sqlglot.dialects.snowflake

   1from __future__ import annotations
   2
   3import typing as t
   4
   5from sqlglot import exp, generator, jsonpath, parser, tokens, transforms
   6from sqlglot.dialects.dialect import (
   7    Dialect,
   8    NormalizationStrategy,
   9    build_timetostr_or_tochar,
  10    binary_from_function,
  11    build_default_decimal_type,
  12    build_timestamp_from_parts,
  13    date_delta_sql,
  14    date_trunc_to_time,
  15    datestrtodate_sql,
  16    build_formatted_time,
  17    if_sql,
  18    inline_array_sql,
  19    max_or_greatest,
  20    min_or_least,
  21    rename_func,
  22    timestamptrunc_sql,
  23    timestrtotime_sql,
  24    var_map_sql,
  25    map_date_part,
  26    no_timestamp_sql,
  27    strposition_sql,
  28    timestampdiff_sql,
  29    no_make_interval_sql,
  30    groupconcat_sql,
  31)
  32from sqlglot.generator import unsupported_args
  33from sqlglot.helper import flatten, is_float, is_int, seq_get
  34from sqlglot.tokens import TokenType
  35
  36if t.TYPE_CHECKING:
  37    from sqlglot._typing import E, B
  38
  39
  40# from https://docs.snowflake.com/en/sql-reference/functions/to_timestamp.html
  41def _build_datetime(
  42    name: str, kind: exp.DataType.Type, safe: bool = False
  43) -> t.Callable[[t.List], exp.Func]:
  44    def _builder(args: t.List) -> exp.Func:
  45        value = seq_get(args, 0)
  46        scale_or_fmt = seq_get(args, 1)
  47
  48        int_value = value is not None and is_int(value.name)
  49        int_scale_or_fmt = scale_or_fmt is not None and scale_or_fmt.is_int
  50
  51        if isinstance(value, exp.Literal) or (value and scale_or_fmt):
  52            # Converts calls like `TO_TIME('01:02:03')` into casts
  53            if len(args) == 1 and value.is_string and not int_value:
  54                return (
  55                    exp.TryCast(this=value, to=exp.DataType.build(kind))
  56                    if safe
  57                    else exp.cast(value, kind)
  58                )
  59
  60            # Handles `TO_TIMESTAMP(str, fmt)` and `TO_TIMESTAMP(num, scale)` as special
  61            # cases so we can transpile them, since they're relatively common
  62            if kind == exp.DataType.Type.TIMESTAMP:
  63                if not safe and (int_value or int_scale_or_fmt):
  64                    # TRY_TO_TIMESTAMP('integer') is not parsed into exp.UnixToTime as
  65                    # it's not easily transpilable
  66                    return exp.UnixToTime(this=value, scale=scale_or_fmt)
  67                if not int_scale_or_fmt and not is_float(value.name):
  68                    expr = build_formatted_time(exp.StrToTime, "snowflake")(args)
  69                    expr.set("safe", safe)
  70                    return expr
  71
  72        if kind in (exp.DataType.Type.DATE, exp.DataType.Type.TIME) and not int_value:
  73            klass = exp.TsOrDsToDate if kind == exp.DataType.Type.DATE else exp.TsOrDsToTime
  74            formatted_exp = build_formatted_time(klass, "snowflake")(args)
  75            formatted_exp.set("safe", safe)
  76            return formatted_exp
  77
  78        return exp.Anonymous(this=name, expressions=args)
  79
  80    return _builder
  81
  82
  83def _build_object_construct(args: t.List) -> t.Union[exp.StarMap, exp.Struct]:
  84    expression = parser.build_var_map(args)
  85
  86    if isinstance(expression, exp.StarMap):
  87        return expression
  88
  89    return exp.Struct(
  90        expressions=[
  91            exp.PropertyEQ(this=k, expression=v) for k, v in zip(expression.keys, expression.values)
  92        ]
  93    )
  94
  95
  96def _build_datediff(args: t.List) -> exp.DateDiff:
  97    return exp.DateDiff(
  98        this=seq_get(args, 2), expression=seq_get(args, 1), unit=map_date_part(seq_get(args, 0))
  99    )
 100
 101
 102def _build_date_time_add(expr_type: t.Type[E]) -> t.Callable[[t.List], E]:
 103    def _builder(args: t.List) -> E:
 104        return expr_type(
 105            this=seq_get(args, 2),
 106            expression=seq_get(args, 1),
 107            unit=map_date_part(seq_get(args, 0)),
 108        )
 109
 110    return _builder
 111
 112
 113def _build_bitwise(expr_type: t.Type[B], name: str) -> t.Callable[[t.List], B | exp.Anonymous]:
 114    def _builder(args: t.List) -> B | exp.Anonymous:
 115        if len(args) == 3:
 116            return exp.Anonymous(this=name, expressions=args)
 117
 118        return binary_from_function(expr_type)(args)
 119
 120    return _builder
 121
 122
 123# https://docs.snowflake.com/en/sql-reference/functions/div0
 124def _build_if_from_div0(args: t.List) -> exp.If:
 125    lhs = exp._wrap(seq_get(args, 0), exp.Binary)
 126    rhs = exp._wrap(seq_get(args, 1), exp.Binary)
 127
 128    cond = exp.EQ(this=rhs, expression=exp.Literal.number(0)).and_(
 129        exp.Is(this=lhs, expression=exp.null()).not_()
 130    )
 131    true = exp.Literal.number(0)
 132    false = exp.Div(this=lhs, expression=rhs)
 133    return exp.If(this=cond, true=true, false=false)
 134
 135
 136# https://docs.snowflake.com/en/sql-reference/functions/zeroifnull
 137def _build_if_from_zeroifnull(args: t.List) -> exp.If:
 138    cond = exp.Is(this=seq_get(args, 0), expression=exp.Null())
 139    return exp.If(this=cond, true=exp.Literal.number(0), false=seq_get(args, 0))
 140
 141
 142# https://docs.snowflake.com/en/sql-reference/functions/zeroifnull
 143def _build_if_from_nullifzero(args: t.List) -> exp.If:
 144    cond = exp.EQ(this=seq_get(args, 0), expression=exp.Literal.number(0))
 145    return exp.If(this=cond, true=exp.Null(), false=seq_get(args, 0))
 146
 147
 148def _regexpilike_sql(self: Snowflake.Generator, expression: exp.RegexpILike) -> str:
 149    flag = expression.text("flag")
 150
 151    if "i" not in flag:
 152        flag += "i"
 153
 154    return self.func(
 155        "REGEXP_LIKE", expression.this, expression.expression, exp.Literal.string(flag)
 156    )
 157
 158
 159def _build_regexp_replace(args: t.List) -> exp.RegexpReplace:
 160    regexp_replace = exp.RegexpReplace.from_arg_list(args)
 161
 162    if not regexp_replace.args.get("replacement"):
 163        regexp_replace.set("replacement", exp.Literal.string(""))
 164
 165    return regexp_replace
 166
 167
 168def _show_parser(*args: t.Any, **kwargs: t.Any) -> t.Callable[[Snowflake.Parser], exp.Show]:
 169    def _parse(self: Snowflake.Parser) -> exp.Show:
 170        return self._parse_show_snowflake(*args, **kwargs)
 171
 172    return _parse
 173
 174
 175def _date_trunc_to_time(args: t.List) -> exp.DateTrunc | exp.TimestampTrunc:
 176    trunc = date_trunc_to_time(args)
 177    trunc.set("unit", map_date_part(trunc.args["unit"]))
 178    return trunc
 179
 180
 181def _unqualify_pivot_columns(expression: exp.Expression) -> exp.Expression:
 182    """
 183    Snowflake doesn't allow columns referenced in UNPIVOT to be qualified,
 184    so we need to unqualify them. Same goes for ANY ORDER BY <column>.
 185
 186    Example:
 187        >>> from sqlglot import parse_one
 188        >>> expr = parse_one("SELECT * FROM m_sales UNPIVOT(sales FOR month IN (m_sales.jan, feb, mar, april))")
 189        >>> print(_unqualify_pivot_columns(expr).sql(dialect="snowflake"))
 190        SELECT * FROM m_sales UNPIVOT(sales FOR month IN (jan, feb, mar, april))
 191    """
 192    if isinstance(expression, exp.Pivot):
 193        if expression.unpivot:
 194            expression = transforms.unqualify_columns(expression)
 195        else:
 196            field = expression.args.get("field")
 197            field_expr = seq_get(field.expressions if field else [], 0)
 198
 199            if isinstance(field_expr, exp.PivotAny):
 200                unqualified_field_expr = transforms.unqualify_columns(field_expr)
 201                t.cast(exp.Expression, field).set("expressions", unqualified_field_expr, 0)
 202
 203    return expression
 204
 205
 206def _flatten_structured_types_unless_iceberg(expression: exp.Expression) -> exp.Expression:
 207    assert isinstance(expression, exp.Create)
 208
 209    def _flatten_structured_type(expression: exp.DataType) -> exp.DataType:
 210        if expression.this in exp.DataType.NESTED_TYPES:
 211            expression.set("expressions", None)
 212        return expression
 213
 214    props = expression.args.get("properties")
 215    if isinstance(expression.this, exp.Schema) and not (props and props.find(exp.IcebergProperty)):
 216        for schema_expression in expression.this.expressions:
 217            if isinstance(schema_expression, exp.ColumnDef):
 218                column_type = schema_expression.kind
 219                if isinstance(column_type, exp.DataType):
 220                    column_type.transform(_flatten_structured_type, copy=False)
 221
 222    return expression
 223
 224
 225def _unnest_generate_date_array(unnest: exp.Unnest) -> None:
 226    generate_date_array = unnest.expressions[0]
 227    start = generate_date_array.args.get("start")
 228    end = generate_date_array.args.get("end")
 229    step = generate_date_array.args.get("step")
 230
 231    if not start or not end or not isinstance(step, exp.Interval) or step.name != "1":
 232        return
 233
 234    unit = step.args.get("unit")
 235
 236    unnest_alias = unnest.args.get("alias")
 237    if unnest_alias:
 238        unnest_alias = unnest_alias.copy()
 239        sequence_value_name = seq_get(unnest_alias.columns, 0) or "value"
 240    else:
 241        sequence_value_name = "value"
 242
 243    # We'll add the next sequence value to the starting date and project the result
 244    date_add = _build_date_time_add(exp.DateAdd)(
 245        [unit, exp.cast(sequence_value_name, "int"), exp.cast(start, "date")]
 246    ).as_(sequence_value_name)
 247
 248    # We use DATEDIFF to compute the number of sequence values needed
 249    number_sequence = Snowflake.Parser.FUNCTIONS["ARRAY_GENERATE_RANGE"](
 250        [exp.Literal.number(0), _build_datediff([unit, start, end]) + 1]
 251    )
 252
 253    unnest.set("expressions", [number_sequence])
 254    unnest.replace(exp.select(date_add).from_(unnest.copy()).subquery(unnest_alias))
 255
 256
 257def _transform_generate_date_array(expression: exp.Expression) -> exp.Expression:
 258    if isinstance(expression, exp.Select):
 259        for generate_date_array in expression.find_all(exp.GenerateDateArray):
 260            parent = generate_date_array.parent
 261
 262            # If GENERATE_DATE_ARRAY is used directly as an array (e.g passed into ARRAY_LENGTH), the transformed Snowflake
 263            # query is the following (it'll be unnested properly on the next iteration due to copy):
 264            # SELECT ref(GENERATE_DATE_ARRAY(...)) -> SELECT ref((SELECT ARRAY_AGG(*) FROM UNNEST(GENERATE_DATE_ARRAY(...))))
 265            if not isinstance(parent, exp.Unnest):
 266                unnest = exp.Unnest(expressions=[generate_date_array.copy()])
 267                generate_date_array.replace(
 268                    exp.select(exp.ArrayAgg(this=exp.Star())).from_(unnest).subquery()
 269                )
 270
 271            if (
 272                isinstance(parent, exp.Unnest)
 273                and isinstance(parent.parent, (exp.From, exp.Join))
 274                and len(parent.expressions) == 1
 275            ):
 276                _unnest_generate_date_array(parent)
 277
 278    return expression
 279
 280
 281def _build_regexp_extract(expr_type: t.Type[E]) -> t.Callable[[t.List], E]:
 282    def _builder(args: t.List) -> E:
 283        return expr_type(
 284            this=seq_get(args, 0),
 285            expression=seq_get(args, 1),
 286            position=seq_get(args, 2),
 287            occurrence=seq_get(args, 3),
 288            parameters=seq_get(args, 4),
 289            group=seq_get(args, 5) or exp.Literal.number(0),
 290        )
 291
 292    return _builder
 293
 294
 295def _regexpextract_sql(self, expression: exp.RegexpExtract | exp.RegexpExtractAll) -> str:
 296    # Other dialects don't support all of the following parameters, so we need to
 297    # generate default values as necessary to ensure the transpilation is correct
 298    group = expression.args.get("group")
 299
 300    # To avoid generating all these default values, we set group to None if
 301    # it's 0 (also default value) which doesn't trigger the following chain
 302    if group and group.name == "0":
 303        group = None
 304
 305    parameters = expression.args.get("parameters") or (group and exp.Literal.string("c"))
 306    occurrence = expression.args.get("occurrence") or (parameters and exp.Literal.number(1))
 307    position = expression.args.get("position") or (occurrence and exp.Literal.number(1))
 308
 309    return self.func(
 310        "REGEXP_SUBSTR" if isinstance(expression, exp.RegexpExtract) else "REGEXP_EXTRACT_ALL",
 311        expression.this,
 312        expression.expression,
 313        position,
 314        occurrence,
 315        parameters,
 316        group,
 317    )
 318
 319
 320def _json_extract_value_array_sql(
 321    self: Snowflake.Generator, expression: exp.JSONValueArray | exp.JSONExtractArray
 322) -> str:
 323    json_extract = exp.JSONExtract(this=expression.this, expression=expression.expression)
 324    ident = exp.to_identifier("x")
 325
 326    if isinstance(expression, exp.JSONValueArray):
 327        this: exp.Expression = exp.cast(ident, to=exp.DataType.Type.VARCHAR)
 328    else:
 329        this = exp.ParseJSON(this=f"TO_JSON({ident})")
 330
 331    transform_lambda = exp.Lambda(expressions=[ident], this=this)
 332
 333    return self.func("TRANSFORM", json_extract, transform_lambda)
 334
 335
 336class Snowflake(Dialect):
 337    # https://docs.snowflake.com/en/sql-reference/identifiers-syntax
 338    NORMALIZATION_STRATEGY = NormalizationStrategy.UPPERCASE
 339    NULL_ORDERING = "nulls_are_large"
 340    TIME_FORMAT = "'YYYY-MM-DD HH24:MI:SS'"
 341    SUPPORTS_USER_DEFINED_TYPES = False
 342    SUPPORTS_SEMI_ANTI_JOIN = False
 343    PREFER_CTE_ALIAS_COLUMN = True
 344    TABLESAMPLE_SIZE_IS_PERCENT = True
 345    COPY_PARAMS_ARE_CSV = False
 346    ARRAY_AGG_INCLUDES_NULLS = None
 347
 348    TIME_MAPPING = {
 349        "YYYY": "%Y",
 350        "yyyy": "%Y",
 351        "YY": "%y",
 352        "yy": "%y",
 353        "MMMM": "%B",
 354        "mmmm": "%B",
 355        "MON": "%b",
 356        "mon": "%b",
 357        "MM": "%m",
 358        "mm": "%m",
 359        "DD": "%d",
 360        "dd": "%-d",
 361        "DY": "%a",
 362        "dy": "%w",
 363        "HH24": "%H",
 364        "hh24": "%H",
 365        "HH12": "%I",
 366        "hh12": "%I",
 367        "MI": "%M",
 368        "mi": "%M",
 369        "SS": "%S",
 370        "ss": "%S",
 371        "FF6": "%f",
 372        "ff6": "%f",
 373    }
 374
 375    def quote_identifier(self, expression: E, identify: bool = True) -> E:
 376        # This disables quoting DUAL in SELECT ... FROM DUAL, because Snowflake treats an
 377        # unquoted DUAL keyword in a special way and does not map it to a user-defined table
 378        if (
 379            isinstance(expression, exp.Identifier)
 380            and isinstance(expression.parent, exp.Table)
 381            and expression.name.lower() == "dual"
 382        ):
 383            return expression  # type: ignore
 384
 385        return super().quote_identifier(expression, identify=identify)
 386
 387    class JSONPathTokenizer(jsonpath.JSONPathTokenizer):
 388        SINGLE_TOKENS = jsonpath.JSONPathTokenizer.SINGLE_TOKENS.copy()
 389        SINGLE_TOKENS.pop("$")
 390
 391    class Parser(parser.Parser):
 392        IDENTIFY_PIVOT_STRINGS = True
 393        DEFAULT_SAMPLING_METHOD = "BERNOULLI"
 394        COLON_IS_VARIANT_EXTRACT = True
 395
 396        ID_VAR_TOKENS = {
 397            *parser.Parser.ID_VAR_TOKENS,
 398            TokenType.MATCH_CONDITION,
 399        }
 400
 401        TABLE_ALIAS_TOKENS = parser.Parser.TABLE_ALIAS_TOKENS | {TokenType.WINDOW}
 402        TABLE_ALIAS_TOKENS.discard(TokenType.MATCH_CONDITION)
 403
 404        FUNCTIONS = {
 405            **parser.Parser.FUNCTIONS,
 406            "APPROX_PERCENTILE": exp.ApproxQuantile.from_arg_list,
 407            "ARRAY_CONSTRUCT": lambda args: exp.Array(expressions=args),
 408            "ARRAY_CONTAINS": lambda args: exp.ArrayContains(
 409                this=seq_get(args, 1), expression=seq_get(args, 0)
 410            ),
 411            "ARRAY_GENERATE_RANGE": lambda args: exp.GenerateSeries(
 412                # ARRAY_GENERATE_RANGE has an exlusive end; we normalize it to be inclusive
 413                start=seq_get(args, 0),
 414                end=exp.Sub(this=seq_get(args, 1), expression=exp.Literal.number(1)),
 415                step=seq_get(args, 2),
 416            ),
 417            "BITXOR": _build_bitwise(exp.BitwiseXor, "BITXOR"),
 418            "BIT_XOR": _build_bitwise(exp.BitwiseXor, "BITXOR"),
 419            "BITOR": _build_bitwise(exp.BitwiseOr, "BITOR"),
 420            "BIT_OR": _build_bitwise(exp.BitwiseOr, "BITOR"),
 421            "BITSHIFTLEFT": _build_bitwise(exp.BitwiseLeftShift, "BITSHIFTLEFT"),
 422            "BIT_SHIFTLEFT": _build_bitwise(exp.BitwiseLeftShift, "BIT_SHIFTLEFT"),
 423            "BITSHIFTRIGHT": _build_bitwise(exp.BitwiseRightShift, "BITSHIFTRIGHT"),
 424            "BIT_SHIFTRIGHT": _build_bitwise(exp.BitwiseRightShift, "BIT_SHIFTRIGHT"),
 425            "BOOLXOR": _build_bitwise(exp.Xor, "BOOLXOR"),
 426            "DATE": _build_datetime("DATE", exp.DataType.Type.DATE),
 427            "DATE_TRUNC": _date_trunc_to_time,
 428            "DATEADD": _build_date_time_add(exp.DateAdd),
 429            "DATEDIFF": _build_datediff,
 430            "DIV0": _build_if_from_div0,
 431            "EDITDISTANCE": lambda args: exp.Levenshtein(
 432                this=seq_get(args, 0), expression=seq_get(args, 1), max_dist=seq_get(args, 2)
 433            ),
 434            "FLATTEN": exp.Explode.from_arg_list,
 435            "GET_PATH": lambda args, dialect: exp.JSONExtract(
 436                this=seq_get(args, 0), expression=dialect.to_json_path(seq_get(args, 1))
 437            ),
 438            "HEX_DECODE_BINARY": exp.Unhex.from_arg_list,
 439            "IFF": exp.If.from_arg_list,
 440            "LAST_DAY": lambda args: exp.LastDay(
 441                this=seq_get(args, 0), unit=map_date_part(seq_get(args, 1))
 442            ),
 443            "LEN": lambda args: exp.Length(this=seq_get(args, 0), binary=True),
 444            "LENGTH": lambda args: exp.Length(this=seq_get(args, 0), binary=True),
 445            "NULLIFZERO": _build_if_from_nullifzero,
 446            "OBJECT_CONSTRUCT": _build_object_construct,
 447            "REGEXP_EXTRACT_ALL": _build_regexp_extract(exp.RegexpExtractAll),
 448            "REGEXP_REPLACE": _build_regexp_replace,
 449            "REGEXP_SUBSTR": _build_regexp_extract(exp.RegexpExtract),
 450            "REGEXP_SUBSTR_ALL": _build_regexp_extract(exp.RegexpExtractAll),
 451            "RLIKE": exp.RegexpLike.from_arg_list,
 452            "SQUARE": lambda args: exp.Pow(this=seq_get(args, 0), expression=exp.Literal.number(2)),
 453            "TABLE": lambda args: exp.TableFromRows(this=seq_get(args, 0)),
 454            "TIMEADD": _build_date_time_add(exp.TimeAdd),
 455            "TIMEDIFF": _build_datediff,
 456            "TIMESTAMPADD": _build_date_time_add(exp.DateAdd),
 457            "TIMESTAMPDIFF": _build_datediff,
 458            "TIMESTAMPFROMPARTS": build_timestamp_from_parts,
 459            "TIMESTAMP_FROM_PARTS": build_timestamp_from_parts,
 460            "TIMESTAMPNTZFROMPARTS": build_timestamp_from_parts,
 461            "TIMESTAMP_NTZ_FROM_PARTS": build_timestamp_from_parts,
 462            "TRY_PARSE_JSON": lambda args: exp.ParseJSON(this=seq_get(args, 0), safe=True),
 463            "TRY_TO_DATE": _build_datetime("TRY_TO_DATE", exp.DataType.Type.DATE, safe=True),
 464            "TRY_TO_TIME": _build_datetime("TRY_TO_TIME", exp.DataType.Type.TIME, safe=True),
 465            "TRY_TO_TIMESTAMP": _build_datetime(
 466                "TRY_TO_TIMESTAMP", exp.DataType.Type.TIMESTAMP, safe=True
 467            ),
 468            "TO_CHAR": build_timetostr_or_tochar,
 469            "TO_DATE": _build_datetime("TO_DATE", exp.DataType.Type.DATE),
 470            "TO_NUMBER": lambda args: exp.ToNumber(
 471                this=seq_get(args, 0),
 472                format=seq_get(args, 1),
 473                precision=seq_get(args, 2),
 474                scale=seq_get(args, 3),
 475            ),
 476            "TO_TIME": _build_datetime("TO_TIME", exp.DataType.Type.TIME),
 477            "TO_TIMESTAMP": _build_datetime("TO_TIMESTAMP", exp.DataType.Type.TIMESTAMP),
 478            "TO_TIMESTAMP_LTZ": _build_datetime("TO_TIMESTAMP_LTZ", exp.DataType.Type.TIMESTAMPLTZ),
 479            "TO_TIMESTAMP_NTZ": _build_datetime("TO_TIMESTAMP_NTZ", exp.DataType.Type.TIMESTAMP),
 480            "TO_TIMESTAMP_TZ": _build_datetime("TO_TIMESTAMP_TZ", exp.DataType.Type.TIMESTAMPTZ),
 481            "TO_VARCHAR": exp.ToChar.from_arg_list,
 482            "ZEROIFNULL": _build_if_from_zeroifnull,
 483        }
 484
 485        FUNCTION_PARSERS = {
 486            **parser.Parser.FUNCTION_PARSERS,
 487            "DATE_PART": lambda self: self._parse_date_part(),
 488            "OBJECT_CONSTRUCT_KEEP_NULL": lambda self: self._parse_json_object(),
 489            "LISTAGG": lambda self: self._parse_string_agg(),
 490        }
 491        FUNCTION_PARSERS.pop("TRIM")
 492
 493        TIMESTAMPS = parser.Parser.TIMESTAMPS - {TokenType.TIME}
 494
 495        RANGE_PARSERS = {
 496            **parser.Parser.RANGE_PARSERS,
 497            TokenType.LIKE_ANY: parser.binary_range_parser(exp.LikeAny),
 498            TokenType.ILIKE_ANY: parser.binary_range_parser(exp.ILikeAny),
 499        }
 500
 501        ALTER_PARSERS = {
 502            **parser.Parser.ALTER_PARSERS,
 503            "UNSET": lambda self: self.expression(
 504                exp.Set,
 505                tag=self._match_text_seq("TAG"),
 506                expressions=self._parse_csv(self._parse_id_var),
 507                unset=True,
 508            ),
 509        }
 510
 511        STATEMENT_PARSERS = {
 512            **parser.Parser.STATEMENT_PARSERS,
 513            TokenType.PUT: lambda self: self._parse_put(),
 514            TokenType.SHOW: lambda self: self._parse_show(),
 515        }
 516
 517        PROPERTY_PARSERS = {
 518            **parser.Parser.PROPERTY_PARSERS,
 519            "LOCATION": lambda self: self._parse_location_property(),
 520            "TAG": lambda self: self._parse_tag(),
 521            "USING": lambda self: self._match_text_seq("TEMPLATE")
 522            and self.expression(exp.UsingTemplateProperty, this=self._parse_statement()),
 523        }
 524
 525        TYPE_CONVERTERS = {
 526            # https://docs.snowflake.com/en/sql-reference/data-types-numeric#number
 527            exp.DataType.Type.DECIMAL: build_default_decimal_type(precision=38, scale=0),
 528        }
 529
 530        SHOW_PARSERS = {
 531            "DATABASES": _show_parser("DATABASES"),
 532            "TERSE DATABASES": _show_parser("DATABASES"),
 533            "SCHEMAS": _show_parser("SCHEMAS"),
 534            "TERSE SCHEMAS": _show_parser("SCHEMAS"),
 535            "OBJECTS": _show_parser("OBJECTS"),
 536            "TERSE OBJECTS": _show_parser("OBJECTS"),
 537            "TABLES": _show_parser("TABLES"),
 538            "TERSE TABLES": _show_parser("TABLES"),
 539            "VIEWS": _show_parser("VIEWS"),
 540            "TERSE VIEWS": _show_parser("VIEWS"),
 541            "PRIMARY KEYS": _show_parser("PRIMARY KEYS"),
 542            "TERSE PRIMARY KEYS": _show_parser("PRIMARY KEYS"),
 543            "IMPORTED KEYS": _show_parser("IMPORTED KEYS"),
 544            "TERSE IMPORTED KEYS": _show_parser("IMPORTED KEYS"),
 545            "UNIQUE KEYS": _show_parser("UNIQUE KEYS"),
 546            "TERSE UNIQUE KEYS": _show_parser("UNIQUE KEYS"),
 547            "SEQUENCES": _show_parser("SEQUENCES"),
 548            "TERSE SEQUENCES": _show_parser("SEQUENCES"),
 549            "COLUMNS": _show_parser("COLUMNS"),
 550            "USERS": _show_parser("USERS"),
 551            "TERSE USERS": _show_parser("USERS"),
 552            "FUNCTIONS": _show_parser("FUNCTIONS"),
 553            "PROCEDURES": _show_parser("PROCEDURES"),
 554            "WAREHOUSES": _show_parser("WAREHOUSES"),
 555        }
 556
 557        CONSTRAINT_PARSERS = {
 558            **parser.Parser.CONSTRAINT_PARSERS,
 559            "WITH": lambda self: self._parse_with_constraint(),
 560            "MASKING": lambda self: self._parse_with_constraint(),
 561            "PROJECTION": lambda self: self._parse_with_constraint(),
 562            "TAG": lambda self: self._parse_with_constraint(),
 563        }
 564
 565        STAGED_FILE_SINGLE_TOKENS = {
 566            TokenType.DOT,
 567            TokenType.MOD,
 568            TokenType.SLASH,
 569        }
 570
 571        FLATTEN_COLUMNS = ["SEQ", "KEY", "PATH", "INDEX", "VALUE", "THIS"]
 572
 573        SCHEMA_KINDS = {"OBJECTS", "TABLES", "VIEWS", "SEQUENCES", "UNIQUE KEYS", "IMPORTED KEYS"}
 574
 575        NON_TABLE_CREATABLES = {"STORAGE INTEGRATION", "TAG", "WAREHOUSE", "STREAMLIT"}
 576
 577        LAMBDAS = {
 578            **parser.Parser.LAMBDAS,
 579            TokenType.ARROW: lambda self, expressions: self.expression(
 580                exp.Lambda,
 581                this=self._replace_lambda(
 582                    self._parse_assignment(),
 583                    expressions,
 584                ),
 585                expressions=[e.this if isinstance(e, exp.Cast) else e for e in expressions],
 586            ),
 587        }
 588
 589        def _parse_use(self) -> exp.Use:
 590            if self._match_text_seq("SECONDARY", "ROLES"):
 591                this = self._match_texts(("ALL", "NONE")) and exp.var(self._prev.text.upper())
 592                roles = None if this else self._parse_csv(lambda: self._parse_table(schema=False))
 593                return self.expression(
 594                    exp.Use, kind="SECONDARY ROLES", this=this, expressions=roles
 595                )
 596
 597            return super()._parse_use()
 598
 599        def _negate_range(
 600            self, this: t.Optional[exp.Expression] = None
 601        ) -> t.Optional[exp.Expression]:
 602            if not this:
 603                return this
 604
 605            query = this.args.get("query")
 606            if isinstance(this, exp.In) and isinstance(query, exp.Query):
 607                # Snowflake treats `value NOT IN (subquery)` as `VALUE <> ALL (subquery)`, so
 608                # we do this conversion here to avoid parsing it into `NOT value IN (subquery)`
 609                # which can produce different results (most likely a SnowFlake bug).
 610                #
 611                # https://docs.snowflake.com/en/sql-reference/functions/in
 612                # Context: https://github.com/tobymao/sqlglot/issues/3890
 613                return self.expression(
 614                    exp.NEQ, this=this.this, expression=exp.All(this=query.unnest())
 615                )
 616
 617            return self.expression(exp.Not, this=this)
 618
 619        def _parse_tag(self) -> exp.Tags:
 620            return self.expression(
 621                exp.Tags,
 622                expressions=self._parse_wrapped_csv(self._parse_property),
 623            )
 624
 625        def _parse_with_constraint(self) -> t.Optional[exp.Expression]:
 626            if self._prev.token_type != TokenType.WITH:
 627                self._retreat(self._index - 1)
 628
 629            if self._match_text_seq("MASKING", "POLICY"):
 630                policy = self._parse_column()
 631                return self.expression(
 632                    exp.MaskingPolicyColumnConstraint,
 633                    this=policy.to_dot() if isinstance(policy, exp.Column) else policy,
 634                    expressions=self._match(TokenType.USING)
 635                    and self._parse_wrapped_csv(self._parse_id_var),
 636                )
 637            if self._match_text_seq("PROJECTION", "POLICY"):
 638                policy = self._parse_column()
 639                return self.expression(
 640                    exp.ProjectionPolicyColumnConstraint,
 641                    this=policy.to_dot() if isinstance(policy, exp.Column) else policy,
 642                )
 643            if self._match(TokenType.TAG):
 644                return self._parse_tag()
 645
 646            return None
 647
 648        def _parse_with_property(self) -> t.Optional[exp.Expression] | t.List[exp.Expression]:
 649            if self._match(TokenType.TAG):
 650                return self._parse_tag()
 651
 652            return super()._parse_with_property()
 653
 654        def _parse_create(self) -> exp.Create | exp.Command:
 655            expression = super()._parse_create()
 656            if isinstance(expression, exp.Create) and expression.kind in self.NON_TABLE_CREATABLES:
 657                # Replace the Table node with the enclosed Identifier
 658                expression.this.replace(expression.this.this)
 659
 660            return expression
 661
 662        # https://docs.snowflake.com/en/sql-reference/functions/date_part.html
 663        # https://docs.snowflake.com/en/sql-reference/functions-date-time.html#label-supported-date-time-parts
 664        def _parse_date_part(self: Snowflake.Parser) -> t.Optional[exp.Expression]:
 665            this = self._parse_var() or self._parse_type()
 666
 667            if not this:
 668                return None
 669
 670            self._match(TokenType.COMMA)
 671            expression = self._parse_bitwise()
 672            this = map_date_part(this)
 673            name = this.name.upper()
 674
 675            if name.startswith("EPOCH"):
 676                if name == "EPOCH_MILLISECOND":
 677                    scale = 10**3
 678                elif name == "EPOCH_MICROSECOND":
 679                    scale = 10**6
 680                elif name == "EPOCH_NANOSECOND":
 681                    scale = 10**9
 682                else:
 683                    scale = None
 684
 685                ts = self.expression(exp.Cast, this=expression, to=exp.DataType.build("TIMESTAMP"))
 686                to_unix: exp.Expression = self.expression(exp.TimeToUnix, this=ts)
 687
 688                if scale:
 689                    to_unix = exp.Mul(this=to_unix, expression=exp.Literal.number(scale))
 690
 691                return to_unix
 692
 693            return self.expression(exp.Extract, this=this, expression=expression)
 694
 695        def _parse_bracket_key_value(self, is_map: bool = False) -> t.Optional[exp.Expression]:
 696            if is_map:
 697                # Keys are strings in Snowflake's objects, see also:
 698                # - https://docs.snowflake.com/en/sql-reference/data-types-semistructured
 699                # - https://docs.snowflake.com/en/sql-reference/functions/object_construct
 700                return self._parse_slice(self._parse_string())
 701
 702            return self._parse_slice(self._parse_alias(self._parse_assignment(), explicit=True))
 703
 704        def _parse_lateral(self) -> t.Optional[exp.Lateral]:
 705            lateral = super()._parse_lateral()
 706            if not lateral:
 707                return lateral
 708
 709            if isinstance(lateral.this, exp.Explode):
 710                table_alias = lateral.args.get("alias")
 711                columns = [exp.to_identifier(col) for col in self.FLATTEN_COLUMNS]
 712                if table_alias and not table_alias.args.get("columns"):
 713                    table_alias.set("columns", columns)
 714                elif not table_alias:
 715                    exp.alias_(lateral, "_flattened", table=columns, copy=False)
 716
 717            return lateral
 718
 719        def _parse_table_parts(
 720            self, schema: bool = False, is_db_reference: bool = False, wildcard: bool = False
 721        ) -> exp.Table:
 722            # https://docs.snowflake.com/en/user-guide/querying-stage
 723            if self._match(TokenType.STRING, advance=False):
 724                table = self._parse_string()
 725            elif self._match_text_seq("@", advance=False):
 726                table = self._parse_location_path()
 727            else:
 728                table = None
 729
 730            if table:
 731                file_format = None
 732                pattern = None
 733
 734                wrapped = self._match(TokenType.L_PAREN)
 735                while self._curr and wrapped and not self._match(TokenType.R_PAREN):
 736                    if self._match_text_seq("FILE_FORMAT", "=>"):
 737                        file_format = self._parse_string() or super()._parse_table_parts(
 738                            is_db_reference=is_db_reference
 739                        )
 740                    elif self._match_text_seq("PATTERN", "=>"):
 741                        pattern = self._parse_string()
 742                    else:
 743                        break
 744
 745                    self._match(TokenType.COMMA)
 746
 747                table = self.expression(exp.Table, this=table, format=file_format, pattern=pattern)
 748            else:
 749                table = super()._parse_table_parts(schema=schema, is_db_reference=is_db_reference)
 750
 751            return table
 752
 753        def _parse_table(
 754            self,
 755            schema: bool = False,
 756            joins: bool = False,
 757            alias_tokens: t.Optional[t.Collection[TokenType]] = None,
 758            parse_bracket: bool = False,
 759            is_db_reference: bool = False,
 760            parse_partition: bool = False,
 761        ) -> t.Optional[exp.Expression]:
 762            table = super()._parse_table(
 763                schema=schema,
 764                joins=joins,
 765                alias_tokens=alias_tokens,
 766                parse_bracket=parse_bracket,
 767                is_db_reference=is_db_reference,
 768                parse_partition=parse_partition,
 769            )
 770            if isinstance(table, exp.Table) and isinstance(table.this, exp.TableFromRows):
 771                table_from_rows = table.this
 772                for arg in exp.TableFromRows.arg_types:
 773                    if arg != "this":
 774                        table_from_rows.set(arg, table.args.get(arg))
 775
 776                table = table_from_rows
 777
 778            return table
 779
 780        def _parse_id_var(
 781            self,
 782            any_token: bool = True,
 783            tokens: t.Optional[t.Collection[TokenType]] = None,
 784        ) -> t.Optional[exp.Expression]:
 785            if self._match_text_seq("IDENTIFIER", "("):
 786                identifier = (
 787                    super()._parse_id_var(any_token=any_token, tokens=tokens)
 788                    or self._parse_string()
 789                )
 790                self._match_r_paren()
 791                return self.expression(exp.Anonymous, this="IDENTIFIER", expressions=[identifier])
 792
 793            return super()._parse_id_var(any_token=any_token, tokens=tokens)
 794
 795        def _parse_show_snowflake(self, this: str) -> exp.Show:
 796            scope = None
 797            scope_kind = None
 798
 799            # will identity SHOW TERSE SCHEMAS but not SHOW TERSE PRIMARY KEYS
 800            # which is syntactically valid but has no effect on the output
 801            terse = self._tokens[self._index - 2].text.upper() == "TERSE"
 802
 803            history = self._match_text_seq("HISTORY")
 804
 805            like = self._parse_string() if self._match(TokenType.LIKE) else None
 806
 807            if self._match(TokenType.IN):
 808                if self._match_text_seq("ACCOUNT"):
 809                    scope_kind = "ACCOUNT"
 810                elif self._match_text_seq("CLASS"):
 811                    scope_kind = "CLASS"
 812                    scope = self._parse_table_parts()
 813                elif self._match_text_seq("APPLICATION"):
 814                    scope_kind = "APPLICATION"
 815                    if self._match_text_seq("PACKAGE"):
 816                        scope_kind += " PACKAGE"
 817                    scope = self._parse_table_parts()
 818                elif self._match_set(self.DB_CREATABLES):
 819                    scope_kind = self._prev.text.upper()
 820                    if self._curr:
 821                        scope = self._parse_table_parts()
 822                elif self._curr:
 823                    scope_kind = "SCHEMA" if this in self.SCHEMA_KINDS else "TABLE"
 824                    scope = self._parse_table_parts()
 825
 826            return self.expression(
 827                exp.Show,
 828                **{
 829                    "terse": terse,
 830                    "this": this,
 831                    "history": history,
 832                    "like": like,
 833                    "scope": scope,
 834                    "scope_kind": scope_kind,
 835                    "starts_with": self._match_text_seq("STARTS", "WITH") and self._parse_string(),
 836                    "limit": self._parse_limit(),
 837                    "from": self._parse_string() if self._match(TokenType.FROM) else None,
 838                    "privileges": self._match_text_seq("WITH", "PRIVILEGES")
 839                    and self._parse_csv(lambda: self._parse_var(any_token=True, upper=True)),
 840                },
 841            )
 842
 843        def _parse_put(self) -> exp.Put | exp.Command:
 844            if self._curr.token_type != TokenType.STRING:
 845                return self._parse_as_command(self._prev)
 846
 847            return self.expression(
 848                exp.Put,
 849                this=self._parse_string(),
 850                target=self._parse_location_path(),
 851                properties=self._parse_properties(),
 852            )
 853
 854        def _parse_location_property(self) -> exp.LocationProperty:
 855            self._match(TokenType.EQ)
 856            return self.expression(exp.LocationProperty, this=self._parse_location_path())
 857
 858        def _parse_file_location(self) -> t.Optional[exp.Expression]:
 859            # Parse either a subquery or a staged file
 860            return (
 861                self._parse_select(table=True, parse_subquery_alias=False)
 862                if self._match(TokenType.L_PAREN, advance=False)
 863                else self._parse_table_parts()
 864            )
 865
 866        def _parse_location_path(self) -> exp.Var:
 867            start = self._curr
 868            self._advance_any(ignore_reserved=True)
 869
 870            # We avoid consuming a comma token because external tables like @foo and @bar
 871            # can be joined in a query with a comma separator, as well as closing paren
 872            # in case of subqueries
 873            while self._is_connected() and not self._match_set(
 874                (TokenType.COMMA, TokenType.L_PAREN, TokenType.R_PAREN), advance=False
 875            ):
 876                self._advance_any(ignore_reserved=True)
 877
 878            return exp.var(self._find_sql(start, self._prev))
 879
 880        def _parse_lambda_arg(self) -> t.Optional[exp.Expression]:
 881            this = super()._parse_lambda_arg()
 882
 883            if not this:
 884                return this
 885
 886            typ = self._parse_types()
 887
 888            if typ:
 889                return self.expression(exp.Cast, this=this, to=typ)
 890
 891            return this
 892
 893        def _parse_foreign_key(self) -> exp.ForeignKey:
 894            # inlineFK, the REFERENCES columns are implied
 895            if self._match(TokenType.REFERENCES, advance=False):
 896                return self.expression(exp.ForeignKey)
 897
 898            # outoflineFK, explicitly names the columns
 899            return super()._parse_foreign_key()
 900
 901    class Tokenizer(tokens.Tokenizer):
 902        STRING_ESCAPES = ["\\", "'"]
 903        HEX_STRINGS = [("x'", "'"), ("X'", "'")]
 904        RAW_STRINGS = ["$$"]
 905        COMMENTS = ["--", "//", ("/*", "*/")]
 906        NESTED_COMMENTS = False
 907
 908        KEYWORDS = {
 909            **tokens.Tokenizer.KEYWORDS,
 910            "FILE://": TokenType.URI_START,
 911            "BYTEINT": TokenType.INT,
 912            "CHAR VARYING": TokenType.VARCHAR,
 913            "CHARACTER VARYING": TokenType.VARCHAR,
 914            "EXCLUDE": TokenType.EXCEPT,
 915            "ILIKE ANY": TokenType.ILIKE_ANY,
 916            "LIKE ANY": TokenType.LIKE_ANY,
 917            "MATCH_CONDITION": TokenType.MATCH_CONDITION,
 918            "MATCH_RECOGNIZE": TokenType.MATCH_RECOGNIZE,
 919            "MINUS": TokenType.EXCEPT,
 920            "NCHAR VARYING": TokenType.VARCHAR,
 921            "PUT": TokenType.PUT,
 922            "REMOVE": TokenType.COMMAND,
 923            "RM": TokenType.COMMAND,
 924            "SAMPLE": TokenType.TABLE_SAMPLE,
 925            "SQL_DOUBLE": TokenType.DOUBLE,
 926            "SQL_VARCHAR": TokenType.VARCHAR,
 927            "STORAGE INTEGRATION": TokenType.STORAGE_INTEGRATION,
 928            "TAG": TokenType.TAG,
 929            "TIMESTAMP_TZ": TokenType.TIMESTAMPTZ,
 930            "TOP": TokenType.TOP,
 931            "WAREHOUSE": TokenType.WAREHOUSE,
 932            "STREAMLIT": TokenType.STREAMLIT,
 933        }
 934        KEYWORDS.pop("/*+")
 935
 936        SINGLE_TOKENS = {
 937            **tokens.Tokenizer.SINGLE_TOKENS,
 938            "$": TokenType.PARAMETER,
 939        }
 940
 941        VAR_SINGLE_TOKENS = {"$"}
 942
 943        COMMANDS = tokens.Tokenizer.COMMANDS - {TokenType.SHOW}
 944
 945    class Generator(generator.Generator):
 946        PARAMETER_TOKEN = "$"
 947        MATCHED_BY_SOURCE = False
 948        SINGLE_STRING_INTERVAL = True
 949        JOIN_HINTS = False
 950        TABLE_HINTS = False
 951        QUERY_HINTS = False
 952        AGGREGATE_FILTER_SUPPORTED = False
 953        SUPPORTS_TABLE_COPY = False
 954        COLLATE_IS_FUNC = True
 955        LIMIT_ONLY_LITERALS = True
 956        JSON_KEY_VALUE_PAIR_SEP = ","
 957        INSERT_OVERWRITE = " OVERWRITE INTO"
 958        STRUCT_DELIMITER = ("(", ")")
 959        COPY_PARAMS_ARE_WRAPPED = False
 960        COPY_PARAMS_EQ_REQUIRED = True
 961        STAR_EXCEPT = "EXCLUDE"
 962        SUPPORTS_EXPLODING_PROJECTIONS = False
 963        ARRAY_CONCAT_IS_VAR_LEN = False
 964        SUPPORTS_CONVERT_TIMEZONE = True
 965        EXCEPT_INTERSECT_SUPPORT_ALL_CLAUSE = False
 966        SUPPORTS_MEDIAN = True
 967        ARRAY_SIZE_NAME = "ARRAY_SIZE"
 968
 969        TRANSFORMS = {
 970            **generator.Generator.TRANSFORMS,
 971            exp.ApproxDistinct: rename_func("APPROX_COUNT_DISTINCT"),
 972            exp.ArgMax: rename_func("MAX_BY"),
 973            exp.ArgMin: rename_func("MIN_BY"),
 974            exp.Array: inline_array_sql,
 975            exp.ArrayConcat: lambda self, e: self.arrayconcat_sql(e, name="ARRAY_CAT"),
 976            exp.ArrayContains: lambda self, e: self.func("ARRAY_CONTAINS", e.expression, e.this),
 977            exp.AtTimeZone: lambda self, e: self.func(
 978                "CONVERT_TIMEZONE", e.args.get("zone"), e.this
 979            ),
 980            exp.BitwiseOr: rename_func("BITOR"),
 981            exp.BitwiseXor: rename_func("BITXOR"),
 982            exp.BitwiseLeftShift: rename_func("BITSHIFTLEFT"),
 983            exp.BitwiseRightShift: rename_func("BITSHIFTRIGHT"),
 984            exp.Create: transforms.preprocess([_flatten_structured_types_unless_iceberg]),
 985            exp.DateAdd: date_delta_sql("DATEADD"),
 986            exp.DateDiff: date_delta_sql("DATEDIFF"),
 987            exp.DatetimeAdd: date_delta_sql("TIMESTAMPADD"),
 988            exp.DatetimeDiff: timestampdiff_sql,
 989            exp.DateStrToDate: datestrtodate_sql,
 990            exp.DayOfMonth: rename_func("DAYOFMONTH"),
 991            exp.DayOfWeek: rename_func("DAYOFWEEK"),
 992            exp.DayOfYear: rename_func("DAYOFYEAR"),
 993            exp.Explode: rename_func("FLATTEN"),
 994            exp.Extract: rename_func("DATE_PART"),
 995            exp.FromTimeZone: lambda self, e: self.func(
 996                "CONVERT_TIMEZONE", e.args.get("zone"), "'UTC'", e.this
 997            ),
 998            exp.GenerateSeries: lambda self, e: self.func(
 999                "ARRAY_GENERATE_RANGE", e.args["start"], e.args["end"] + 1, e.args.get("step")
1000            ),
1001            exp.GroupConcat: lambda self, e: groupconcat_sql(self, e, sep=""),
1002            exp.If: if_sql(name="IFF", false_value="NULL"),
1003            exp.JSONExtractArray: _json_extract_value_array_sql,
1004            exp.JSONExtractScalar: lambda self, e: self.func(
1005                "JSON_EXTRACT_PATH_TEXT", e.this, e.expression
1006            ),
1007            exp.JSONObject: lambda self, e: self.func("OBJECT_CONSTRUCT_KEEP_NULL", *e.expressions),
1008            exp.JSONPathRoot: lambda *_: "",
1009            exp.JSONValueArray: _json_extract_value_array_sql,
1010            exp.LogicalAnd: rename_func("BOOLAND_AGG"),
1011            exp.LogicalOr: rename_func("BOOLOR_AGG"),
1012            exp.Map: lambda self, e: var_map_sql(self, e, "OBJECT_CONSTRUCT"),
1013            exp.MakeInterval: no_make_interval_sql,
1014            exp.Max: max_or_greatest,
1015            exp.Min: min_or_least,
1016            exp.ParseJSON: lambda self, e: self.func(
1017                "TRY_PARSE_JSON" if e.args.get("safe") else "PARSE_JSON", e.this
1018            ),
1019            exp.PartitionedByProperty: lambda self, e: f"PARTITION BY {self.sql(e, 'this')}",
1020            exp.PercentileCont: transforms.preprocess(
1021                [transforms.add_within_group_for_percentiles]
1022            ),
1023            exp.PercentileDisc: transforms.preprocess(
1024                [transforms.add_within_group_for_percentiles]
1025            ),
1026            exp.Pivot: transforms.preprocess([_unqualify_pivot_columns]),
1027            exp.RegexpExtract: _regexpextract_sql,
1028            exp.RegexpExtractAll: _regexpextract_sql,
1029            exp.RegexpILike: _regexpilike_sql,
1030            exp.Rand: rename_func("RANDOM"),
1031            exp.Select: transforms.preprocess(
1032                [
1033                    transforms.eliminate_distinct_on,
1034                    transforms.explode_projection_to_unnest(),
1035                    transforms.eliminate_semi_and_anti_joins,
1036                    _transform_generate_date_array,
1037                ]
1038            ),
1039            exp.SHA: rename_func("SHA1"),
1040            exp.StarMap: rename_func("OBJECT_CONSTRUCT"),
1041            exp.StartsWith: rename_func("STARTSWITH"),
1042            exp.StrPosition: lambda self, e: strposition_sql(
1043                self, e, func_name="CHARINDEX", supports_position=True
1044            ),
1045            exp.StrToDate: lambda self, e: self.func("DATE", e.this, self.format_time(e)),
1046            exp.Stuff: rename_func("INSERT"),
1047            exp.TimeAdd: date_delta_sql("TIMEADD"),
1048            exp.Timestamp: no_timestamp_sql,
1049            exp.TimestampAdd: date_delta_sql("TIMESTAMPADD"),
1050            exp.TimestampDiff: lambda self, e: self.func(
1051                "TIMESTAMPDIFF", e.unit, e.expression, e.this
1052            ),
1053            exp.TimestampTrunc: timestamptrunc_sql(),
1054            exp.TimeStrToTime: timestrtotime_sql,
1055            exp.TimeToUnix: lambda self, e: f"EXTRACT(epoch_second FROM {self.sql(e, 'this')})",
1056            exp.ToArray: rename_func("TO_ARRAY"),
1057            exp.ToChar: lambda self, e: self.function_fallback_sql(e),
1058            exp.ToDouble: rename_func("TO_DOUBLE"),
1059            exp.TsOrDsAdd: date_delta_sql("DATEADD", cast=True),
1060            exp.TsOrDsDiff: date_delta_sql("DATEDIFF"),
1061            exp.TsOrDsToDate: lambda self, e: self.func(
1062                "TRY_TO_DATE" if e.args.get("safe") else "TO_DATE", e.this, self.format_time(e)
1063            ),
1064            exp.TsOrDsToTime: lambda self, e: self.func(
1065                "TRY_TO_TIME" if e.args.get("safe") else "TO_TIME", e.this, self.format_time(e)
1066            ),
1067            exp.Unhex: rename_func("HEX_DECODE_BINARY"),
1068            exp.UnixToTime: rename_func("TO_TIMESTAMP"),
1069            exp.Uuid: rename_func("UUID_STRING"),
1070            exp.VarMap: lambda self, e: var_map_sql(self, e, "OBJECT_CONSTRUCT"),
1071            exp.WeekOfYear: rename_func("WEEKOFYEAR"),
1072            exp.Xor: rename_func("BOOLXOR"),
1073            exp.Levenshtein: unsupported_args("ins_cost", "del_cost", "sub_cost")(
1074                rename_func("EDITDISTANCE")
1075            ),
1076        }
1077
1078        SUPPORTED_JSON_PATH_PARTS = {
1079            exp.JSONPathKey,
1080            exp.JSONPathRoot,
1081            exp.JSONPathSubscript,
1082        }
1083
1084        TYPE_MAPPING = {
1085            **generator.Generator.TYPE_MAPPING,
1086            exp.DataType.Type.NESTED: "OBJECT",
1087            exp.DataType.Type.STRUCT: "OBJECT",
1088        }
1089
1090        TOKEN_MAPPING = {
1091            TokenType.AUTO_INCREMENT: "AUTOINCREMENT",
1092        }
1093
1094        PROPERTIES_LOCATION = {
1095            **generator.Generator.PROPERTIES_LOCATION,
1096            exp.SetProperty: exp.Properties.Location.UNSUPPORTED,
1097            exp.VolatileProperty: exp.Properties.Location.UNSUPPORTED,
1098        }
1099
1100        UNSUPPORTED_VALUES_EXPRESSIONS = {
1101            exp.Map,
1102            exp.StarMap,
1103            exp.Struct,
1104            exp.VarMap,
1105        }
1106
1107        def with_properties(self, properties: exp.Properties) -> str:
1108            return self.properties(properties, wrapped=False, prefix=self.sep(""), sep=" ")
1109
1110        def values_sql(self, expression: exp.Values, values_as_table: bool = True) -> str:
1111            if expression.find(*self.UNSUPPORTED_VALUES_EXPRESSIONS):
1112                values_as_table = False
1113
1114            return super().values_sql(expression, values_as_table=values_as_table)
1115
1116        def datatype_sql(self, expression: exp.DataType) -> str:
1117            expressions = expression.expressions
1118            if (
1119                expressions
1120                and expression.is_type(*exp.DataType.STRUCT_TYPES)
1121                and any(isinstance(field_type, exp.DataType) for field_type in expressions)
1122            ):
1123                # The correct syntax is OBJECT [ (<key> <value_type [NOT NULL] [, ...]) ]
1124                return "OBJECT"
1125
1126            return super().datatype_sql(expression)
1127
1128        def tonumber_sql(self, expression: exp.ToNumber) -> str:
1129            return self.func(
1130                "TO_NUMBER",
1131                expression.this,
1132                expression.args.get("format"),
1133                expression.args.get("precision"),
1134                expression.args.get("scale"),
1135            )
1136
1137        def timestampfromparts_sql(self, expression: exp.TimestampFromParts) -> str:
1138            milli = expression.args.get("milli")
1139            if milli is not None:
1140                milli_to_nano = milli.pop() * exp.Literal.number(1000000)
1141                expression.set("nano", milli_to_nano)
1142
1143            return rename_func("TIMESTAMP_FROM_PARTS")(self, expression)
1144
1145        def cast_sql(self, expression: exp.Cast, safe_prefix: t.Optional[str] = None) -> str:
1146            if expression.is_type(exp.DataType.Type.GEOGRAPHY):
1147                return self.func("TO_GEOGRAPHY", expression.this)
1148            if expression.is_type(exp.DataType.Type.GEOMETRY):
1149                return self.func("TO_GEOMETRY", expression.this)
1150
1151            return super().cast_sql(expression, safe_prefix=safe_prefix)
1152
1153        def trycast_sql(self, expression: exp.TryCast) -> str:
1154            value = expression.this
1155
1156            if value.type is None:
1157                from sqlglot.optimizer.annotate_types import annotate_types
1158
1159                value = annotate_types(value)
1160
1161            if value.is_type(*exp.DataType.TEXT_TYPES, exp.DataType.Type.UNKNOWN):
1162                return super().trycast_sql(expression)
1163
1164            # TRY_CAST only works for string values in Snowflake
1165            return self.cast_sql(expression)
1166
1167        def log_sql(self, expression: exp.Log) -> str:
1168            if not expression.expression:
1169                return self.func("LN", expression.this)
1170
1171            return super().log_sql(expression)
1172
1173        def unnest_sql(self, expression: exp.Unnest) -> str:
1174            unnest_alias = expression.args.get("alias")
1175            offset = expression.args.get("offset")
1176
1177            columns = [
1178                exp.to_identifier("seq"),
1179                exp.to_identifier("key"),
1180                exp.to_identifier("path"),
1181                offset.pop() if isinstance(offset, exp.Expression) else exp.to_identifier("index"),
1182                seq_get(unnest_alias.columns if unnest_alias else [], 0)
1183                or exp.to_identifier("value"),
1184                exp.to_identifier("this"),
1185            ]
1186
1187            if unnest_alias:
1188                unnest_alias.set("columns", columns)
1189            else:
1190                unnest_alias = exp.TableAlias(this="_u", columns=columns)
1191
1192            table_input = self.sql(expression.expressions[0])
1193            if not table_input.startswith("INPUT =>"):
1194                table_input = f"INPUT => {table_input}"
1195
1196            explode = f"TABLE(FLATTEN({table_input}))"
1197            alias = self.sql(unnest_alias)
1198            alias = f" AS {alias}" if alias else ""
1199            return f"{explode}{alias}"
1200
1201        def show_sql(self, expression: exp.Show) -> str:
1202            terse = "TERSE " if expression.args.get("terse") else ""
1203            history = " HISTORY" if expression.args.get("history") else ""
1204            like = self.sql(expression, "like")
1205            like = f" LIKE {like}" if like else ""
1206
1207            scope = self.sql(expression, "scope")
1208            scope = f" {scope}" if scope else ""
1209
1210            scope_kind = self.sql(expression, "scope_kind")
1211            if scope_kind:
1212                scope_kind = f" IN {scope_kind}"
1213
1214            starts_with = self.sql(expression, "starts_with")
1215            if starts_with:
1216                starts_with = f" STARTS WITH {starts_with}"
1217
1218            limit = self.sql(expression, "limit")
1219
1220            from_ = self.sql(expression, "from")
1221            if from_:
1222                from_ = f" FROM {from_}"
1223
1224            privileges = self.expressions(expression, key="privileges", flat=True)
1225            privileges = f" WITH PRIVILEGES {privileges}" if privileges else ""
1226
1227            return f"SHOW {terse}{expression.name}{history}{like}{scope_kind}{scope}{starts_with}{limit}{from_}{privileges}"
1228
1229        def describe_sql(self, expression: exp.Describe) -> str:
1230            # Default to table if kind is unknown
1231            kind_value = expression.args.get("kind") or "TABLE"
1232            kind = f" {kind_value}" if kind_value else ""
1233            this = f" {self.sql(expression, 'this')}"
1234            expressions = self.expressions(expression, flat=True)
1235            expressions = f" {expressions}" if expressions else ""
1236            return f"DESCRIBE{kind}{this}{expressions}"
1237
1238        def generatedasidentitycolumnconstraint_sql(
1239            self, expression: exp.GeneratedAsIdentityColumnConstraint
1240        ) -> str:
1241            start = expression.args.get("start")
1242            start = f" START {start}" if start else ""
1243            increment = expression.args.get("increment")
1244            increment = f" INCREMENT {increment}" if increment else ""
1245            return f"AUTOINCREMENT{start}{increment}"
1246
1247        def cluster_sql(self, expression: exp.Cluster) -> str:
1248            return f"CLUSTER BY ({self.expressions(expression, flat=True)})"
1249
1250        def struct_sql(self, expression: exp.Struct) -> str:
1251            keys = []
1252            values = []
1253
1254            for i, e in enumerate(expression.expressions):
1255                if isinstance(e, exp.PropertyEQ):
1256                    keys.append(
1257                        exp.Literal.string(e.name) if isinstance(e.this, exp.Identifier) else e.this
1258                    )
1259                    values.append(e.expression)
1260                else:
1261                    keys.append(exp.Literal.string(f"_{i}"))
1262                    values.append(e)
1263
1264            return self.func("OBJECT_CONSTRUCT", *flatten(zip(keys, values)))
1265
1266        @unsupported_args("weight", "accuracy")
1267        def approxquantile_sql(self, expression: exp.ApproxQuantile) -> str:
1268            return self.func("APPROX_PERCENTILE", expression.this, expression.args.get("quantile"))
1269
1270        def alterset_sql(self, expression: exp.AlterSet) -> str:
1271            exprs = self.expressions(expression, flat=True)
1272            exprs = f" {exprs}" if exprs else ""
1273            file_format = self.expressions(expression, key="file_format", flat=True, sep=" ")
1274            file_format = f" STAGE_FILE_FORMAT = ({file_format})" if file_format else ""
1275            copy_options = self.expressions(expression, key="copy_options", flat=True, sep=" ")
1276            copy_options = f" STAGE_COPY_OPTIONS = ({copy_options})" if copy_options else ""
1277            tag = self.expressions(expression, key="tag", flat=True)
1278            tag = f" TAG {tag}" if tag else ""
1279
1280            return f"SET{exprs}{file_format}{copy_options}{tag}"
1281
1282        def strtotime_sql(self, expression: exp.StrToTime):
1283            safe_prefix = "TRY_" if expression.args.get("safe") else ""
1284            return self.func(
1285                f"{safe_prefix}TO_TIMESTAMP", expression.this, self.format_time(expression)
1286            )
1287
1288        def timestampsub_sql(self, expression: exp.TimestampSub):
1289            return self.sql(
1290                exp.TimestampAdd(
1291                    this=expression.this,
1292                    expression=expression.expression * -1,
1293                    unit=expression.unit,
1294                )
1295            )
1296
1297        def jsonextract_sql(self, expression: exp.JSONExtract):
1298            this = expression.this
1299
1300            # JSON strings are valid coming from other dialects such as BQ
1301            return self.func(
1302                "GET_PATH",
1303                exp.ParseJSON(this=this) if this.is_string else this,
1304                expression.expression,
1305            )
1306
1307        def timetostr_sql(self, expression: exp.TimeToStr) -> str:
1308            this = expression.this
1309            if not isinstance(this, exp.TsOrDsToTimestamp):
1310                this = exp.cast(this, exp.DataType.Type.TIMESTAMP)
1311
1312            return self.func("TO_CHAR", this, self.format_time(expression))
1313
1314        def datesub_sql(self, expression: exp.DateSub) -> str:
1315            value = expression.expression
1316            if value:
1317                value.replace(value * (-1))
1318            else:
1319                self.unsupported("DateSub cannot be transpiled if the subtracted count is unknown")
1320
1321            return date_delta_sql("DATEADD")(self, expression)
1322
1323        def select_sql(self, expression: exp.Select) -> str:
1324            limit = expression.args.get("limit")
1325            offset = expression.args.get("offset")
1326            if offset and not limit:
1327                expression.limit(exp.Null(), copy=False)
1328            return super().select_sql(expression)