZE"
1097        units = expression.args.get("units")
1098        units = f" {units}" if units else ""
1099        return f"DATABLOCKSIZE={self.sql(expression, 'size')}{units}"
1100
1101    def blockcompressionproperty_sql(self, expression: exp.BlockCompressionProperty) -> str:
1102        autotemp = expression.args.get("autotemp")
1103        always = expression.args.get("always")
1104        default = expression.args.get("default")
1105        manual = expression.args.get("manual")
1106        never = expression.args.get("never")
1107
1108        if autotemp is not None:
1109            prop = f"AUTOTEMP({self.expressions(autotemp)})"
1110        elif always:
1111            prop = "ALWAYS"
1112        elif default:
1113            prop = "DEFAULT"
1114        elif manual:
1115            prop = "MANUAL"
1116        elif never:
1117            prop = "NEVER"
1118        return f"BLOCKCOMPRESSION={prop}"
1119
1120    def isolatedloadingproperty_sql(self, expression: exp.IsolatedLoadingProperty) -> str:
1121        no = expression.args.get("no")
1122        no = " NO" if no else ""
1123        concurrent = expression.args.get("concurrent")
1124        concurrent = " CONCURRENT" if concurrent else ""
1125
1126        for_ = ""
1127        if expression.args.get("for_all"):
1128            for_ = " FOR ALL"
1129        elif expression.args.get("for_insert"):
1130            for_ = " FOR INSERT"
1131        elif expression.args.get("for_none"):
1132            for_ = " FOR NONE"
1133        return f"WITH{no}{concurrent} ISOLATED LOADING{for_}"
1134
1135    def lockingproperty_sql(self, expression: exp.LockingProperty) -> str:
1136        kind = expression.args.get("kind")
1137        this = f" {self.sql(expression, 'this')}" if expression.this else ""
1138        for_or_in = expression.args.get("for_or_in")
1139        lock_type = expression.args.get("lock_type")
1140        override = " OVERRIDE" if expression.args.get("override") else ""
1141        return f"LOCKING {kind}{this} {for_or_in} {lock_type}{override}"
1142
1143    def withdataproperty_sql(self, expression: exp.WithDataProperty) -> str:
1144        data_sql = f"WITH {'NO ' if expression.args.get('no') else ''}DATA"
1145        statistics = expression.args.get("statistics")
1146        statistics_sql = ""
1147        if statistics is not None:
1148            statistics_sql = f" AND {'NO ' if not statistics else ''}STATISTICS"
1149        return f"{data_sql}{statistics_sql}"
1150
1151    def insert_sql(self, expression: exp.Insert) -> str:
1152        overwrite = expression.args.get("overwrite")
1153
1154        if isinstance(expression.this, exp.Directory):
1155            this = " OVERWRITE" if overwrite else " INTO"
1156        else:
1157            this = " OVERWRITE TABLE" if overwrite else " INTO"
1158
1159        alternative = expression.args.get("alternative")
1160        alternative = f" OR {alternative}" if alternative else ""
1161        ignore = " IGNORE" if expression.args.get("ignore") else ""
1162
1163        this = f"{this} {self.sql(expression, 'this')}"
1164
1165        exists = " IF EXISTS" if expression.args.get("exists") else ""
1166        partition_sql = (
1167            f" {self.sql(expression, 'partition')}" if expression.args.get("partition") else ""
1168        )
1169        where = self.sql(expression, "where")
1170        where = f"{self.sep()}REPLACE WHERE {where}" if where else ""
1171        expression_sql = f"{self.sep()}{self.sql(expression, 'expression')}"
1172        conflict = self.sql(expression, "conflict")
1173        returning = self.sql(expression, "returning")
1174
1175        if self.RETURNING_END:
1176            expression_sql = f"{expression_sql}{conflict}{returning}"
1177        else:
1178            expression_sql = f"{returning}{expression_sql}{conflict}"
1179
1180        sql = f"INSERT{alternative}{ignore}{this}{exists}{partition_sql}{where}{expression_sql}"
1181        return self.prepend_ctes(expression, sql)
1182
1183    def intersect_sql(self, expression: exp.Intersect) -> str:
1184        return self.prepend_ctes(
1185            expression,
1186            self.set_operation(expression, self.intersect_op(expression)),
1187        )
1188
1189    def intersect_op(self, expression: exp.Intersect) -> str:
1190        return f"INTERSECT{'' if expression.args.get('distinct') else ' ALL'}"
1191
1192    def introducer_sql(self, expression: exp.Introducer) -> str:
1193        return f"{self.sql(expression, 'this')} {self.sql(expression, 'expression')}"
1194
1195    def pseudotype_sql(self, expression: exp.PseudoType) -> str:
1196        return expression.name.upper()
1197
1198    def onconflict_sql(self, expression: exp.OnConflict) -> str:
1199        conflict = "ON DUPLICATE KEY" if expression.args.get("duplicate") else "ON CONFLICT"
1200        constraint = self.sql(expression, "constraint")
1201        if constraint:
1202            constraint = f"ON CONSTRAINT {constraint}"
1203        key = self.expressions(expression, key="key", flat=True)
1204        do = "" if expression.args.get("duplicate") else " DO "
1205        nothing = "NOTHING" if expression.args.get("nothing") else ""
1206        expressions = self.expressions(expression, flat=True)
1207        set_keyword = "SET " if self.DUPLICATE_KEY_UPDATE_WITH_SET else ""
1208        if expressions:
1209            expressions = f"UPDATE {set_keyword}{expressions}"
1210        return f"{self.seg(conflict)} {constraint}{key}{do}{nothing}{expressions}"
1211
1212    def returning_sql(self, expression: exp.Returning) -> str:
1213        return f"{self.seg('RETURNING')} {self.expressions(expression, flat=True)}"
1214
1215    def rowformatdelimitedproperty_sql(self, expression: exp.RowFormatDelimitedProperty) -> str:
1216        fields = expression.args.get("fields")
1217        fields = f" FIELDS TERMINATED BY {fields}" if fields else ""
1218        escaped = expression.args.get("escaped")
1219        escaped = f" ESCAPED BY {escaped}" if escaped else ""
1220        items = expression.args.get("collection_items")
1221        items = f" COLLECTION ITEMS TERMINATED BY {items}" if items else ""
1222        keys = expression.args.get("map_keys")
1223        keys = f" MAP KEYS TERMINATED BY {keys}" if keys else ""
1224        lines = expression.args.get("lines")
1225        lines = f" LINES TERMINATED BY {lines}" if lines else ""
1226        null = expression.args.get("null")
1227        null = f" NULL DEFINED AS {null}" if null else ""
1228        return f"ROW FORMAT DELIMITED{fields}{escaped}{items}{keys}{lines}{null}"
1229
1230    def withtablehint_sql(self, expression: exp.WithTableHint) -> str:
1231        return f"WITH ({self.expressions(expression, flat=True)})"
1232
1233    def indextablehint_sql(self, expression: exp.IndexTableHint) -> str:
1234        this = f"{self.sql(expression, 'this')} INDEX"
1235        target = self.sql(expression, "target")
1236        target = f" FOR {target}" if target else ""
1237        return f"{this}{target} ({self.expressions(expression, flat=True)})"
1238
1239    def table_sql(self, expression: exp.Table, sep: str = " AS ") -> str:
1240        table = ".".join(
1241            part
1242            for part in [
1243                self.sql(expression, "catalog"),
1244                self.sql(expression, "db"),
1245                self.sql(expression, "this"),
1246            ]
1247            if part
1248        )
1249
1250        alias = self.sql(expression, "alias")
1251        alias = f"{sep}{alias}" if alias else ""
1252        hints = self.expressions(expression, key="hints", sep=" ")
1253        hints = f" {hints}" if hints and self.TABLE_HINTS else ""
1254        pivots = self.expressions(expression, key="pivots", sep=" ", flat=True)
1255        pivots = f" {pivots}" if pivots else ""
1256        joins = self.expressions(expression, key="joins", sep="", skip_first=True)
1257        laterals = self.expressions(expression, key="laterals", sep="")
1258        system_time = expression.args.get("system_time")
1259        system_time = f" {self.sql(expression, 'system_time')}" if system_time else ""
1260
1261        return f"{table}{system_time}{alias}{hints}{pivots}{joins}{laterals}"
1262
1263    def tablesample_sql(
1264        self, expression: exp.TableSample, seed_prefix: str = "SEED", sep=" AS "
1265    ) -> str:
1266        if self.ALIAS_POST_TABLESAMPLE and expression.this.alias:
1267            table = expression.this.copy()
1268            table.set("alias", None)
1269            this = self.sql(table)
1270            alias = f"{sep}{self.sql(expression.this, 'alias')}"
1271        else:
1272            this = self.sql(expression, "this")
1273            alias = ""
1274        method = self.sql(expression, "method")
1275        method = f"{method.upper()} " if method and self.TABLESAMPLE_WITH_METHOD else ""
1276        numerator = self.sql(expression, "bucket_numerator")
1277        denominator = self.sql(expression, "bucket_denominator")
1278        field = self.sql(expression, "bucket_field")
1279        field = f" ON {field}" if field else ""
1280        bucket = f"BUCKET {numerator} OUT OF {denominator}{field}" if numerator else ""
1281        percent = self.sql(expression, "percent")
1282        percent = f"{percent} PERCENT" if percent else ""
1283        rows = self.sql(expression, "rows")
1284        rows = f"{rows} ROWS" if rows else ""
1285        size = self.sql(expression, "size")
1286        if size and self.TABLESAMPLE_SIZE_IS_PERCENT:
1287            size = f"{size} PERCENT"
1288        seed = self.sql(expression, "seed")
1289        seed = f" {seed_prefix} ({seed})" if seed else ""
1290        kind = expression.args.get("kind", "TABLESAMPLE")
1291        return f"{this} {kind} {method}({bucket}{percent}{rows}{size}){seed}{alias}"
1292
1293    def pivot_sql(self, expression: exp.Pivot) -> str:
1294        expressions = self.expressions(expression, flat=True)
1295
1296        if expression.this:
1297            this = self.sql(expression, "this")
1298            on = f"{self.seg('ON')} {expressions}"
1299            using = self.expressions(expression, key="using", flat=True)
1300            using = f"{self.seg('USING')} {using}" if using else ""
1301            group = self.sql(expression, "group")
1302            return f"PIVOT {this}{on}{using}{group}"
1303
1304        alias = self.sql(expression, "alias")
1305        alias = f" AS {alias}" if alias else ""
1306        unpivot = expression.args.get("unpivot")
1307        direction = "UNPIVOT" if unpivot else "PIVOT"
1308        field = self.sql(expression, "field")
1309        return f"{direction}({expressions} FOR {field}){alias}"
1310
1311    def tuple_sql(self, expression: exp.Tuple) -> str:
1312        return f"({self.expressions(expression, flat=True)})"
1313
1314    def update_sql(self, expression: exp.Update) -> str:
1315        this = self.sql(expression, "this")
1316        set_sql = self.expressions(expression, flat=True)
1317        from_sql = self.sql(expression, "from")
1318        where_sql = self.sql(expression, "where")
1319        returning = self.sql(expression, "returning")
1320        limit = self.sql(expression, "limit")
1321        if self.RETURNING_END:
1322            expression_sql = f"{from_sql}{where_sql}{returning}{limit}"
1323        else:
1324            expression_sql = f"{returning}{from_sql}{where_sql}{limit}"
1325        sql = f"UPDATE {this} SET {set_sql}{expression_sql}"
1326        return self.prepend_ctes(expression, sql)
1327
1328    def values_sql(self, expression: exp.Values) -> str:
1329        # The VALUES clause is still valid in an `INSERT INTO ..` statement, for example
1330        if self.VALUES_AS_TABLE or not expression.find_ancestor(exp.From, exp.Join):
1331            args = self.expressions(expression)
1332            alias = self.sql(expression, "alias")
1333            values = f"VALUES{self.seg('')}{args}"
1334            values = (
1335                f"({values})"
1336                if self.WRAP_DERIVED_VALUES and (alias or isinstance(expression.parent, exp.From))
1337                else values
1338            )
1339            return f"{values} AS {alias}" if alias else values
1340
1341        # Converts `VALUES...` expression into a series of select unions.
1342        # Note: If you have a lot of unions then this will result in a large number of recursive statements to
1343        # evaluate the expression. You may need to increase `sys.setrecursionlimit` to run and it can also be
1344        # very slow.
1345        expression = expression.copy()
1346        column_names = expression.alias and expression.args["alias"].columns
1347
1348        selects = []
1349
1350        for i, tup in enumerate(expression.expressions):
1351            row = tup.expressions
1352
1353            if i == 0 and column_names:
1354                row = [
1355                    exp.alias_(value, column_name) for value, column_name in zip(row, column_names)
1356                ]
1357
1358            selects.append(exp.Select(expressions=row))
1359
1360        subquery_expression: exp.Select | exp.Union = selects[0]
1361        if len(selects) > 1:
1362            for select in selects[1:]:
1363                subquery_expression = exp.union(
1364                    subquery_expression, select, distinct=False, copy=False
1365                )
1366
1367        return self.subquery_sql(subquery_expression.subquery(expression.alias, copy=False))
1368
1369    def var_sql(self, expression: exp.Var) -> str:
1370        return self.sql(expression, "this")
1371
1372    def into_sql(self, expression: exp.Into) -> str:
1373        temporary = " TEMPORARY" if expression.args.get("temporary") else ""
1374        unlogged = " UNLOGGED" if expression.args.get("unlogged") else ""
1375        return f"{self.seg('INTO')}{temporary or unlogged} {self.sql(expression, 'this')}"
1376
1377    def from_sql(self, expression: exp.From) -> str:
1378        return f"{self.seg('FROM')} {self.sql(expression, 'this')}"
1379
1380    def group_sql(self, expression: exp.Group) -> str:
1381        group_by = self.op_expressions("GROUP BY", expression)
1382
1383        if expression.args.get("all"):
1384            return f"{group_by} ALL"
1385
1386        grouping_sets = self.expressions(expression, key="grouping_sets", indent=False)
1387        grouping_sets = (
1388            f"{self.seg('GROUPING SETS')} {self.wrap(grouping_sets)}" if grouping_sets else ""
1389        )
1390
1391        cube = expression.args.get("cube", [])
1392        if seq_get(cube, 0) is True:
1393            return f"{group_by}{self.seg('WITH CUBE')}"
1394        else:
1395            cube_sql = self.expressions(expression, key="cube", indent=False)
1396            cube_sql = f"{self.seg('CUBE')} {self.wrap(cube_sql)}" if cube_sql else ""
1397
1398        rollup = expression.args.get("rollup", [])
1399        if seq_get(rollup, 0) is True:
1400            return f"{group_by}{self.seg('WITH ROLLUP')}"
1401        else:
1402            rollup_sql = self.expressions(expression, key="rollup", indent=False)
1403            rollup_sql = f"{self.seg('ROLLUP')} {self.wrap(rollup_sql)}" if rollup_sql else ""
1404
1405        groupings = csv(
1406            grouping_sets,
1407            cube_sql,
1408            rollup_sql,
1409            self.seg("WITH TOTALS") if expression.args.get("totals") else "",
1410            sep=self.GROUPINGS_SEP,
1411        )
1412
1413        if expression.args.get("expressions") and groupings:
1414            group_by = f"{group_by}{self.GROUPINGS_SEP}"
1415
1416        return f"{group_by}{groupings}"
1417
1418    def having_sql(self, expression: exp.Having) -> str:
1419        this = self.indent(self.sql(expression, "this"))
1420        return f"{self.seg('HAVING')}{self.sep()}{this}"
1421
1422    def join_sql(self, expression: exp.Join) -> str:
1423        op_sql = " ".join(
1424            op
1425            for op in (
1426                expression.method,
1427                "GLOBAL" if expression.args.get("global") else None,
1428                expression.side,
1429                expression.kind,
1430                expression.hint if self.JOIN_HINTS else None,
1431            )
1432            if op
1433        )
1434        on_sql = self.sql(expression, "on")
1435        using = expression.args.get("using")
1436
1437        if not on_sql and using:
1438            on_sql = csv(*(self.sql(column) for column in using))
1439
1440        this_sql = self.sql(expression, "this")
1441
1442        if on_sql:
1443            on_sql = self.indent(on_sql, skip_first=True)
1444            space = self.seg(" " * self.pad) if self.pretty else " "
1445            if using:
1446                on_sql = f"{space}USING ({on_sql})"
1447            else:
1448                on_sql = f"{space}ON {on_sql}"
1449        elif not op_sql:
1450            return f", {this_sql}"
1451
1452        op_sql = f"{op_sql} JOIN" if op_sql else "JOIN"
1453        return f"{self.seg(op_sql)} {this_sql}{on_sql}"
1454
1455    def lambda_sql(self, expression: exp.Lambda, arrow_sep: str = "->") -> str:
1456        args = self.expressions(expression, flat=True)
1457        args = f"({args})" if len(args.split(",")) > 1 else args
1458        return f"{args} {arrow_sep} {self.sql(expression, 'this')}"
1459
1460    def lateral_sql(self, expression: exp.Lateral) -> str:
1461        this = self.sql(expression, "this")
1462
1463        if isinstance(expression.this, exp.Subquery):
1464            return f"LATERAL {this}"
1465
1466        if expression.args.get("view"):
1467            alias = expression.args["alias"]
1468            columns = self.expressions(alias, key="columns", flat=True)
1469            table = f" {alias.name}" if alias.name else ""
1470            columns = f" AS {columns}" if columns else ""
1471            op_sql = self.seg(f"LATERAL VIEW{' OUTER' if expression.args.get('outer') else ''}")
1472            return f"{op_sql}{self.sep()}{this}{table}{columns}"
1473
1474        alias = self.sql(expression, "alias")
1475        alias = f" AS {alias}" if alias else ""
1476        return f"LATERAL {this}{alias}"
1477
1478    def limit_sql(self, expression: exp.Limit, top: bool = False) -> str:
1479        this = self.sql(expression, "this")
1480        args = ", ".join(
1481            sql
1482            for sql in (
1483                self.sql(expression, "offset"),
1484                self.sql(expression, "expression"),
1485            )
1486            if sql
1487        )
1488        return f"{this}{self.seg('TOP' if top else 'LIMIT')} {args}"
1489
1490    def offset_sql(self, expression: exp.Offset) -> str:
1491        this = self.sql(expression, "this")
1492        return f"{this}{self.seg('OFFSET')} {self.sql(expression, 'expression')}"
1493
1494    def setitem_sql(self, expression: exp.SetItem) -> str:
1495        kind = self.sql(expression, "kind")
1496        kind = f"{kind} " if kind else ""
1497        this = self.sql(expression, "this")
1498        expressions = self.expressions(expression)
1499        collate = self.sql(expression, "collate")
1500        collate = f" COLLATE {collate}" if collate else ""
1501        global_ = "GLOBAL " if expression.args.get("global") else ""
1502        return f"{global_}{kind}{this}{expressions}{collate}"
1503
1504    def set_sql(self, expression: exp.Set) -> str:
1505        expressions = (
1506            f" {self.expressions(expression, flat=True)}" if expression.expressions else ""
1507        )
1508        tag = " TAG" if expression.args.get("tag") else ""
1509        return f"{'UNSET' if expression.args.get('unset') else 'SET'}{tag}{expressions}"
1510
1511    def pragma_sql(self, expression: exp.Pragma) -> str:
1512        return f"PRAGMA {self.sql(expression, 'this')}"
1513
1514    def lock_sql(self, expression: exp.Lock) -> str:
1515        if not self.LOCKING_READS_SUPPORTED:
1516            self.unsupported("Locking reads using 'FOR UPDATE/SHARE' are not supported")
1517            return ""
1518
1519        lock_type = "FOR UPDATE" if expression.args["update"] else "FOR SHARE"
1520        expressions = self.expressions(expression, flat=True)
1521        expressions = f" OF {expressions}" if expressions else ""
1522        wait = expression.args.get("wait")
1523
1524        if wait is not None:
1525            if isinstance(wait, exp.Literal):
1526                wait = f" WAIT {self.sql(wait)}"
1527            else:
1528                wait = " NOWAIT" if wait else " SKIP LOCKED"
1529
1530        return f"{lock_type}{expressions}{wait or ''}"
1531
1532    def literal_sql(self, expression: exp.Literal) -> str:
1533        text = expression.this or ""
1534        if expression.is_string:
1535            text = f"{self.QUOTE_START}{self.escape_str(text)}{self.QUOTE_END}"
1536        return text
1537
1538    def escape_str(self, text: str) -> str:
1539        text = text.replace(self.QUOTE_END, self._escaped_quote_end)
1540        if self.ESCAPE_LINE_BREAK:
1541            text = text.replace("\n", "\\n")
1542        elif self.pretty:
1543            text = text.replace("\n", self.SENTINEL_LINE_BREAK)
1544        return text
1545
1546    def loaddata_sql(self, expression: exp.LoadData) -> str:
1547        local = " LOCAL" if expression.args.get("local") else ""
1548        inpath = f" INPATH {self.sql(expression, 'inpath')}"
1549        overwrite = " OVERWRITE" if expression.args.get("overwrite") else ""
1550        this = f" INTO TABLE {self.sql(expression, 'this')}"
1551        partition = self.sql(expression, "partition")
1552        partition = f" {partition}" if partition else ""
1553        input_format = self.sql(expression, "input_format")
1554        input_format = f" INPUTFORMAT {input_format}" if input_format else ""
1555        serde = self.sql(expression, "serde")
1556        serde = f" SERDE {serde}" if serde else ""
1557        return f"LOAD DATA{local}{inpath}{overwrite}{this}{partition}{input_format}{serde}"
1558
1559    def null_sql(self, *_) -> str:
1560        return "NULL"
1561
1562    def boolean_sql(self, expression: exp.Boolean) -> str:
1563        return "TRUE" if expression.this else "FALSE"
1564
1565    def order_sql(self, expression: exp.Order, flat: bool = False) -> str:
1566        this = self.sql(expression, "this")
1567        this = f"{this} " if this else this
1568        return self.op_expressions(f"{this}ORDER BY", expression, flat=this or flat)  # type: ignore
1569
1570    def cluster_sql(self, expression: exp.Cluster) -> str:
1571        return self.op_expressions("CLUSTER BY", expression)
1572
1573    def distribute_sql(self, expression: exp.Distribute) -> str:
1574        return self.op_expressions("DISTRIBUTE BY", expression)
1575
1576    def sort_sql(self, expression: exp.Sort) -> str:
1577        return self.op_expressions("SORT BY", expression)
1578
1579    def ordered_sql(self, expression: exp.Ordered) -> str:
1580        desc = expression.args.get("desc")
1581        asc = not desc
1582
1583        nulls_first = expression.args.get("nulls_first")
1584        nulls_last = not nulls_first
1585        nulls_are_large = self.NULL_ORDERING == "nulls_are_large"
1586        nulls_are_small = self.NULL_ORDERING == "nulls_are_small"
1587        nulls_are_last = self.NULL_ORDERING == "nulls_are_last"
1588
1589        sort_order = " DESC" if desc else ""
1590        nulls_sort_change = ""
1591        if nulls_first and (
1592            (asc and nulls_are_large) or (desc and nulls_are_small) or nulls_are_last
1593        ):
1594            nulls_sort_change = " NULLS FIRST"
1595        elif (
1596            nulls_last
1597            and ((asc and nulls_are_small) or (desc and nulls_are_large))
1598            and not nulls_are_last
1599        ):
1600            nulls_sort_change = " NULLS LAST"
1601
1602        if nulls_sort_change and not self.NULL_ORDERING_SUPPORTED:
1603            self.unsupported(
1604                "Sorting in an ORDER BY on NULLS FIRST/NULLS LAST is not supported by this dialect"
1605            )
1606            nulls_sort_change = ""
1607
1608        return f"{self.sql(expression, 'this')}{sort_order}{nulls_sort_change}"
1609
1610    def matchrecognize_sql(self, expression: exp.MatchRecognize) -> str:
1611        partition = self.partition_by_sql(expression)
1612        order = self.sql(expression, "order")
1613        measures = self.expressions(expression, key="measures")
1614        measures = self.seg(f"MEASURES{self.seg(measures)}") if measures else ""
1615        rows = self.sql(expression, "rows")
1616        rows = self.seg(rows) if rows else ""
1617        after = self.sql(expression, "after")
1618        after = self.seg(after) if after else ""
1619        pattern = self.sql(expression, "pattern")
1620        pattern = self.seg(f"PATTERN ({pattern})") if pattern else ""
1621        definition_sqls = [
1622            f"{self.sql(definition, 'alias')} AS {self.sql(definition, 'this')}"
1623            for definition in expression.args.get("define", [])
1624        ]
1625        definitions = self.expressions(sqls=definition_sqls)
1626        define = self.seg(f"DEFINE{self.seg(definitions)}") if definitions else ""
1627        body = "".join(
1628            (
1629                partition,
1630                order,
1631                measures,
1632                rows,
1633                after,
1634                pattern,
1635                define,
1636            )
1637        )
1638        alias = self.sql(expression, "alias")
1639        alias = f" {alias}" if alias else ""
1640        return f"{self.seg('MATCH_RECOGNIZE')} {self.wrap(body)}{alias}"
1641
1642    def query_modifiers(self, expression: exp.Expression, *sqls: str) -> str:
1643        limit: t.Optional[exp.Fetch | exp.Limit] = expression.args.get("limit")
1644
1645        # If the limit is generated as TOP, we need to ensure it's not generated twice
1646        with_offset_limit_modifiers = not isinstance(limit, exp.Limit) or not self.LIMIT_IS_TOP
1647
1648        if self.LIMIT_FETCH == "LIMIT" and isinstance(limit, exp.Fetch):
1649            limit = exp.Limit(expression=limit.args.get("count"))
1650        elif self.LIMIT_FETCH == "FETCH" and isinstance(limit, exp.Limit):
1651            limit = exp.Fetch(direction="FIRST", count=limit.expression)
1652
1653        fetch = isinstance(limit, exp.Fetch)
1654
1655        offset_limit_modifiers = (
1656            self.offset_limit_modifiers(expression, fetch, limit)
1657            if with_offset_limit_modifiers
1658            else []
1659        )
1660
1661        return csv(
1662            *sqls,
1663            *[self.sql(join) for join in expression.args.get("joins") or []],
1664            self.sql(expression, "match"),
1665            *[self.sql(lateral) for lateral in expression.args.get("laterals") or []],
1666            self.sql(expression, "where"),
1667            self.sql(expression, "group"),
1668            self.sql(expression, "having"),
1669            *self.after_having_modifiers(expression),
1670            self.sql(expression, "order"),
1671            *offset_limit_modifiers,
1672            *self.after_limit_modifiers(expression),
1673            sep="",
1674        )
1675
1676    def offset_limit_modifiers(
1677        self, expression: exp.Expression, fetch: bool, limit: t.Optional[exp.Fetch | exp.Limit]
1678    ) -> t.List[str]:
1679        return [
1680            self.sql(expression, "offset") if fetch else self.sql(limit),
1681            self.sql(limit) if fetch else self.sql(expression, "offset"),
1682        ]
1683
1684    def after_having_modifiers(self, expression: exp.Expression) -> t.List[str]:
1685        return [
1686            self.sql(expression, "qualify"),
1687            self.seg("WINDOW ") + self.expressions(expression, key="windows", flat=True)
1688            if expression.args.get("windows")
1689            else "",
1690            self.sql(expression, "distribute"),
1691            self.sql(expression, "sort"),
1692            self.sql(expression, "cluster"),
1693        ]
1694
1695    def after_limit_modifiers(self, expression: exp.Expression) -> t.List[str]:
1696        locks = self.expressions(expression, key="locks", sep=" ")
1697        locks = f" {locks}" if locks else ""
1698        return [locks, self.sql(expression, "sample")]
1699
1700    def select_sql(self, expression: exp.Select) -> str:
1701        hint = self.sql(expression, "hint")
1702        distinct = self.sql(expression, "distinct")
1703        distinct = f" {distinct}" if distinct else ""
1704        kind = self.sql(expression, "kind").upper()
1705        limit = expression.args.get("limit")
1706        top = (
1707            self.limit_sql(limit, top=True)
1708            if isinstance(limit, exp.Limit) and self.LIMIT_IS_TOP
1709            else ""
1710        )
1711
1712        expressions = self.expressions(expression)
1713
1714        if kind:
1715            if kind in self.SELECT_KINDS:
1716                kind = f" AS {kind}"
1717            else:
1718                if kind == "STRUCT":
1719                    expressions = self.expressions(
1720                        sqls=[
1721                            self.sql(
1722                                exp.Struct(
1723                                    expressions=[
1724                                        exp.column(e.output_name).eq(
1725                                            e.this if isinstance(e, exp.Alias) else e
1726                                        )
1727                                        for e in expression.expressions
1728                                    ]
1729                                )
1730                            )
1731                        ]
1732                    )
1733                kind = ""
1734
1735        expressions = f"{self.sep()}{expressions}" if expressions else expressions
1736        sql = self.query_modifiers(
1737            expression,
1738            f"SELECT{top}{hint}{distinct}{kind}{expressions}",
1739            self.sql(expression, "into", comment=False),
1740            self.sql(expression, "from", comment=False),
1741        )
1742        return self.prepend_ctes(expression, sql)
1743
1744    def schema_sql(self, expression: exp.Schema) -> str:
1745        this = self.sql(expression, "this")
1746        this = f"{this} " if this else ""
1747        sql = self.schema_columns_sql(expression)
1748        return f"{this}{sql}"
1749
1750    def schema_columns_sql(self, expression: exp.Schema) -> str:
1751        return f"({self.sep('')}{self.expressions(expression)}{self.seg(')', sep='')}"
1752
1753    def star_sql(self, expression: exp.Star) -> str:
1754        except_ = self.expressions(expression, key="except", flat=True)
1755        except_ = f"{self.seg(self.STAR_MAPPING['except'])} ({except_})" if except_ else ""
1756        replace = self.expressions(expression, key="replace", flat=True)
1757        replace = f"{self.seg(self.STAR_MAPPING['replace'])} ({replace})" if replace else ""
1758        return f"*{except_}{replace}"
1759
1760    def parameter_sql(self, expression: exp.Parameter) -> str:
1761        this = self.sql(expression, "this")
1762        this = f"{{{this}}}" if expression.args.get("wrapped") else f"{this}"
1763        return f"{self.PARAMETER_TOKEN}{this}"
1764
1765    def sessionparameter_sql(self, expression: exp.SessionParameter) -> str:
1766        this = self.sql(expression, "this")
1767        kind = expression.text("kind")
1768        if kind:
1769            kind = f"{kind}."
1770        return f"@@{kind}{this}"
1771
1772    def placeholder_sql(self, expression: exp.Placeholder) -> str:
1773        return f":{expression.name}" if expression.name else "?"
1774
1775    def subquery_sql(self, expression: exp.Subquery, sep: str = " AS ") -> str:
1776        alias = self.sql(expression, "alias")
1777        alias = f"{sep}{alias}" if alias else ""
1778
1779        pivots = self.expressions(expression, key="pivots", sep=" ", flat=True)
1780        pivots = f" {pivots}" if pivots else ""
1781
1782        sql = self.query_modifiers(expression, self.wrap(expression), alias, pivots)
1783        return self.prepend_ctes(expression, sql)
1784
1785    def qualify_sql(self, expression: exp.Qualify) -> str:
1786        this = self.indent(self.sql(expression, "this"))
1787        return f"{self.seg('QUALIFY')}{self.sep()}{this}"
1788
1789    def union_sql(self, expression: exp.Union) -> str:
1790        return self.prepend_ctes(
1791            expression,
1792            self.set_operation(expression, self.union_op(expression)),
1793        )
1794
1795    def union_op(self, expression: exp.Union) -> str:
1796        kind = " DISTINCT" if self.EXPLICIT_UNION else ""
1797        kind = kind if expression.args.get("distinct") else " ALL"
1798        return f"UNION{kind}"
1799
1800    def unnest_sql(self, expression: exp.Unnest) -> str:
1801        args = self.expressions(expression, flat=True)
1802        alias = expression.args.get("alias")
1803        if alias and self.UNNEST_COLUMN_ONLY:
1804            columns = alias.columns
1805            alias = self.sql(columns[0]) if columns else ""
1806        else:
1807            alias = self.sql(expression, "alias")
1808        alias = f" AS {alias}" if alias else alias
1809        ordinality = " WITH ORDINALITY" if expression.args.get("ordinality") else ""
1810        offset = expression.args.get("offset")
1811        offset = f" WITH OFFSET AS {self.sql(offset)}" if offset else ""
1812        return f"UNNEST({args}){ordinality}{alias}{offset}"
1813
1814    def where_sql(self, expression: exp.Where) -> str:
1815        this = self.indent(self.sql(expression, "this"))
1816        return f"{self.seg('WHERE')}{self.sep()}{this}"
1817
1818    def window_sql(self, expression: exp.Window) -> str:
1819        this = self.sql(expression, "this")
1820        partition = self.partition_by_sql(expression)
1821        order = expression.args.get("order")
1822        order = self.order_sql(order, flat=True) if order else ""
1823        spec = self.sql(expression, "spec")
1824        alias = self.sql(expression, "alias")
1825        over = self.sql(expression, "over") or "OVER"
1826
1827        this = f"{this} {'AS' if expression.arg_key == 'windows' else over}"
1828
1829        first = expression.args.get("first")
1830        if first is None:
1831            first = ""
1832        else:
1833            first = "FIRST" if first else "LAST"
1834
1835        if not partition and not order and not spec and alias:
1836            return f"{this} {alias}"
1837
1838        args = " ".join(arg for arg in (alias, first, partition, order, spec) if arg)
1839        return f"{this} ({args})"
1840
1841    def partition_by_sql(self, expression: exp.Window | exp.MatchRecognize) -> str:
1842        partition = self.expressions(expression, key="partition_by", flat=True)
1843        return f"PARTITION BY {partition}" if partition else ""
1844
1845    def windowspec_sql(self, expression: exp.WindowSpec) -> str:
1846        kind = self.sql(expression, "kind")
1847        start = csv(self.sql(expression, "start"), self.sql(expression, "start_side"), sep=" ")
1848        end = (
1849            csv(self.sql(expression, "end"), self.sql(expression, "end_side"), sep=" ")
1850            or "CURRENT ROW"
1851        )
1852        return f"{kind} BETWEEN {start} AND {end}"
1853
1854    def withingroup_sql(self, expression: exp.WithinGroup) -> str:
1855        this = self.sql(expression, "this")
1856        expression_sql = self.sql(expression, "expression")[1:]  # order has a leading space
1857        return f"{this} WITHIN GROUP ({expression_sql})"
1858
1859    def between_sql(self, expression: exp.Between) -> str:
1860        this = self.sql(expression, "this")
1861        low = self.sql(expression, "low")
1862        high = self.sql(expression, "high")
1863        return f"{this} BETWEEN {low} AND {high}"
1864
1865    def bracket_sql(self, expression: exp.Bracket) -> str:
1866        expressions = apply_index_offset(expression.this, expression.expressions, self.INDEX_OFFSET)
1867        expressions_sql = ", ".join(self.sql(e) for e in expressions)
1868
1869        return f"{self.sql(expression, 'this')}[{expressions_sql}]"
1870
1871    def safebracket_sql(self, expression: exp.SafeBracket) -> str:
1872        return self.bracket_sql(expression)
1873
1874    def all_sql(self, expression: exp.All) -> str:
1875        return f"ALL {self.wrap(expression)}"
1876
1877    def any_sql(self, expression: exp.Any) -> str:
1878        this = self.sql(expression, "this")
1879        if isinstance(expression.this, exp.Subqueryable):
1880            this = self.wrap(this)
1881        return f"ANY {this}"
1882
1883    def exists_sql(self, expression: exp.Exists) -> str:
1884        return f"EXISTS{self.wrap(expression)}"
1885
1886    def case_sql(self, expression: exp.Case) -> str:
1887        this = self.sql(expression, "this")
1888        statements = [f"CASE {this}" if this else "CASE"]
1889
1890        for e in expression.args["ifs"]:
1891            statements.append(f"WHEN {self.sql(e, 'this')}")
1892            statements.append(f"THEN {self.sql(e, 'true')}")
1893
1894        default = self.sql(expression, "default")
1895
1896        if default:
1897            statements.append(f"ELSE {default}")
1898
1899        statements.append("END")
1900
1901        if self.pretty and self.text_width(statements) > self.max_text_width:
1902            return self.indent("\n".join(statements), skip_first=True, skip_last=True)
1903
1904        return " ".join(statements)
1905
1906    def constraint_sql(self, expression: exp.Constraint) -> str:
1907        this = self.sql(expression, "this")
1908        expressions = self.expressions(expression, flat=True)
1909        return f"CONSTRAINT {this} {expressions}"
1910
1911    def nextvaluefor_sql(self, expression: exp.NextValueFor) -> str:
1912        order = expression.args.get("order")
1913        order = f" OVER ({self.order_sql(order, flat=True)})" if order else ""
1914        return f"NEXT VALUE FOR {self.sql(expression, 'this')}{order}"
1915
1916    def extract_sql(self, expression: exp.Extract) -> str:
1917        this = self.sql(expression, "this") if self.EXTRACT_ALLOWS_QUOTES else expression.this.name
1918        expression_sql = self.sql(expression, "expression")
1919        return f"EXTRACT({this} FROM {expression_sql})"
1920
1921    def trim_sql(self, expression: exp.Trim) -> str:
1922        trim_type = self.sql(expression, "position")
1923
1924        if trim_type == "LEADING":
1925            return self.func("LTRIM", expression.this)
1926        elif trim_type == "TRAILING":
1927            return self.func("RTRIM", expression.this)
1928        else:
1929            return self.func("TRIM", expression.this, expression.expression)
1930
1931    def safeconcat_sql(self, expression: exp.SafeConcat) -> str:
1932        expressions = expression.expressions
1933        if self.STRICT_STRING_CONCAT:
1934            expressions = (exp.cast(e, "text") for e in expressions)
1935        return self.func("CONCAT", *expressions)
1936
1937    def check_sql(self, expression: exp.Check) -> str:
1938        this = self.sql(expression, key="this")
1939        return f"CHECK ({this})"
1940
1941    def foreignkey_sql(self, expression: exp.ForeignKey) -> str:
1942        expressions = self.expressions(expression, flat=True)
1943        reference = self.sql(expression, "reference")
1944        reference = f" {reference}" if reference else ""
1945        delete = self.sql(expression, "delete")
1946        delete = f" ON DELETE {delete}" if delete else ""
1947        update = self.sql(expression, "update")
1948        update = f" ON UPDATE {update}" if update else ""
1949        return f"FOREIGN KEY ({expressions}){reference}{delete}{update}"
1950
1951    def primarykey_sql(self, expression: exp.ForeignKey) -> str:
1952        expressions = self.expressions(expression, flat=True)
1953        options = self.expressions(expression, key="options", flat=True, sep=" ")
1954        options = f" {options}" if options else ""
1955        return f"PRIMARY KEY ({expressions}){options}"
1956
1957    def if_sql(self, expression: exp.If) -> str:
1958        return self.case_sql(exp.Case(ifs=[expression], default=expression.args.get("false")))
1959
1960    def matchagainst_sql(self, expression: exp.MatchAgainst) -> str:
1961        modifier = expression.args.get("modifier")
1962        modifier = f" {modifier}" if modifier else ""
1963        return f"{self.func('MATCH', *expression.expressions)} AGAINST({self.sql(expression, 'this')}{modifier})"
1964
1965    def jsonkeyvalue_sql(self, expression: exp.JSONKeyValue) -> str:
1966        return f"{self.sql(expression, 'this')}: {self.sql(expression, 'expression')}"
1967
1968    def jsonobject_sql(self, expression: exp.JSONObject) -> str:
1969        null_handling = expression.args.get("null_handling")
1970        null_handling = f" {null_handling}" if null_handling else ""
1971        unique_keys = expression.args.get("unique_keys")
1972        if unique_keys is not None:
1973            unique_keys = f" {'WITH' if unique_keys else 'WITHOUT'} UNIQUE KEYS"
1974        else:
1975            unique_keys = ""
1976        return_type = self.sql(expression, "return_type")
1977        return_type = f" RETURNING {return_type}" if return_type else ""
1978        format_json = " FORMAT JSON" if expression.args.get("format_json") else ""
1979        encoding = self.sql(expression, "encoding")
1980        encoding = f" ENCODING {encoding}" if encoding else ""
1981        return self.func(
1982            "JSON_OBJECT",
1983            *expression.expressions,
1984            suffix=f"{null_handling}{unique_keys}{return_type}{format_json}{encoding})",
1985        )
1986
1987    def openjsoncolumndef_sql(self, expression: exp.OpenJSONColumnDef) -> str:
1988        this = self.sql(expression, "this")
1989        kind = self.sql(expression, "kind")
1990        path = self.sql(expression, "path")
1991        path = f" {path}" if path else ""
1992        as_json = " AS JSON" if expression.args.get("as_json") else ""
1993        return f"{this} {kind}{path}{as_json}"
1994
1995    def openjson_sql(self, expression: exp.OpenJSON) -> str:
1996        this = self.sql(expression, "this")
1997        path = self.sql(expression, "path")
1998        path = f", {path}" if path else ""
1999        expressions = self.expressions(expression)
2000        with_ = (
2001            f" WITH ({self.seg(self.indent(expressions), sep='')}{self.seg(')', sep='')}"
2002            if expressions
2003            else ""
2004        )
2005        return f"OPENJSON({this}{path}){with_}"
2006
2007    def in_sql(self, expression: exp.In) -> str:
2008        query = expression.args.get("query")
2009        unnest = expression.args.get("unnest")
2010        field = expression.args.get("field")
2011        is_global = " GLOBAL" if expression.args.get("is_global") else ""
2012
2013        if query:
2014            in_sql = self.wrap(query)
2015        elif unnest:
2016            in_sql = self.in_unnest_op(unnest)
2017        elif field:
2018            in_sql = self.sql(field)
2019        else:
2020            in_sql = f"({self.expressions(expression, flat=True)})"
2021
2022        return f"{self.sql(expression, 'this')}{is_global} IN {in_sql}"
2023
2024    def in_unnest_op(self, unnest: exp.Unnest) -> str:
2025        return f"(SELECT {self.sql(unnest)})"
2026
2027    def interval_sql(self, expression: exp.Interval) -> str:
2028        unit = self.sql(expression, "unit")
2029        if not self.INTERVAL_ALLOWS_PLURAL_FORM:
2030            unit = self.TIME_PART_SINGULARS.get(unit.lower(), unit)
2031        unit = f" {unit}" if unit else ""
2032
2033        if self.SINGLE_STRING_INTERVAL:
2034            this = expression.this.name if expression.this else ""
2035            return f"INTERVAL '{this}{unit}'" if this else f"INTERVAL{unit}"
2036
2037        this = self.sql(expression, "this")
2038        if this:
2039            unwrapped = isinstance(expression.this, self.UNWRAPPED_INTERVAL_VALUES)
2040            this = f" {this}" if unwrapped else f" ({this})"
2041
2042        return f"INTERVAL{this}{unit}"
2043
2044    def return_sql(self, expression: exp.Return) -> str:
2045        return f"RETURN {self.sql(expression, 'this')}"
2046
2047    def reference_sql(self, expression: exp.Reference) -> str:
2048        this = self.sql(expression, "this")
2049        expressions = self.expressions(expression, flat=True)
2050        expressions = f"({expressions})" if expressions else ""
2051        options = self.expressions(expression, key="options", flat=True, sep=" ")
2052        options = f" {options}" if options else ""
2053        return f"REFERENCES {this}{expressions}{options}"
2054
2055    def anonymous_sql(self, expression: exp.Anonymous) -> str:
2056        return self.func(expression.name, *expression.expressions)
2057
2058    def paren_sql(self, expression: exp.Paren) -> str:
2059        if isinstance(expression.unnest(), exp.Select):
2060            sql = self.wrap(expression)
2061        else:
2062            sql = self.seg(self.indent(self.sql(expression, "this")), sep="")
2063            sql = f"({sql}{self.seg(')', sep='')}"
2064
2065        return self.prepend_ctes(expression, sql)
2066
2067    def neg_sql(self, expression: exp.Neg) -> str:
2068        # This makes sure we don't convert "- - 5" to "--5", which is a comment
2069        this_sql = self.sql(expression, "this")
2070        sep = " " if this_sql[0] == "-" else ""
2071        return f"-{sep}{this_sql}"
2072
2073    def not_sql(self, expression: exp.Not) -> str:
2074        return f"NOT {self.sql(expression, 'this')}"
2075
2076    def alias_sql(self, expression: exp.Alias) -> str:
2077        alias = self.sql(expression, "alias")
2078        alias = f" AS {alias}" if alias else ""
2079        return f"{self.sql(expression, 'this')}{alias}"
2080
2081    def aliases_sql(self, expression: exp.Aliases) -> str:
2082        return f"{self.sql(expression, 'this')} AS ({self.expressions(expression, flat=True)})"
2083
2084    def attimezone_sql(self, expression: exp.AtTimeZone) -> str:
2085        this = self.sql(expression, "this")
2086        zone = self.sql(expression, "zone")
2087        return f"{this} AT TIME ZONE {zone}"
2088
2089    def add_sql(self, expression: exp.Add) -> str:
2090        return self.binary(expression, "+")
2091
2092    def and_sql(self, expression: exp.And) -> str:
2093        return self.connector_sql(expression, "AND")
2094
2095    def xor_sql(self, expression: exp.Xor) -> str:
2096        return self.connector_sql(expression, "XOR")
2097
2098    def connector_sql(self, expression: exp.Connector, op: str) -> str:
2099        if not self.pretty:
2100            return self.binary(expression, op)
2101
2102        sqls = tuple(
2103            self.maybe_comment(self.sql(e), e, e.parent.comments or []) if i != 1 else self.sql(e)
2104            for i, e in enumerate(expression.flatten(unnest=False))
2105        )
2106
2107        sep = "\n" if self.text_width(sqls) > self.max_text_width else " "
2108        return f"{sep}{op} ".join(sqls)
2109
2110    def bitwiseand_sql(self, expression: exp.BitwiseAnd) -> str:
2111        return self.binary(expression, "&")
2112
2113    def bitwiseleftshift_sql(self, expression: exp.BitwiseLeftShift) -> str:
2114        return self.binary(expression, "<<")
2115
2116    def bitwisenot_sql(self, expression: exp.BitwiseNot) -> str:
2117        return f"~{self.sql(expression, 'this')}"
2118
2119    def bitwiseor_sql(self, expression: exp.BitwiseOr) -> str:
2120        return self.binary(expression, "|")
2121
2122    def bitwiserightshift_sql(self, expression: exp.BitwiseRightShift) -> str:
2123        return self.binary(expression, ">>")
2124
2125    def bitwisexor_sql(self, expression: exp.BitwiseXor) -> str:
2126        return self.binary(expression, "^")
2127
2128    def cast_sql(self, expression: exp.Cast, safe_prefix: t.Optional[str] = None) -> str:
2129        format_sql = self.sql(expression, "format")
2130        format_sql = f" FORMAT {format_sql}" if format_sql else ""
2131        return f"{safe_prefix or ''}CAST({self.sql(expression, 'this')} AS {self.sql(expression, 'to')}{format_sql})"
2132
2133    def currentdate_sql(self, expression: exp.CurrentDate) -> str:
2134        zone = self.sql(expression, "this")
2135        return f"CURRENT_DATE({zone})" if zone else "CURRENT_DATE"
2136
2137    def collate_sql(self, expression: exp.Collate) -> str:
2138        return self.binary(expression, "COLLATE")
2139
2140    def command_sql(self, expression: exp.Command) -> str:
2141        return f"{self.sql(expression, 'this').upper()} {expression.text('expression').strip()}"
2142
2143    def comment_sql(self, expression: exp.Comment) -> str:
2144        this = self.sql(expression, "this")
2145        kind = expression.args["kind"]
2146        exists_sql = " IF EXISTS " if expression.args.get("exists") else " "
2147        expression_sql = self.sql(expression, "expression")
2148        return f"COMMENT{exists_sql}ON {kind} {this} IS {expression_sql}"
2149
2150    def mergetreettlaction_sql(self, expression: exp.MergeTreeTTLAction) -> str:
2151        this = self.sql(expression, "this")
2152        delete = " DELETE" if expression.args.get("delete") else ""
2153        recompress = self.sql(expression, "recompress")
2154        recompress = f" RECOMPRESS {recompress}" if recompress else ""
2155        to_disk = self.sql(expression, "to_disk")
2156        to_disk = f" TO DISK {to_disk}" if to_disk else ""
2157        to_volume = self.sql(expression, "to_volume")
2158        to_volume = f" TO VOLUME {to_volume}" if to_volume else ""
2159        return f"{this}{delete}{recompress}{to_disk}{to_volume}"
2160
2161    def mergetreettl_sql(self, expression: exp.MergeTreeTTL) -> str:
2162        where = self.sql(expression, "where")
2163        group = self.sql(expression, "group")
2164        aggregates = self.expressions(expression, key="aggregates")
2165        aggregates = self.seg("SET") + self.seg(aggregates) if aggregates else ""
2166
2167        if not (where or group or aggregates) and len(expression.expressions) == 1:
2168            return f"TTL {self.expressions(expression, flat=True)}"
2169
2170        return f"TTL{self.seg(self.expressions(expression))}{where}{group}{aggregates}"
2171
2172    def transaction_sql(self, expression: exp.Transaction) -> str:
2173        return "BEGIN"
2174
2175    def commit_sql(self, expression: exp.Commit) -> str:
2176        chain = expression.args.get("chain")
2177        if chain is not None:
2178            chain = " AND CHAIN" if chain else " AND NO CHAIN"
2179
2180        return f"COMMIT{chain or ''}"
2181
2182    def rollback_sql(self, expression: exp.Rollback) -> str:
2183        savepoint = expression.args.get("savepoint")
2184        savepoint = f" TO {savepoint}" if savepoint else ""
2185        return f"ROLLBACK{savepoint}"
2186
2187    def altercolumn_sql(self, expression: exp.AlterColumn) -> str:
2188        this = self.sql(expression, "this")
2189
2190        dtype = self.sql(expression, "dtype")
2191        if dtype:
2192            collate = self.sql(expression, "collate")
2193            collate = f" COLLATE {collate}" if collate else ""
2194            using = self.sql(expression, "using")
2195            using = f" USING {using}" if using else ""
2196            return f"ALTER COLUMN {this} TYPE {dtype}{collate}{using}"
2197
2198        default = self.sql(expression, "default")
2199        if default:
2200            return f"ALTER COLUMN {this} SET DEFAULT {default}"
2201
2202        if not expression.args.get("drop"):
2203            self.unsupported("Unsupported ALTER COLUMN syntax")
2204
2205        return f"ALTER COLUMN {this} DROP DEFAULT"
2206
2207    def renametable_sql(self, expression: exp.RenameTable) -> str:
2208        if not self.RENAME_TABLE_WITH_DB:
2209            # Remove db from tables
2210            expression = expression.transform(
2211                lambda n: exp.table_(n.this) if isinstance(n, exp.Table) else n
2212            )
2213        this = self.sql(expression, "this")
2214        return f"RENAME TO {this}"
2215
2216    def altertable_sql(self, expression: exp.AlterTable) -> str:
2217        actions = expression.args["actions"]
2218
2219        if isinstance(actions[0], exp.ColumnDef):
2220            actions = self.expressions(expression, key="actions", prefix="ADD COLUMN ")
2221        elif isinstance(actions[0], exp.Schema):
2222            actions = self.expressions(expression, key="actions", prefix="ADD COLUMNS ")
2223        elif isinstance(actions[0], exp.Delete):
2224            actions = self.expressions(expression, key="actions", flat=True)
2225        else:
2226            actions = self.expressions(expression, key="actions")
2227
2228        exists = " IF EXISTS" if expression.args.get("exists") else ""
2229        return f"ALTER TABLE{exists} {self.sql(expression, 'this')} {actions}"
2230
2231    def droppartition_sql(self, expression: exp.DropPartition) -> str:
2232        expressions = self.expressions(expression)
2233        exists = " IF EXISTS " if expression.args.get("exists") else " "
2234        return f"DROP{exists}{expressions}"
2235
2236    def addconstraint_sql(self, expression: exp.AddConstraint) -> str:
2237        this = self.sql(expression, "this")
2238        expression_ = self.sql(expression, "expression")
2239        add_constraint = f"ADD CONSTRAINT {this}" if this else "ADD"
2240
2241        enforced = expression.args.get("enforced")
2242        if enforced is not None:
2243            return f"{add_constraint} CHECK ({expression_}){' ENFORCED' if enforced else ''}"
2244
2245        return f"{add_constraint} {expression_}"
2246
2247    def distinct_sql(self, expression: exp.Distinct) -> str:
2248        this = self.expressions(expression, flat=True)
2249        this = f" {this}" if this else ""
2250
2251        on = self.sql(expression, "on")
2252        on = f" ON {on}" if on else ""
2253        return f"DISTINCT{this}{on}"
2254
2255    def ignorenulls_sql(self, expression: exp.IgnoreNulls) -> str:
2256        return f"{self.sql(expression, 'this')} IGNORE NULLS"
2257
2258    def respectnulls_sql(self, expression: exp.RespectNulls) -> str:
2259        return f"{self.sql(expression, 'this')} RESPECT NULLS"
2260
2261    def intdiv_sql(self, expression: exp.IntDiv) -> str:
2262        return self.sql(
2263            exp.Cast(
2264                this=exp.Div(this=expression.this, expression=expression.expression),
2265                to=exp.DataType(this=exp.DataType.Type.INT),
2266            )
2267        )
2268
2269    def dpipe_sql(self, expression: exp.DPipe) -> str:
2270        return self.binary(expression, "||")
2271
2272    def safedpipe_sql(self, expression: exp.SafeDPipe) -> str:
2273        if self.STRICT_STRING_CONCAT:
2274            return self.func("CONCAT", *(exp.cast(e, "text") for e in expression.flatten()))
2275        return self.dpipe_sql(expression)
2276
2277    def div_sql(self, expression: exp.Div) -> str:
2278        return self.binary(expression, "/")
2279
2280    def overlaps_sql(self, expression: exp.Overlaps) -> str:
2281        return self.binary(expression, "OVERLAPS")
2282
2283    def distance_sql(self, expression: exp.Distance) -> str:
2284        return self.binary(expression, "<->")
2285
2286    def dot_sql(self, expression: exp.Dot) -> str:
2287        return f"{self.sql(expression, 'this')}.{self.sql(expression, 'expression')}"
2288
2289    def eq_sql(self, expression: exp.EQ) -> str:
2290        return self.binary(expression, "=")
2291
2292    def escape_sql(self, expression: exp.Escape) -> str:
2293        return self.binary(expression, "ESCAPE")
2294
2295    def glob_sql(self, expression: exp.Glob) -> str:
2296        return self.binary(expression, "GLOB")
2297
2298    def gt_sql(self, expression: exp.GT) -> str:
2299        return self.binary(expression, ">")
2300
2301    def gte_sql(self, expression: exp.GTE) -> str:
2302        return self.binary(expression, ">=")
2303
2304    def ilike_sql(self, expression: exp.ILike) -> str:
2305        return self.binary(expression, "ILIKE")
2306
2307    def ilikeany_sql(self, expression: exp.ILikeAny) -> str:
2308        return self.binary(expression, "ILIKE ANY")
2309
2310    def is_sql(self, expression: exp.Is) -> str:
2311        if not self.IS_BOOL_ALLOWED and isinstance(expression.expression, exp.Boolean):
2312            return self.sql(
2313                expression.this if expression.expression.this else exp.not_(expression.this)
2314            )
2315        return self.binary(expression, "IS")
2316
2317    def like_sql(self, expression: exp.Like) -> str:
2318        return self.binary(expression, "LIKE")
2319
2320    def likeany_sql(self, expression: exp.LikeAny) -> str:
2321        return self.binary(expression, "LIKE ANY")
2322
2323    def similarto_sql(self, expression: exp.SimilarTo) -> str:
2324        return self.binary(expression, "SIMILAR TO")
2325
2326    def lt_sql(self, expression: exp.LT) -> str:
2327        return self.binary(expression, "<")
2328
2329    def lte_sql(self, expression: exp.LTE) -> str:
2330        return self.binary(expression, "<=")
2331
2332    def mod_sql(self, expression: exp.Mod) -> str:
2333        return self.binary(expression, "%")
2334
2335    def mul_sql(self, expression: exp.Mul) -> str:
2336        return self.binary(expression, "*")
2337
2338    def neq_sql(self, expression: exp.NEQ) -> str:
2339        return self.binary(expression, "<>")
2340
2341    def nullsafeeq_sql(self, expression: exp.NullSafeEQ) -> str:
2342        return self.binary(expression, "IS NOT DISTINCT FROM")
2343
2344    def nullsafeneq_sql(self, expression: exp.NullSafeNEQ) -> str:
2345        return self.binary(expression, "IS DISTINCT FROM")
2346
2347    def or_sql(self, expression: exp.Or) -> str:
2348        return self.connector_sql(expression, "OR")
2349
2350    def slice_sql(self, expression: exp.Slice) -> str:
2351        return self.binary(expression, ":")
2352
2353    def sub_sql(self, expression: exp.Sub) -> str:
2354        return self.binary(expression, "-")
2355
2356    def trycast_sql(self, expression: exp.TryCast) -> str:
2357        return self.cast_sql(expression, safe_prefix="TRY_")
2358
2359    def use_sql(self, expression: exp.Use) -> str:
2360        kind = self.sql(expression, "kind")
2361        kind = f" {kind}" if kind else ""
2362        this = self.sql(expression, "this")
2363        this = f" {this}" if this else ""
2364        return f"USE{kind}{this}"
2365
2366    def binary(self, expression: exp.Binary, op: str) -> str:
2367        op = self.maybe_comment(op, comments=expression.comments)
2368        return f"{self.sql(expression, 'this')} {op} {self.sql(expression, 'expression')}"
2369
2370    def function_fallback_sql(self, expression: exp.Func) -> str:
2371        args = []
2372
2373        for key in expression.arg_types:
2374            arg_value = expression.args.get(key)
2375
2376            if isinstance(arg_value, list):
2377                for value in arg_value:
2378                    args.append(value)
2379            elif arg_value is not None:
2380                args.append(arg_value)
2381
2382        if self.normalize_functions:
2383            name = expression.sql_name()
2384        else:
2385            name = (expression._meta and expression.meta.get("name")) or expression.sql_name()
2386
2387        return self.func(name, *args)
2388
2389    def func(
2390        self,
2391        name: str,
2392        *args: t.Optional[exp.Expression | str],
2393        prefix: str = "(",
2394        suffix: str = ")",
2395    ) -> str:
2396        return f"{self.normalize_func(name)}{prefix}{self.format_args(*args)}{suffix}"
2397
2398    def format_args(self, *args: t.Optional[str | exp.Expression]) -> str:
2399        arg_sqls = tuple(self.sql(arg) for arg in args if arg is not None)
2400        if self.pretty and self.text_width(arg_sqls) > self.max_text_width:
2401            return self.indent("\n" + f",\n".join(arg_sqls) + "\n", skip_first=True, skip_last=True)
2402        return ", ".join(arg_sqls)
2403
2404    def text_width(self, args: t.Iterable) -> int:
2405        return sum(len(arg) for arg in args)
2406
2407    def format_time(self, expression: exp.Expression) -> t.Optional[str]:
2408        return format_time(
2409            self.sql(expression, "format"), self.INVERSE_TIME_MAPPING, self.INVERSE_TIME_TRIE
2410        )
2411
2412    def expressions(
2413        self,
2414        expression: t.Optional[exp.Expression] = None,
2415        key: t.Optional[str] = None,
2416        sqls: t.Optional[t.List[str]] = None,
2417        flat: bool = False,
2418        indent: bool = True,
2419        skip_first: bool = False,
2420        sep: str = ", ",
2421        prefix: str = "",
2422    ) -> str:
2423        expressions = expression.args.get(key or "expressions") if expression else sqls
2424
2425        if not expressions:
2426            return ""
2427
2428        if flat:
2429            return sep.join(sql for sql in (self.sql(e) for e in expressions) if sql)
2430
2431        num_sqls = len(expressions)
2432
2433        # These are calculated once in case we have the leading_comma / pretty option set, correspondingly
2434        pad = " " * self.pad
2435        stripped_sep = sep.strip()
2436
2437        result_sqls = []
2438        for i, e in enumerate(expressions):
2439            sql = self.sql(e, comment=False)
2440            if not sql:
2441                continue
2442
2443            comments = self.maybe_comment("", e) if isinstance(e, exp.Expression) else ""
2444
2445            if self.pretty:
2446                if self.leading_comma:
2447                    result_sqls.append(f"{sep if i > 0 else pad}{prefix}{sql}{comments}")
2448                else:
2449                    result_sqls.append(
2450                        f"{prefix}{sql}{stripped_sep if i + 1 < num_sqls else ''}{comments}"
2451                    )
2452            else:
2453                result_sqls.append(f"{prefix}{sql}{comments}{sep if i + 1 < num_sqls else ''}")
2454
2455        result_sql = "\n".join(result_sqls) if self.pretty else "".join(result_sqls)
2456        return self.indent(result_sql, skip_first=skip_first) if indent else result_sql
2457
2458    def op_expressions(self, op: str, expression: exp.Expression, flat: bool = False) -> str:
2459        flat = flat or isinstance(expression.parent, exp.Properties)
2460        expressions_sql = self.expressions(expression, flat=flat)
2461        if flat:
2462            return f"{op} {expressions_sql}"
2463        return f"{self.seg(op)}{self.sep() if expressions_sql else ''}{expressions_sql}"
2464
2465    def naked_property(self, expression: exp.Property) -> str:
2466        property_name = exp.Properties.PROPERTY_TO_NAME.get(expression.__class__)
2467        if not property_name:
2468            self.unsupported(f"Unsupported property {expression.__class__.__name__}")
2469        return f"{property_name} {self.sql(expression, 'this')}"
2470
2471    def set_operation(self, expression: exp.Expression, op: str) -> str:
2472        this = self.sql(expression, "this")
2473        op = self.seg(op)
2474        return self.query_modifiers(
2475            expression, f"{this}{op}{self.sep()}{self.sql(expression, 'expression')}"
2476        )
2477
2478    def tag_sql(self, expression: exp.Tag) -> str:
2479        return f"{expression.args.get('prefix')}{self.sql(expression.this)}{expression.args.get('postfix')}"
2480
2481    def token_sql(self, token_type: TokenType) -> str:
2482        return self.TOKEN_MAPPING.get(token_type, token_type.name)
2483
2484    def userdefinedfunction_sql(self, expression: exp.UserDefinedFunction) -> str:
2485        this = self.sql(expression, "this")
2486        expressions = self.no_identify(self.expressions, expression)
2487        expressions = (
2488            self.wrap(expressions) if expression.args.get("wrapped") else f" {expressions}"
2489        )
2490        return f"{this}{expressions}"
2491
2492    def joinhint_sql(self, expression: exp.JoinHint) -> str:
2493        this = self.sql(expression, "this")
2494        expressions = self.expressions(expression, flat=True)
2495        return f"{this}({expressions})"
2496
2497    def kwarg_sql(self, expression: exp.Kwarg) -> str:
2498        return self.binary(expression, "=>")
2499
2500    def when_sql(self, expression: exp.When) -> str:
2501        matched = "MATCHED" if expression.args["matched"] else "NOT MATCHED"
2502        source = " BY SOURCE" if self.MATCHED_BY_SOURCE and expression.args.get("source") else ""
2503        condition = self.sql(expression, "condition")
2504        condition = f" AND {condition}" if condition else ""
2505
2506        then_expression = expression.args.get("then")
2507        if isinstance(then_expression, exp.Insert):
2508            then = f"INSERT {self.sql(then_expression, 'this')}"
2509            if "expression" in then_expression.args:
2510                then += f" VALUES {self.sql(then_expression, 'expression')}"
2511        elif isinstance(then_expression, exp.Update):
2512            if isinstance(then_expression.args.get("expressions"), exp.Star):
2513                then = f"UPDATE {self.sql(then_expression, 'expressions')}"
2514            else:
2515                then = f"UPDATE SET {self.expressions(then_expression, flat=True)}"
2516        else:
2517            then = self.sql(then_expression)
2518        return f"WHEN {matched}{source}{condition} THEN {then}"
2519
2520    def merge_sql(self, expression: exp.Merge) -> str:
2521        this = self.sql(expression, "this")
2522        using = f"USING {self.sql(expression, 'using')}"
2523        on = f"ON {self.sql(expression, 'on')}"
2524        return f"MERGE INTO {this} {using} {on} {self.expressions(expression, sep=' ')}"
2525
2526    def tochar_sql(self, expression: exp.ToChar) -> str:
2527        if expression.args.get("format"):
2528            self.unsupported("Format argument unsupported for TO_CHAR/TO_VARCHAR function")
2529
2530        return self.sql(exp.cast(expression.this, "text"))
2531
2532    def dictproperty_sql(self, expression: exp.DictProperty) -> str:
2533        this = self.sql(expression, "this")
2534        kind = self.sql(expression, "kind")
2535        settings_sql = self.expressions(expression, key="settings", sep=" ")
2536        args = f"({self.sep('')}{settings_sql}{self.seg(')', sep='')}" if settings_sql else "()"
2537        return f"{this}({kind}{args})"
2538
2539    def dictrange_sql(self, expression: exp.DictRange) -> str:
2540        this = self.sql(expression, "this")
2541        max = self.sql(expression, "max")
2542        min = self.sql(expression, "min")
2543        return f"{this}(MIN {min} MAX {max})"
2544
2545    def dictsubproperty_sql(self, expression: exp.DictSubProperty) -> str:
2546        return f"{self.sql(expression, 'this')} {self.sql(expression, 'value')}"
2547
2548    def oncluster_sql(self, expression: exp.OnCluster) -> str:
2549        return ""
2550
2551    def clusteredbyproperty_sql(self, expression: exp.ClusteredByProperty) -> str:
2552        expressions = self.expressions(expression, key="expressions", flat=True)
2553        sorted_by = self.expressions(expression, key="sorted_by", flat=True)
2554        sorted_by = f" SORTED BY ({sorted_by})" if sorted_by else ""
2555        buckets = self.sql(expression, "buckets")
2556        return f"CLUSTERED BY ({expressions}){sorted_by} INTO {buckets} BUCKETS"
2557
2558    def anyvalue_sql(self, expression: exp.AnyValue) -> str:
2559        this = self.sql(expression, "this")
2560        having = self.sql(expression, "having")
2561
2562        if having:
2563            this = f"{this} HAVING {'MAX' if expression.args.get('max') else 'MIN'} {having}"
2564
2565        return self.func("ANY_VALUE", this)
2566
2567    def querytransform_sql(self, expression: exp.QueryTransform) -> str:
2568        transform = self.func("TRANSFORM", *expression.expressions)
2569        row_format_before = self.sql(expression, "row_format_before")
2570        row_format_before = f" {row_format_before}" if row_format_before else ""
2571        record_writer = self.sql(expression, "record_writer")
2572        record_writer = f" RECORDWRITER {record_writer}" if record_writer else ""
2573        using = f" USING {self.sql(expression, 'command_script')}"
2574        schema = self.sql(expression, "schema")
2575        schema = f" AS {schema}" if schema else ""
2576        row_format_after = self.sql(expression, "row_format_after")
2577        row_format_after = f" {row_format_after}" if row_format_after else ""
2578        record_reader = self.sql(expression, "record_reader")
2579        record_reader = f" RECORDREADER {record_reader}" if record_reader else ""
2580        return f"{transform}{row_format_before}{record_writer}{using}{schema}{row_format_after}{record_reader}"
2581
2582    def indexconstraintoption_sql(self, expression: exp.IndexConstraintOption) -> str:
2583        key_block_size = self.sql(expression, "key_block_size")
2584        if key_block_size:
2585            return f"KEY_BLOCK_SIZE = {key_block_size}"
2586
2587        using = self.sql(expression, "using")
2588        if using:
2589            return f"USING {using}"
2590
2591        parser = self.sql(expression, "parser")
2592        if parser:
2593            return f"WITH PARSER {parser}"
2594
2595        comment = self.sql(expression, "comment")
2596        if comment:
2597            return f"COMMENT {comment}"
2598
2599        visible = expression.args.get("visible")
2600        if visible is not None:
2601            return "VISIBLE" if visible else "INVISIBLE"
2602
2603        engine_attr = self.sql(expression, "engine_attr")
2604        if engine_attr:
2605            return f"ENGINE_ATTRIBUTE = {engine_attr}"
2606
2607        secondary_engine_attr = self.sql(expression, "secondary_engine_attr")
2608        if secondary_engine_attr:
2609            return f"SECONDARY_ENGINE_ATTRIBUTE = {secondary_engine_attr}"
2610
2611        self.unsupported("Unsupported index constraint option.")
2612        return ""
2613
2614    def indexcolumnconstraint_sql(self, expression: exp.IndexColumnConstraint) -> str:
2615        kind = self.sql(expression, "kind")
2616        kind = f"{kind} INDEX" if kind else "INDEX"
2617        this = self.sql(expression, "this")
2618        this = f" {this}" if this else ""
2619        type_ = self.sql(expression, "type")
2620        type_ = f" USING {type_}" if type_ else ""
2621        schema = self.sql(expression, "schema")
2622        schema = f" {schema}" if schema else ""
2623        options = self.expressions(expression, key="options", sep=" ")
2624        options = f" {options}" if options else ""
2625        return f"{kind}{this}{type_}{schema}{options}"
2626
2627
2628def cached_generator(
2629    cache: t.Optional[t.Dict[int, str]] = None
2630) -> t.Callable[[exp.Expression], str]:
2631    """Returns a cached generator."""
2632    cache = {} if cache is None else cache
2633    generator = Generator(normalize=True, identify="safe")
2634    return lambda e: generator.generate(e, cache)