sqlglot.generators.snowflake

   1from __future__ import annotations
   2
   3import typing as t
   4from collections import defaultdict
   5
   6from sqlglot import exp, generator, transforms
   7from sqlglot.dialects.dialect import (
   8    array_append_sql,
   9    array_concat_sql,
  10    date_delta_sql,
  11    datestrtodate_sql,
  12    groupconcat_sql,
  13    if_sql,
  14    inline_array_sql,
  15    map_date_part,
  16    max_or_greatest,
  17    min_or_least,
  18    no_filter_sql,
  19    no_make_interval_sql,
  20    no_timestamp_sql,
  21    nth_value_from_sql,
  22    rename_func,
  23    strposition_sql,
  24    timestampdiff_sql,
  25    timestamptrunc_sql,
  26    timestrtotime_sql,
  27    unit_to_str,
  28    var_map_sql,
  29)
  30from sqlglot.generator import unsupported_args
  31from sqlglot.helper import find_new_name, flatten, seq_get
  32from sqlglot.optimizer.scope import build_scope, find_all_in_scope
  33from sqlglot.parsers.snowflake import (
  34    RANKING_WINDOW_FUNCTIONS_WITH_FRAME,
  35    TIMESTAMP_TYPES,
  36    SnowflakeParser,
  37    build_object_construct,
  38)
  39from sqlglot.tokens import TokenType
  40
  41if t.TYPE_CHECKING:
  42    from sqlglot._typing import E
  43
  44
  45def _build_datediff(args: list) -> exp.DateDiff:
  46    return exp.DateDiff(
  47        this=seq_get(args, 2),
  48        expression=seq_get(args, 1),
  49        unit=map_date_part(seq_get(args, 0)),
  50        date_part_boundary=True,
  51    )
  52
  53
  54def _build_date_time_add(expr_type: type[E]) -> t.Callable[[list], E]:
  55    def _builder(args: list) -> E:
  56        return expr_type(
  57            this=seq_get(args, 2),
  58            expression=seq_get(args, 1),
  59            unit=map_date_part(seq_get(args, 0)),
  60        )
  61
  62    return _builder
  63
  64
  65def _regexpilike_sql(self: SnowflakeGenerator, expression: exp.RegexpILike) -> str:
  66    flag = expression.text("flag")
  67
  68    if "i" not in flag:
  69        flag += "i"
  70
  71    return self.func(
  72        "REGEXP_LIKE", expression.this, expression.expression, exp.Literal.string(flag)
  73    )
  74
  75
  76def _unqualify_pivot_columns(expression: exp.Expr) -> exp.Expr:
  77    """
  78    Snowflake doesn't allow columns referenced in UNPIVOT to be qualified,
  79    so we need to unqualify them. Same goes for ANY ORDER BY <column>.
  80
  81    Example:
  82        >>> from sqlglot import parse_one
  83        >>> expr = parse_one("SELECT * FROM m_sales UNPIVOT(sales FOR month IN (m_sales.jan, feb, mar, april))")
  84        >>> print(_unqualify_pivot_columns(expr).sql(dialect="snowflake"))
  85        SELECT * FROM m_sales UNPIVOT(sales FOR month IN (jan, feb, mar, april))
  86    """
  87    if isinstance(expression, exp.Pivot):
  88        if expression.unpivot:
  89            expression = transforms.unqualify_columns(expression)
  90        else:
  91            for field in expression.fields:
  92                field_expr = seq_get(field.expressions if field else [], 0)
  93
  94                if isinstance(field_expr, exp.PivotAny):
  95                    unqualified_field_expr = transforms.unqualify_columns(field_expr)
  96                    t.cast(exp.Expr, field).set("expressions", unqualified_field_expr, 0)
  97
  98    return expression
  99
 100
 101def _unnest_generate_date_array(unnest: exp.Unnest) -> None:
 102    generate_date_array = unnest.expressions[0]
 103    start = generate_date_array.args.get("start")
 104    end = generate_date_array.args.get("end")
 105    step = generate_date_array.args.get("step")
 106
 107    if not start or not end or not isinstance(step, exp.Interval) or step.name != "1":
 108        return
 109
 110    unit = step.args.get("unit")
 111
 112    unnest_alias = unnest.args.get("alias")
 113    if unnest_alias:
 114        unnest_alias = unnest_alias.copy()
 115        sequence_value_name = seq_get(unnest_alias.columns, 0) or "value"
 116    else:
 117        sequence_value_name = "value"
 118
 119    # We'll add the next sequence value to the starting date and project the result
 120    date_add = _build_date_time_add(exp.DateAdd)(
 121        [unit, exp.cast(sequence_value_name, "int"), exp.cast(start, "date")]
 122    )
 123
 124    # We use DATEDIFF to compute the number of sequence values needed
 125    number_sequence = SnowflakeParser.FUNCTIONS["ARRAY_GENERATE_RANGE"](
 126        [exp.Literal.number(0), _build_datediff([unit, start, end]) + 1]
 127    )
 128
 129    unnest.set("expressions", [number_sequence])
 130
 131    unnest_parent = unnest.parent
 132    if isinstance(unnest_parent, exp.Join):
 133        select = unnest_parent.parent
 134        if isinstance(select, exp.Select):
 135            replace_column_name = (
 136                sequence_value_name
 137                if isinstance(sequence_value_name, str)
 138                else sequence_value_name.name
 139            )
 140
 141            scope = build_scope(select)
 142            if scope:
 143                for column in scope.columns:
 144                    if column.name.lower() == replace_column_name.lower():
 145                        column.replace(
 146                            date_add.as_(replace_column_name)
 147                            if isinstance(column.parent, exp.Select)
 148                            else date_add
 149                        )
 150
 151            lateral = exp.Lateral(this=unnest_parent.this.pop())
 152            unnest_parent.replace(exp.Join(this=lateral))
 153    else:
 154        unnest.replace(
 155            exp.select(date_add.as_(sequence_value_name))
 156            .from_(unnest.copy())
 157            .subquery(unnest_alias)
 158        )
 159
 160
 161def _transform_generate_date_array(expression: exp.Expr) -> exp.Expr:
 162    if isinstance(expression, exp.Select):
 163        for generate_date_array in expression.find_all(exp.GenerateDateArray):
 164            parent = generate_date_array.parent
 165
 166            # If GENERATE_DATE_ARRAY is used directly as an array (e.g passed into ARRAY_LENGTH), the transformed Snowflake
 167            # query is the following (it'll be unnested properly on the next iteration due to copy):
 168            # SELECT ref(GENERATE_DATE_ARRAY(...)) -> SELECT ref((SELECT ARRAY_AGG(*) FROM UNNEST(GENERATE_DATE_ARRAY(...))))
 169            if not isinstance(parent, exp.Unnest):
 170                unnest = exp.Unnest(expressions=[generate_date_array.copy()])
 171                generate_date_array.replace(
 172                    exp.select(exp.ArrayAgg(this=exp.Star())).from_(unnest).subquery()
 173                )
 174
 175            if (
 176                isinstance(parent, exp.Unnest)
 177                and isinstance(parent.parent, (exp.From, exp.Join))
 178                and len(parent.expressions) == 1
 179            ):
 180                _unnest_generate_date_array(parent)
 181
 182    return expression
 183
 184
 185@unsupported_args(("expression", "Snowflake's ARRAY_SORT does not support a comparator."))
 186def _array_sort_sql(self: SnowflakeGenerator, expression: exp.ArraySort) -> str:
 187    # NULLs default to last when ascending and first when descending
 188    asc = expression.args.get("asc")
 189    nulls_first = expression.args.get("nulls_first")
 190    if asc is None and nulls_first == exp.false():
 191        nulls_first = None
 192    elif asc is None and nulls_first is not None:
 193        asc = exp.true()
 194    elif asc == exp.false() and nulls_first == exp.true():
 195        nulls_first = None
 196    return self.func("ARRAY_SORT", expression.this, asc, nulls_first)
 197
 198
 199def _regexpextract_sql(
 200    self: SnowflakeGenerator, expression: exp.RegexpExtract | exp.RegexpExtractAll
 201) -> str:
 202    # Other dialects don't support all of the following parameters, so we need to
 203    # generate default values as necessary to ensure the transpilation is correct
 204    group = expression.args.get("group")
 205
 206    # To avoid generating all these default values, we set group to None if
 207    # it's 0 (also default value) which doesn't trigger the following chain
 208    if group and group.name == "0":
 209        group = None
 210
 211    parameters = expression.args.get("parameters") or (group and exp.Literal.string("c"))
 212    occurrence = expression.args.get("occurrence") or (parameters and exp.Literal.number(1))
 213    position = expression.args.get("position") or (occurrence and exp.Literal.number(1))
 214
 215    return self.func(
 216        "REGEXP_SUBSTR" if isinstance(expression, exp.RegexpExtract) else "REGEXP_SUBSTR_ALL",
 217        expression.this,
 218        expression.expression,
 219        position,
 220        occurrence,
 221        parameters,
 222        group,
 223    )
 224
 225
 226def _json_extract_value_array_sql(
 227    self: SnowflakeGenerator, expression: exp.JSONValueArray | exp.JSONExtractArray
 228) -> str:
 229    json_extract = exp.JSONExtract(this=expression.this, expression=expression.expression)
 230    ident = exp.to_identifier("x")
 231
 232    if isinstance(expression, exp.JSONValueArray):
 233        this: exp.Expr = exp.cast(ident, to=exp.DType.VARCHAR)
 234    else:
 235        this = exp.ParseJSON(this=f"TO_JSON({ident})")
 236
 237    transform_lambda = exp.Lambda(expressions=[ident], this=this)
 238
 239    return self.func("TRANSFORM", json_extract, transform_lambda)
 240
 241
 242def _qualify_unnested_columns(expression: exp.Expr) -> exp.Expr:
 243    if isinstance(expression, exp.Select):
 244        scope = build_scope(expression)
 245        if not scope:
 246            return expression
 247
 248        unnests = list(scope.find_all(exp.Unnest))
 249
 250        if not unnests:
 251            return expression
 252
 253        taken_source_names = set(scope.sources)
 254        column_source: dict[str, exp.Identifier] = {}
 255        unnest_to_identifier: dict[exp.Unnest, exp.Identifier] = {}
 256
 257        unnest_identifier: exp.Identifier | None = None
 258        orig_expression = expression.copy()
 259
 260        for unnest in unnests:
 261            if not isinstance(unnest.parent, (exp.From, exp.Join)):
 262                continue
 263
 264            # Try to infer column names produced by an unnest operator. This is only possible
 265            # when we can peek into the (statically known) contents of the unnested value.
 266            unnest_columns: set[str] = set()
 267            for unnest_expr in unnest.expressions:
 268                if not isinstance(unnest_expr, exp.Array):
 269                    continue
 270
 271                for array_expr in unnest_expr.expressions:
 272                    if not (
 273                        isinstance(array_expr, exp.Struct)
 274                        and array_expr.expressions
 275                        and all(
 276                            isinstance(struct_expr, exp.PropertyEQ)
 277                            for struct_expr in array_expr.expressions
 278                        )
 279                    ):
 280                        continue
 281
 282                    unnest_columns.update(
 283                        struct_expr.this.name.lower() for struct_expr in array_expr.expressions
 284                    )
 285                    break
 286
 287                if unnest_columns:
 288                    break
 289
 290            unnest_alias = unnest.args.get("alias")
 291            if not unnest_alias:
 292                alias_name = find_new_name(taken_source_names, "value")
 293                taken_source_names.add(alias_name)
 294
 295                # Produce a `TableAlias` AST similar to what is produced for BigQuery. This
 296                # will be corrected later, when we generate SQL for the `Unnest` AST node.
 297                aliased_unnest = exp.alias_(unnest, None, table=[alias_name])
 298                scope.replace(unnest, aliased_unnest)
 299
 300                unnest_identifier = aliased_unnest.args["alias"].columns[0]
 301            else:
 302                alias_columns = getattr(unnest_alias, "columns", [])
 303                unnest_identifier = unnest_alias.this or seq_get(alias_columns, 0)
 304
 305            if not isinstance(unnest_identifier, exp.Identifier):
 306                return orig_expression
 307
 308            unnest_to_identifier[unnest] = unnest_identifier
 309            column_source.update({c.lower(): unnest_identifier for c in unnest_columns})
 310
 311        for column in scope.columns:
 312            if column.table:
 313                continue
 314
 315            table = column_source.get(column.name.lower())
 316            if (
 317                unnest_identifier
 318                and not table
 319                and len(scope.sources) == 1
 320                and column.name.lower() != unnest_identifier.name.lower()
 321            ):
 322                unnest_ancestor = column.find_ancestor(exp.Unnest, exp.Select)
 323                if isinstance(unnest_ancestor, exp.Unnest):
 324                    ancestor_identifier = unnest_to_identifier.get(unnest_ancestor)
 325                    if (
 326                        ancestor_identifier
 327                        and ancestor_identifier.name.lower() == unnest_identifier.name.lower()
 328                    ):
 329                        continue
 330
 331                table = unnest_identifier
 332
 333            column.set("table", table and table.copy())
 334
 335    return expression
 336
 337
 338def _eliminate_dot_variant_lookup(expression: exp.Expr) -> exp.Expr:
 339    if isinstance(expression, exp.Select):
 340        # This transformation is used to facilitate transpilation of BigQuery `UNNEST` operations
 341        # to Snowflake. It should not affect roundtrip because `Unnest` nodes cannot be produced
 342        # by Snowflake's parser.
 343        #
 344        # Additionally, at the time of writing this, BigQuery is the only dialect that produces a
 345        # `TableAlias` node that only fills `columns` and not `this`, due to `UNNEST_COLUMN_ONLY`.
 346        unnest_aliases = set()
 347        for unnest in find_all_in_scope(expression, exp.Unnest):
 348            unnest_alias = unnest.args.get("alias")
 349            if (
 350                isinstance(unnest_alias, exp.TableAlias)
 351                and not unnest_alias.this
 352                and len(unnest_alias.columns) == 1
 353            ):
 354                unnest_aliases.add(unnest_alias.columns[0].name)
 355
 356        if unnest_aliases:
 357            for c in find_all_in_scope(expression, exp.Column):
 358                if c.table in unnest_aliases:
 359                    bracket_lhs = c.args["table"]
 360                    bracket_rhs = exp.Literal.string(c.name)
 361                    bracket = exp.Bracket(this=bracket_lhs, expressions=[bracket_rhs])
 362
 363                    if c.parent is expression:
 364                        # Retain column projection names by using aliases
 365                        c.replace(exp.alias_(bracket, c.this.copy()))
 366                    else:
 367                        c.replace(bracket)
 368
 369    return expression
 370
 371
 372class SnowflakeGenerator(generator.Generator):
 373    BYTE_STRING_FUNCTION = "HEX_DECODE_BINARY"
 374    SELECT_KINDS: tuple[str, ...] = ()
 375    PARAMETER_TOKEN = "$"
 376    MATCHED_BY_SOURCE = False
 377    MERGE_ALL_BY_NAME = True
 378    SINGLE_STRING_INTERVAL = True
 379    CAST_TO_INT_ROUNDS = True
 380    JOIN_HINTS = False
 381    TABLE_HINTS = False
 382    QUERY_HINTS = False
 383    SUPPORTS_TABLE_COPY = False
 384    COLLATE_IS_FUNC = True
 385    LIMIT_ONLY_LITERALS = True
 386    JSON_KEY_VALUE_PAIR_SEP = ","
 387    INSERT_OVERWRITE = " OVERWRITE INTO"
 388    STRUCT_DELIMITER = ("(", ")")
 389    COPY_PARAMS_ARE_WRAPPED = False
 390    COPY_PARAMS_EQ_REQUIRED = True
 391    STAR_EXCEPT = "EXCLUDE"
 392    SUPPORTS_EXPLODING_PROJECTIONS = False
 393    ARRAY_CONCAT_IS_VAR_LEN = False
 394    SUPPORTS_CONVERT_TIMEZONE = True
 395    EXCEPT_INTERSECT_SUPPORT_ALL_CLAUSE = False
 396    SUPPORTS_MEDIAN = True
 397    ARRAY_SIZE_NAME = "ARRAY_SIZE"
 398    SUPPORTS_DECODE_CASE = True
 399    ALTER_TABLE_INCLUDE_COLUMN_KEYWORD = False
 400    ALTER_TABLE_ADD_COLUMNS_WRAPPED = False
 401
 402    AFTER_HAVING_MODIFIER_TRANSFORMS = generator.AFTER_HAVING_MODIFIER_TRANSFORMS
 403
 404    IS_BOOL_ALLOWED = False
 405    DIRECTED_JOINS = True
 406    SUPPORTS_UESCAPE = False
 407    TRY_SUPPORTED = False
 408
 409    TRANSFORMS = {
 410        **generator.Generator.TRANSFORMS,
 411        exp.ApproxDistinct: rename_func("APPROX_COUNT_DISTINCT"),
 412        exp.ArgMax: rename_func("MAX_BY"),
 413        exp.ArgMin: rename_func("MIN_BY"),
 414        exp.Array: transforms.preprocess([transforms.inherit_struct_field_names]),
 415        exp.ArrayConcat: array_concat_sql("ARRAY_CAT"),
 416        exp.ArrayAppend: array_append_sql("ARRAY_APPEND"),
 417        exp.ArrayPrepend: array_append_sql("ARRAY_PREPEND"),
 418        exp.ArrayContains: lambda self, e: self.func(
 419            "ARRAY_CONTAINS",
 420            e.expression
 421            if e.args.get("ensure_variant") is False
 422            else exp.cast(e.expression, exp.DType.VARIANT, copy=False),
 423            e.this,
 424        ),
 425        exp.ArrayPosition: lambda self, e: self.func(
 426            "ARRAY_POSITION",
 427            e.expression,
 428            e.this,
 429        ),
 430        exp.ArrayIntersect: rename_func("ARRAY_INTERSECTION"),
 431        exp.ArrayOverlaps: rename_func("ARRAYS_OVERLAP"),
 432        exp.ArraySort: _array_sort_sql,
 433        exp.AtTimeZone: lambda self, e: self.func("CONVERT_TIMEZONE", e.args.get("zone"), e.this),
 434        exp.BitwiseOr: rename_func("BITOR"),
 435        exp.BitwiseXor: rename_func("BITXOR"),
 436        exp.BitwiseAnd: rename_func("BITAND"),
 437        exp.BitwiseAndAgg: rename_func("BITANDAGG"),
 438        exp.BitwiseOrAgg: rename_func("BITORAGG"),
 439        exp.BitwiseXorAgg: rename_func("BITXORAGG"),
 440        exp.BitwiseNot: rename_func("BITNOT"),
 441        exp.BitwiseLeftShift: rename_func("BITSHIFTLEFT"),
 442        exp.BitwiseRightShift: rename_func("BITSHIFTRIGHT"),
 443        exp.CurrentTimestamp: lambda self, e: (
 444            self.func("SYSDATE") if e.args.get("sysdate") else self.function_fallback_sql(e)
 445        ),
 446        exp.CurrentSchemas: lambda self, e: self.func("CURRENT_SCHEMAS"),
 447        exp.Localtime: lambda self, e: (
 448            self.func("CURRENT_TIME", e.this) if e.this else "CURRENT_TIME"
 449        ),
 450        exp.Localtimestamp: lambda self, e: (
 451            self.func("CURRENT_TIMESTAMP", e.this) if e.this else "CURRENT_TIMESTAMP"
 452        ),
 453        exp.DateAdd: date_delta_sql("DATEADD"),
 454        exp.DateDiff: date_delta_sql("DATEDIFF"),
 455        exp.DatetimeAdd: date_delta_sql("TIMESTAMPADD"),
 456        exp.DatetimeDiff: timestampdiff_sql,
 457        exp.DateStrToDate: datestrtodate_sql,
 458        exp.Decrypt: lambda self, e: self.func(
 459            f"{'TRY_' if e.args.get('safe') else ''}DECRYPT",
 460            e.this,
 461            e.args.get("passphrase"),
 462            e.args.get("aad"),
 463            e.args.get("encryption_method"),
 464        ),
 465        exp.DecryptRaw: lambda self, e: self.func(
 466            f"{'TRY_' if e.args.get('safe') else ''}DECRYPT_RAW",
 467            e.this,
 468            e.args.get("key"),
 469            e.args.get("iv"),
 470            e.args.get("aad"),
 471            e.args.get("encryption_method"),
 472            e.args.get("aead"),
 473        ),
 474        exp.DayOfMonth: rename_func("DAYOFMONTH"),
 475        exp.DayOfWeek: rename_func("DAYOFWEEK"),
 476        exp.DayOfWeekIso: rename_func("DAYOFWEEKISO"),
 477        exp.DayOfYear: rename_func("DAYOFYEAR"),
 478        exp.DotProduct: rename_func("VECTOR_INNER_PRODUCT"),
 479        exp.Explode: rename_func("FLATTEN"),
 480        exp.Extract: lambda self, e: self.func(
 481            "DATE_PART", map_date_part(e.this, self.dialect), e.expression
 482        ),
 483        exp.Filter: no_filter_sql,
 484        exp.CosineDistance: rename_func("VECTOR_COSINE_SIMILARITY"),
 485        exp.EuclideanDistance: rename_func("VECTOR_L2_DISTANCE"),
 486        exp.HandlerProperty: lambda self, e: f"HANDLER = {self.sql(e, 'this')}",
 487        exp.FileFormatProperty: lambda self, e: (
 488            f"FILE_FORMAT=({self.expressions(e, 'expressions', sep=' ')})"
 489        ),
 490        exp.FromTimeZone: lambda self, e: self.func(
 491            "CONVERT_TIMEZONE", e.args.get("zone"), "'UTC'", e.this
 492        ),
 493        exp.GenerateSeries: lambda self, e: self.func(
 494            "ARRAY_GENERATE_RANGE",
 495            e.args["start"],
 496            e.args["end"] if e.args.get("is_end_exclusive") else e.args["end"] + 1,
 497            e.args.get("step"),
 498        ),
 499        exp.GetExtract: rename_func("GET"),
 500        exp.GroupConcat: lambda self, e: groupconcat_sql(self, e, sep=""),
 501        exp.If: if_sql(name="IFF", false_value="NULL"),
 502        exp.InteractiveProperty: lambda *_: "INTERACTIVE",
 503        exp.JSONArray: lambda self, e: self.func(
 504            "TO_VARIANT", self.func("ARRAY_CONSTRUCT", *e.expressions)
 505        ),
 506        exp.JSONExtractArray: _json_extract_value_array_sql,
 507        exp.JSONExtractScalar: lambda self, e: self.func(
 508            "JSON_EXTRACT_PATH_TEXT", e.this, e.expression
 509        ),
 510        exp.JSONKeys: rename_func("OBJECT_KEYS"),
 511        exp.JSONObject: lambda self, e: self.func("OBJECT_CONSTRUCT_KEEP_NULL", *e.expressions),
 512        exp.JSONPathRoot: lambda *_: "",
 513        exp.JSONValueArray: _json_extract_value_array_sql,
 514        exp.Levenshtein: unsupported_args("ins_cost", "del_cost", "sub_cost")(
 515            rename_func("EDITDISTANCE")
 516        ),
 517        exp.LocationProperty: lambda self, e: f"LOCATION={self.sql(e, 'this')}",
 518        exp.LogicalAnd: rename_func("BOOLAND_AGG"),
 519        exp.LogicalOr: rename_func("BOOLOR_AGG"),
 520        exp.Map: lambda self, e: var_map_sql(self, e, "OBJECT_CONSTRUCT"),
 521        exp.ManhattanDistance: rename_func("VECTOR_L1_DISTANCE"),
 522        exp.MakeInterval: no_make_interval_sql,
 523        exp.Max: max_or_greatest,
 524        exp.Min: min_or_least,
 525        exp.NthValue: nth_value_from_sql,
 526        exp.ParseJSON: lambda self, e: self.func(
 527            f"{'TRY_' if e.args.get('safe') else ''}PARSE_JSON", e.this
 528        ),
 529        exp.ToBinary: lambda self, e: self.func(
 530            f"{'TRY_' if e.args.get('safe') else ''}TO_BINARY", e.this, e.args.get("format")
 531        ),
 532        exp.ToBoolean: lambda self, e: self.func(
 533            f"{'TRY_' if e.args.get('safe') else ''}TO_BOOLEAN", e.this
 534        ),
 535        exp.ToDouble: lambda self, e: self.func(
 536            f"{'TRY_' if e.args.get('safe') else ''}TO_DOUBLE", e.this, e.args.get("format")
 537        ),
 538        exp.ToFile: lambda self, e: self.func(
 539            f"{'TRY_' if e.args.get('safe') else ''}TO_FILE", e.this, e.args.get("path")
 540        ),
 541        exp.JSONFormat: rename_func("TO_JSON"),
 542        exp.PartitionedByProperty: lambda self, e: f"PARTITION BY {self.sql(e, 'this')}",
 543        exp.PercentileCont: transforms.preprocess([transforms.add_within_group_for_percentiles]),
 544        exp.PercentileDisc: transforms.preprocess([transforms.add_within_group_for_percentiles]),
 545        exp.Pivot: transforms.preprocess([_unqualify_pivot_columns]),
 546        exp.RegexpExtract: _regexpextract_sql,
 547        exp.RegexpExtractAll: _regexpextract_sql,
 548        exp.RegexpILike: _regexpilike_sql,
 549        exp.RowAccessProperty: lambda self, e: self.rowaccessproperty_sql(e),
 550        exp.Select: transforms.preprocess(
 551            [
 552                transforms.eliminate_window_clause,
 553                transforms.eliminate_distinct_on,
 554                transforms.explode_projection_to_unnest(),
 555                transforms.eliminate_semi_and_anti_joins,
 556                _transform_generate_date_array,
 557                _qualify_unnested_columns,
 558                _eliminate_dot_variant_lookup,
 559            ]
 560        ),
 561        exp.SHA: rename_func("SHA1"),
 562        exp.SHA1Digest: rename_func("SHA1_BINARY"),
 563        exp.MD5Digest: rename_func("MD5_BINARY"),
 564        exp.MD5NumberLower64: rename_func("MD5_NUMBER_LOWER64"),
 565        exp.MD5NumberUpper64: rename_func("MD5_NUMBER_UPPER64"),
 566        exp.Hex: rename_func("HEX_ENCODE"),
 567        exp.LowerHex: rename_func("TO_CHAR"),
 568        exp.Skewness: rename_func("SKEW"),
 569        exp.StarMap: rename_func("OBJECT_CONSTRUCT"),
 570        exp.StartsWith: rename_func("STARTSWITH"),
 571        exp.EndsWith: rename_func("ENDSWITH"),
 572        exp.Rand: lambda self, e: self.func("RANDOM", e.this),
 573        exp.StrPosition: lambda self, e: strposition_sql(
 574            self, e, func_name="CHARINDEX", supports_position=True
 575        ),
 576        exp.StrToDate: lambda self, e: self.func("DATE", e.this, self.format_time(e)),
 577        exp.StringToArray: rename_func("STRTOK_TO_ARRAY"),
 578        exp.StrtokToArray: rename_func("STRTOK_TO_ARRAY"),
 579        exp.Stuff: rename_func("INSERT"),
 580        exp.StPoint: rename_func("ST_MAKEPOINT"),
 581        exp.TemporaryProperty: lambda _, e: (
 582            "SCOPED TEMPORARY" if e.args.get("scoped") else "TEMPORARY"
 583        ),
 584        exp.TimeAdd: date_delta_sql("TIMEADD"),
 585        exp.TimeSlice: lambda self, e: self.func(
 586            "TIME_SLICE",
 587            e.this,
 588            e.expression,
 589            unit_to_str(e),
 590            e.args.get("kind"),
 591        ),
 592        exp.Timestamp: no_timestamp_sql,
 593        exp.TimestampAdd: date_delta_sql("TIMESTAMPADD"),
 594        exp.TimestampDiff: lambda self, e: self.func("TIMESTAMPDIFF", e.unit, e.expression, e.this),
 595        exp.TimestampTrunc: timestamptrunc_sql(),
 596        exp.TimeStrToTime: timestrtotime_sql,
 597        exp.TimeToUnix: lambda self, e: f"EXTRACT(epoch_second FROM {self.sql(e, 'this')})",
 598        exp.ToArray: rename_func("TO_ARRAY"),
 599        exp.ToChar: lambda self, e: self.function_fallback_sql(e),
 600        exp.TsOrDsAdd: date_delta_sql("DATEADD", cast=True),
 601        exp.TsOrDsDiff: date_delta_sql("DATEDIFF"),
 602        exp.TsOrDsToDate: lambda self, e: self.func(
 603            f"{'TRY_' if e.args.get('safe') else ''}TO_DATE", e.this, self.format_time(e)
 604        ),
 605        exp.TsOrDsToTime: lambda self, e: self.func(
 606            f"{'TRY_' if e.args.get('safe') else ''}TO_TIME", e.this, self.format_time(e)
 607        ),
 608        exp.Unhex: rename_func("HEX_DECODE_BINARY"),
 609        exp.UnixToTime: lambda self, e: self.func("TO_TIMESTAMP", e.this, e.args.get("scale")),
 610        exp.Uuid: rename_func("UUID_STRING"),
 611        exp.VarMap: lambda self, e: var_map_sql(self, e, "OBJECT_CONSTRUCT"),
 612        exp.Booland: rename_func("BOOLAND"),
 613        exp.Boolor: rename_func("BOOLOR"),
 614        exp.WeekOfYear: rename_func("WEEKISO"),
 615        exp.YearOfWeek: rename_func("YEAROFWEEK"),
 616        exp.YearOfWeekIso: rename_func("YEAROFWEEKISO"),
 617        exp.Xor: rename_func("BOOLXOR"),
 618        exp.ByteLength: rename_func("OCTET_LENGTH"),
 619        exp.Flatten: rename_func("ARRAY_FLATTEN"),
 620        exp.ArrayConcatAgg: lambda self, e: self.func("ARRAY_FLATTEN", exp.ArrayAgg(this=e.this)),
 621        exp.SHA2Digest: lambda self, e: self.func(
 622            "SHA2_BINARY", e.this, e.args.get("length") or exp.Literal.number(256)
 623        ),
 624    }
 625
 626    def dynamicidentifier_sql(self, expression: exp.DynamicIdentifier) -> str:
 627        this = self.func("IDENTIFIER", expression.this)
 628        if "expressions" in expression.args:
 629            # `IDENTIFIER(...)` invoked as a function, e.g. `IDENTIFIER('my_func')(1, 2)`
 630            return self.func(this, *expression.expressions, normalize=False)
 631        return this
 632
 633    SUPPORTED_JSON_PATH_PARTS = {
 634        exp.JSONPathKey,
 635        exp.JSONPathRoot,
 636        exp.JSONPathSubscript,
 637    }
 638
 639    TYPE_MAPPING = {
 640        **generator.Generator.TYPE_MAPPING,
 641        exp.DType.BIGDECIMAL: "DOUBLE",
 642        exp.DType.JSON: "VARIANT",
 643        exp.DType.NESTED: "OBJECT",
 644        exp.DType.STRUCT: "OBJECT",
 645        exp.DType.TEXT: "VARCHAR",
 646    }
 647
 648    TOKEN_MAPPING = {
 649        TokenType.AUTO_INCREMENT: "AUTOINCREMENT",
 650    }
 651
 652    PROPERTIES_LOCATION = {
 653        **generator.Generator.PROPERTIES_LOCATION,
 654        exp.CredentialsProperty: exp.Properties.Location.POST_WITH,
 655        exp.InteractiveProperty: exp.Properties.Location.POST_CREATE,
 656        exp.LocationProperty: exp.Properties.Location.POST_WITH,
 657        exp.PartitionedByProperty: exp.Properties.Location.POST_SCHEMA,
 658        exp.RowAccessProperty: exp.Properties.Location.POST_SCHEMA,
 659        exp.SetProperty: exp.Properties.Location.UNSUPPORTED,
 660        exp.VolatileProperty: exp.Properties.Location.UNSUPPORTED,
 661    }
 662
 663    UNSUPPORTED_VALUES_EXPRESSIONS: t.ClassVar = {
 664        exp.Map,
 665        exp.StarMap,
 666        exp.Struct,
 667        exp.VarMap,
 668    }
 669
 670    RESPECT_IGNORE_NULLS_UNSUPPORTED_EXPRESSIONS = (exp.ArrayAgg,)
 671
 672    def with_properties(self, properties: exp.Properties) -> str:
 673        return self.properties(properties, wrapped=False, prefix=self.sep(""), sep=" ")
 674
 675    def values_sql(self, expression: exp.Values, values_as_table: bool = True) -> str:
 676        if expression.find(*self.UNSUPPORTED_VALUES_EXPRESSIONS):
 677            values_as_table = False
 678
 679        return super().values_sql(expression, values_as_table=values_as_table)
 680
 681    def datatype_sql(self, expression: exp.DataType) -> str:
 682        # Check if this is a FLOAT type nested inside a VECTOR type
 683        # VECTOR only accepts FLOAT (not DOUBLE), INT, and STRING as element types
 684        # https://docs.snowflake.com/en/sql-reference/data-types-vector
 685        if expression.is_type(exp.DType.DOUBLE):
 686            parent = expression.parent
 687            if isinstance(parent, exp.DataType) and parent.is_type(exp.DType.VECTOR):
 688                # Preserve FLOAT for VECTOR types instead of mapping to synonym DOUBLE
 689                return "FLOAT"
 690
 691        expressions = expression.expressions
 692        if expressions and expression.is_type(*exp.DataType.STRUCT_TYPES):
 693            for field_type in expressions:
 694                # The correct syntax is OBJECT [ (<key> <value_type [NOT NULL] [, ...]) ]
 695                if isinstance(field_type, exp.DataType):
 696                    return "OBJECT"
 697                if (
 698                    isinstance(field_type, exp.ColumnDef)
 699                    and field_type.this
 700                    and field_type.this.is_string
 701                ):
 702                    # Doing OBJECT('foo' VARCHAR) is invalid snowflake Syntax. Moreover, besides
 703                    # converting 'foo' into an identifier, we also need to quote it because these
 704                    # keys are case-sensitive. For example:
 705                    #
 706                    # WITH t AS (SELECT OBJECT_CONSTRUCT('x', 'y') AS c) SELECT c:x FROM t -- correct
 707                    # WITH t AS (SELECT OBJECT_CONSTRUCT('x', 'y') AS c) SELECT c:X FROM t -- incorrect, returns NULL
 708                    field_type.this.replace(exp.to_identifier(field_type.name, quoted=True))
 709
 710        return super().datatype_sql(expression)
 711
 712    def tonumber_sql(self, expression: exp.ToNumber) -> str:
 713        precision = expression.args.get("precision")
 714        scale = expression.args.get("scale")
 715
 716        default_precision = isinstance(precision, exp.Literal) and precision.name == "38"
 717        default_scale = isinstance(scale, exp.Literal) and scale.name == "0"
 718
 719        if default_precision and default_scale:
 720            precision = None
 721            scale = None
 722        elif default_scale:
 723            scale = None
 724
 725        func_name = "TRY_TO_NUMBER" if expression.args.get("safe") else "TO_NUMBER"
 726
 727        return self.func(
 728            func_name,
 729            expression.this,
 730            expression.args.get("format"),
 731            precision,
 732            scale,
 733        )
 734
 735    def timestampfromparts_sql(self, expression: exp.TimestampFromParts) -> str:
 736        milli = expression.args.get("milli")
 737        if milli is not None:
 738            milli_to_nano = milli.pop() * exp.Literal.number(1000000)
 739            expression.set("nano", milli_to_nano)
 740
 741        return rename_func("TIMESTAMP_FROM_PARTS")(self, expression)
 742
 743    def cast_sql(self, expression: exp.Cast, safe_prefix: str | None = None) -> str:
 744        if expression.is_type(exp.DType.GEOGRAPHY):
 745            return self.func("TO_GEOGRAPHY", expression.this)
 746        if expression.is_type(exp.DType.GEOMETRY):
 747            return self.func("TO_GEOMETRY", expression.this)
 748
 749        return super().cast_sql(expression, safe_prefix=safe_prefix)
 750
 751    def trycast_sql(self, expression: exp.TryCast) -> str:
 752        value = expression.this
 753
 754        if value.type is None:
 755            from sqlglot.optimizer.annotate_types import annotate_types
 756
 757            value = annotate_types(value, dialect=self.dialect)
 758
 759        # Snowflake requires that TRY_CAST's value be a string
 760        # If TRY_CAST is being roundtripped (since Snowflake is the only dialect that sets "requires_string") or
 761        # if we can deduce that the value is a string, then we can generate TRY_CAST
 762        if expression.args.get("requires_string") or value.is_type(*exp.DataType.TEXT_TYPES):
 763            return super().trycast_sql(expression)
 764
 765        return self.cast_sql(expression)
 766
 767    def log_sql(self, expression: exp.Log) -> str:
 768        if not expression.expression:
 769            return self.func("LN", expression.this)
 770
 771        return super().log_sql(expression)
 772
 773    def greatest_sql(self, expression: exp.Greatest) -> str:
 774        name = "GREATEST_IGNORE_NULLS" if expression.args.get("ignore_nulls") else "GREATEST"
 775        return self.func(name, expression.this, *expression.expressions)
 776
 777    def least_sql(self, expression: exp.Least) -> str:
 778        name = "LEAST_IGNORE_NULLS" if expression.args.get("ignore_nulls") else "LEAST"
 779        return self.func(name, expression.this, *expression.expressions)
 780
 781    def generator_sql(self, expression: exp.Generator) -> str:
 782        args = []
 783        rowcount = expression.args.get("rowcount")
 784        timelimit = expression.args.get("timelimit")
 785
 786        if rowcount:
 787            args.append(exp.Kwarg(this=exp.var("ROWCOUNT"), expression=rowcount))
 788        if timelimit:
 789            args.append(exp.Kwarg(this=exp.var("TIMELIMIT"), expression=timelimit))
 790
 791        return self.func("GENERATOR", *args)
 792
 793    def unnest_sql(self, expression: exp.Unnest) -> str:
 794        unnest_alias = expression.args.get("alias")
 795        offset = expression.args.get("offset")
 796
 797        unnest_alias_columns = unnest_alias.columns if unnest_alias else []
 798        value = seq_get(unnest_alias_columns, 0) or exp.to_identifier("value")
 799
 800        columns = [
 801            exp.to_identifier("seq"),
 802            exp.to_identifier("key"),
 803            exp.to_identifier("path"),
 804            offset.pop() if isinstance(offset, exp.Expr) else exp.to_identifier("index"),
 805            value,
 806            exp.to_identifier("this"),
 807        ]
 808
 809        if unnest_alias:
 810            unnest_alias.set("columns", columns)
 811        else:
 812            unnest_alias = exp.TableAlias(this="_u", columns=columns)
 813
 814        table_input = self.sql(expression.expressions[0])
 815        if not table_input.startswith("INPUT =>"):
 816            table_input = f"INPUT => {table_input}"
 817
 818        expression_parent = expression.parent
 819
 820        explode = (
 821            f"FLATTEN({table_input})"
 822            if isinstance(expression_parent, exp.Lateral)
 823            else f"TABLE(FLATTEN({table_input}))"
 824        )
 825        alias = self.sql(unnest_alias)
 826        alias = f" AS {alias}" if alias else ""
 827        value = (
 828            ""
 829            if isinstance(expression_parent, (exp.From, exp.Join, exp.Lateral))
 830            else f"{value} FROM "
 831        )
 832
 833        return f"{value}{explode}{alias}"
 834
 835    def undrop_sql(self, expression: exp.Undrop) -> str:
 836        this = self.sql(expression, "this")
 837        kind = expression.kind
 838        rename = self.sql(expression, "rename")
 839        rename = f" RENAME TO {rename}" if rename else ""
 840        return f"UNDROP {kind} {this}{rename}"
 841
 842    def show_sql(self, expression: exp.Show) -> str:
 843        terse = "TERSE " if expression.args.get("terse") else ""
 844        iceberg = "ICEBERG " if expression.args.get("iceberg") else ""
 845        history = " HISTORY" if expression.args.get("history") else ""
 846        like = self.sql(expression, "like")
 847        like = f" LIKE {like}" if like else ""
 848
 849        scope = self.sql(expression, "scope")
 850        scope = f" {scope}" if scope else ""
 851
 852        scope_kind = self.sql(expression, "scope_kind")
 853        if scope_kind:
 854            scope_kind = f" IN {scope_kind}"
 855
 856        starts_with = self.sql(expression, "starts_with")
 857        if starts_with:
 858            starts_with = f" STARTS WITH {starts_with}"
 859
 860        limit = self.sql(expression, "limit")
 861
 862        from_ = self.sql(expression, "from_")
 863        if from_:
 864            from_ = f" FROM {from_}"
 865
 866        privileges = self.expressions(expression, key="privileges", flat=True)
 867        privileges = f" WITH PRIVILEGES {privileges}" if privileges else ""
 868
 869        return f"SHOW {terse}{iceberg}{expression.name}{history}{like}{scope_kind}{scope}{starts_with}{limit}{from_}{privileges}"
 870
 871    def rowaccessproperty_sql(self, expression: exp.RowAccessProperty) -> str:
 872        if not expression.this:
 873            return "ROW ACCESS"
 874        on = f" ON ({self.expressions(expression, flat=True)})" if expression.expressions else ""
 875        return f"WITH ROW ACCESS POLICY {self.sql(expression, 'this')}{on}"
 876
 877    def describe_sql(self, expression: exp.Describe) -> str:
 878        kind_value = expression.args.get("kind") or "TABLE"
 879
 880        properties = expression.args.get("properties")
 881        if properties:
 882            qualifier = self.expressions(properties, sep=" ")
 883            kind = f" {qualifier} {kind_value}"
 884        else:
 885            kind = f" {kind_value}"
 886
 887        this = f" {self.sql(expression, 'this')}"
 888        expressions = self.expressions(expression, flat=True)
 889        expressions = f" {expressions}" if expressions else ""
 890        return f"DESCRIBE{kind}{this}{expressions}"
 891
 892    def generatedasidentitycolumnconstraint_sql(
 893        self, expression: exp.GeneratedAsIdentityColumnConstraint
 894    ) -> str:
 895        start = expression.args.get("start")
 896        start = f" START {start}" if start else ""
 897        increment = expression.args.get("increment")
 898        increment = f" INCREMENT {increment}" if increment else ""
 899
 900        order = expression.args.get("order")
 901        if order is not None:
 902            order_clause = " ORDER" if order else " NOORDER"
 903        else:
 904            order_clause = ""
 905
 906        return f"AUTOINCREMENT{start}{increment}{order_clause}"
 907
 908    def struct_sql(self, expression: exp.Struct) -> str:
 909        if len(expression.expressions) == 1:
 910            arg = expression.expressions[0]
 911            if arg.is_star or (isinstance(arg, exp.ILike) and arg.left.is_star):
 912                # Wildcard syntax: https://docs.snowflake.com/en/sql-reference/data-types-semistructured#object
 913                return f"{{{self.sql(expression.expressions[0])}}}"
 914
 915        keys = []
 916        values = []
 917
 918        for i, e in enumerate(expression.expressions):
 919            if isinstance(e, exp.PropertyEQ):
 920                keys.append(
 921                    exp.Literal.string(e.name) if isinstance(e.this, exp.Identifier) else e.this
 922                )
 923                values.append(e.expression)
 924            else:
 925                keys.append(exp.Literal.string(f"_{i}"))
 926                values.append(e)
 927
 928        return self.func("OBJECT_CONSTRUCT", *flatten(zip(keys, values)))
 929
 930    @unsupported_args("weight", "accuracy")
 931    def approxquantile_sql(self, expression: exp.ApproxQuantile) -> str:
 932        return self.func("APPROX_PERCENTILE", expression.this, expression.args.get("quantile"))
 933
 934    def alterset_sql(self, expression: exp.AlterSet) -> str:
 935        exprs = self.expressions(expression, flat=True)
 936        exprs = f" {exprs}" if exprs else ""
 937        file_format = self.expressions(expression, key="file_format", flat=True, sep=" ")
 938        file_format = f" STAGE_FILE_FORMAT = ({file_format})" if file_format else ""
 939        copy_options = self.expressions(expression, key="copy_options", flat=True, sep=" ")
 940        copy_options = f" STAGE_COPY_OPTIONS = ({copy_options})" if copy_options else ""
 941        tag = self.expressions(expression, key="tag", flat=True)
 942        tag = f" TAG {tag}" if tag else ""
 943
 944        return f"SET{exprs}{file_format}{copy_options}{tag}"
 945
 946    def strtotime_sql(self, expression: exp.StrToTime):
 947        # target_type is stored as a DataType instance
 948        target_type = expression.args.get("target_type")
 949
 950        # Get the type enum from DataType instance or from type annotation
 951        if isinstance(target_type, exp.DataType):
 952            type_enum = target_type.this
 953        elif expression.type:
 954            type_enum = expression.type.this
 955        else:
 956            type_enum = exp.DType.TIMESTAMP
 957
 958        func_name = TIMESTAMP_TYPES.get(type_enum, "TO_TIMESTAMP")
 959
 960        return self.func(
 961            f"{'TRY_' if expression.args.get('safe') else ''}{func_name}",
 962            expression.this,
 963            self.format_time(expression),
 964        )
 965
 966    def timestampsub_sql(self, expression: exp.TimestampSub):
 967        return self.sql(
 968            exp.TimestampAdd(
 969                this=expression.this,
 970                expression=expression.expression * -1,
 971                unit=expression.unit,
 972            )
 973        )
 974
 975    def jsonextract_sql(self, expression: exp.JSONExtract):
 976        this = expression.this
 977
 978        # JSON strings are valid coming from other dialects such as BQ so
 979        # for these cases we PARSE_JSON preemptively
 980        if not isinstance(this, (exp.ParseJSON, exp.JSONExtract)) and not expression.args.get(
 981            "requires_json"
 982        ):
 983            this = exp.ParseJSON(this=this)
 984
 985        return self.func(
 986            "GET_PATH",
 987            this,
 988            expression.expression,
 989        )
 990
 991    def timetostr_sql(self, expression: exp.TimeToStr) -> str:
 992        this = expression.this
 993        if this.is_string:
 994            this = exp.cast(this, exp.DType.TIMESTAMP)
 995
 996        return self.func("TO_CHAR", this, self.format_time(expression))
 997
 998    def datesub_sql(self, expression: exp.DateSub) -> str:
 999        value = expression.expression
1000        if value:
1001            value.replace(value * (-1))
1002        else:
1003            self.unsupported("DateSub cannot be transpiled if the subtracted count is unknown")
1004
1005        return date_delta_sql("DATEADD")(self, expression)
1006
1007    def select_sql(self, expression: exp.Select) -> str:
1008        limit = expression.args.get("limit")
1009        offset = expression.args.get("offset")
1010        if offset and (not limit or (isinstance(limit, exp.Limit) and limit.is_limit_all)):
1011            expression.limit(exp.Null(), copy=False)
1012        return super().select_sql(expression)
1013
1014    def createable_sql(self, expression: exp.Create, locations: defaultdict) -> str:
1015        is_materialized = expression.find(exp.MaterializedProperty)
1016        grants_property = expression.find(exp.CopyGrantsProperty, exp.IgnoreGrantsProperty)
1017
1018        if expression.kind == "VIEW" and is_materialized and grants_property:
1019            # Materialized views require COPY/IGNORE GRANTS before the column list,
1020            # whereas normal views use the default POST_SCHEMA location.
1021            # ref: https://docs.snowflake.com/en/sql-reference/sql/create-materialized-view#syntax
1022            # ref: https://docs.snowflake.com/en/sql-reference/sql/create-view#syntax
1023            post_schema_properties = locations[exp.Properties.Location.POST_SCHEMA]
1024            post_schema_properties.pop(post_schema_properties.index(grants_property))
1025
1026            this_name = self.sql(expression.this, "this")
1027            grants = self.sql(grants_property)
1028            this_schema = self.schema_columns_sql(expression.this)
1029            this_schema = f"{self.sep()}{this_schema}" if this_schema else ""
1030
1031            return f"{this_name}{self.sep()}{grants}{this_schema}"
1032
1033        return super().createable_sql(expression, locations)
1034
1035    def arrayagg_sql(self, expression: exp.ArrayAgg) -> str:
1036        this = expression.this
1037
1038        # If an ORDER BY clause is present, we need to remove it from ARRAY_AGG
1039        # and add it later as part of the WITHIN GROUP clause
1040        order = this if isinstance(this, exp.Order) else None
1041        if order:
1042            expression.set("this", order.this.pop())
1043
1044        expr_sql = super().arrayagg_sql(expression)
1045
1046        if order:
1047            expr_sql = self.sql(exp.WithinGroup(this=expr_sql, expression=order))
1048
1049        return expr_sql
1050
1051    def arraydistinct_sql(self, expression: exp.ArrayDistinct) -> str:
1052        if expression.args.get("check_null"):
1053            return self.func("ARRAY_DISTINCT", expression.this)
1054        return self.func("ARRAY_DISTINCT", exp.ArrayCompact(this=expression.this))
1055
1056    def arraytostring_sql(self, expression: exp.ArrayToString) -> str:
1057        return self.func("ARRAY_TO_STRING", expression.this, expression.expression)
1058
1059    def array_sql(self, expression: exp.Array) -> str:
1060        expressions = expression.expressions
1061
1062        first_expr = seq_get(expressions, 0)
1063        if isinstance(first_expr, exp.Select):
1064            # SELECT AS STRUCT foo AS alias_foo -> ARRAY_AGG(OBJECT_CONSTRUCT('alias_foo', foo))
1065            if first_expr.text("kind").upper() == "STRUCT":
1066                object_construct_args = []
1067                for expr in first_expr.expressions:
1068                    # Alias case: SELECT AS STRUCT foo AS alias_foo -> OBJECT_CONSTRUCT('alias_foo', foo)
1069                    # Column case: SELECT AS STRUCT foo -> OBJECT_CONSTRUCT('foo', foo)
1070                    name = expr.this if isinstance(expr, exp.Alias) else expr
1071
1072                    object_construct_args.extend([exp.Literal.string(expr.alias_or_name), name])
1073
1074                array_agg = exp.ArrayAgg(this=build_object_construct(args=object_construct_args))
1075
1076                first_expr.set("kind", None)
1077                first_expr.set("expressions", [array_agg])
1078
1079                return self.sql(first_expr.subquery())
1080
1081        return inline_array_sql(self, expression)
1082
1083    def currentdate_sql(self, expression: exp.CurrentDate) -> str:
1084        zone = self.sql(expression, "this")
1085        if not zone:
1086            return super().currentdate_sql(expression)
1087
1088        expr = exp.Cast(
1089            this=exp.ConvertTimezone(target_tz=zone, timestamp=exp.CurrentTimestamp()),
1090            to=exp.DataType(this=exp.DType.DATE),
1091        )
1092        return self.sql(expr)
1093
1094    def dot_sql(self, expression: exp.Dot) -> str:
1095        this = expression.this
1096
1097        if not this.type:
1098            from sqlglot.optimizer.annotate_types import annotate_types
1099
1100            this = annotate_types(this, dialect=self.dialect)
1101
1102        if not isinstance(this, exp.Dot) and this.is_type(exp.DType.STRUCT):
1103            # Generate colon notation for the top level STRUCT
1104            return f"{self.sql(this)}:{self.sql(expression, 'expression')}"
1105
1106        return super().dot_sql(expression)
1107
1108    def modelattribute_sql(self, expression: exp.ModelAttribute) -> str:
1109        return f"{self.sql(expression, 'this')}!{self.sql(expression, 'expression')}"
1110
1111    def format_sql(self, expression: exp.Format) -> str:
1112        if expression.name.lower() == "%s" and len(expression.expressions) == 1:
1113            return self.func("TO_CHAR", expression.expressions[0])
1114
1115        return self.function_fallback_sql(expression)
1116
1117    def splitpart_sql(self, expression: exp.SplitPart) -> str:
1118        # Set part_index to 1 if missing
1119        if not expression.args.get("delimiter"):
1120            expression.set("delimiter", exp.Literal.string(" "))
1121
1122        if not expression.args.get("part_index"):
1123            expression.set("part_index", exp.Literal.number(1))
1124
1125        return rename_func("SPLIT_PART")(self, expression)
1126
1127    def uniform_sql(self, expression: exp.Uniform) -> str:
1128        gen = expression.args.get("gen")
1129        seed = expression.args.get("seed")
1130
1131        # From Databricks UNIFORM(min, max, seed) -> Wrap gen in RANDOM(seed)
1132        if seed:
1133            gen = exp.Rand(this=seed)
1134
1135        # No gen argument (from Databricks 2-arg UNIFORM(min, max)) -> Add RANDOM()
1136        if not gen:
1137            gen = exp.Rand()
1138
1139        return self.func("UNIFORM", expression.this, expression.expression, gen)
1140
1141    def window_sql(self, expression: exp.Window) -> str:
1142        spec = expression.args.get("spec")
1143        this = expression.this
1144
1145        if (
1146            (
1147                isinstance(this, RANKING_WINDOW_FUNCTIONS_WITH_FRAME)
1148                or (
1149                    isinstance(this, (exp.RespectNulls, exp.IgnoreNulls))
1150                    and isinstance(this.this, RANKING_WINDOW_FUNCTIONS_WITH_FRAME)
1151                )
1152            )
1153            and spec
1154            and (
1155                spec.text("kind").upper() == "ROWS"
1156                and spec.text("start").upper() == "UNBOUNDED"
1157                and spec.text("start_side").upper() == "PRECEDING"
1158                and spec.text("end").upper() == "UNBOUNDED"
1159                and spec.text("end_side").upper() == "FOLLOWING"
1160            )
1161        ):
1162            # omit the default window from window ranking functions
1163            expression.set("spec", None)
1164        return super().window_sql(expression)
1165
1166    def withingroup_sql(self, expression: exp.WithinGroup) -> str:
1167        # Snowflake's MODE doesn't support the ordered-set syntax, i.e. it only
1168        # accepts the value to aggregate as an argument: MODE(<expr>)
1169        if isinstance(expression.this, exp.Mode) and not expression.this.this:
1170            order = expression.expression
1171            if isinstance(order, exp.Order) and len(order.expressions) == 1:
1172                return self.sql(exp.Mode(this=order.expressions[0].this))
1173
1174        return super().withingroup_sql(expression)