sqlglot.generators.tsql

  1from __future__ import annotations
  2
  3from functools import reduce
  4
  5from sqlglot import exp, generator, transforms
  6from sqlglot.dialects.dialect import (
  7    any_value_to_max_sql,
  8    date_delta_sql,
  9    datestrtodate_sql,
 10    generatedasidentitycolumnconstraint_sql,
 11    max_or_greatest,
 12    min_or_least,
 13    no_filter_sql,
 14    remove_ts_or_ds_to_date,
 15    rename_func,
 16    strposition_sql,
 17    timestrtotime_sql,
 18    trim_sql,
 19)
 20from sqlglot.helper import seq_get
 21from sqlglot.optimizer.scope import find_in_scope
 22from sqlglot.parsers.tsql import OPTIONS_THAT_REQUIRE_EQUAL
 23from sqlglot.time import format_time
 24from collections import defaultdict
 25
 26DATE_PART_UNMAPPING = {
 27    "WEEKISO": "ISO_WEEK",
 28    "DAYOFWEEK": "WEEKDAY",
 29    "TIMEZONE_MINUTE": "TZOFFSET",
 30}
 31
 32BIT_TYPES = {exp.EQ, exp.NEQ, exp.Is, exp.In, exp.Select, exp.Alias}
 33
 34SET_OP_MODIFIERS = ("limit", "offset", "order", "for_", "options")
 35
 36
 37def _format_sql(self: TSQLGenerator, expression: exp.NumberToStr | exp.TimeToStr) -> str:
 38    fmt = expression.args["format"]
 39
 40    if not isinstance(expression, exp.NumberToStr):
 41        if fmt.is_string:
 42            from sqlglot.dialects.tsql import TSQL
 43
 44            mapped_fmt = format_time(fmt.name, TSQL.INVERSE_TIME_MAPPING)
 45            fmt_sql = self.sql(exp.Literal.string(mapped_fmt))
 46        else:
 47            fmt_sql = self.format_time(expression) or self.sql(fmt)
 48    else:
 49        fmt_sql = self.sql(fmt)
 50
 51    return self.func("FORMAT", expression.this, fmt_sql, expression.args.get("culture"))
 52
 53
 54def _string_agg_sql(self: TSQLGenerator, expression: exp.GroupConcat) -> str:
 55    this = expression.this
 56    distinct = find_in_scope(expression, exp.Distinct)
 57    if distinct:
 58        # exp.Distinct can appear below an exp.Order or an exp.GroupConcat expression
 59        self.unsupported("T-SQL STRING_AGG doesn't support DISTINCT.")
 60        this = distinct.pop().expressions[0]
 61
 62    order = ""
 63    if isinstance(expression.this, exp.Order):
 64        if expression.this.this:
 65            this = expression.this.this.pop()
 66        # Order has a leading space
 67        order = f" WITHIN GROUP ({self.sql(expression.this)[1:]})"
 68
 69    separator = expression.args.get("separator") or exp.Literal.string(",")
 70    return f"STRING_AGG({self.format_args(this, separator)}){order}"
 71
 72
 73def qualify_derived_table_outputs(expression: exp.Expr) -> exp.Expr:
 74    """Ensures all (unnamed) output columns are aliased for CTEs and Subqueries."""
 75    alias = expression.args.get("alias")
 76
 77    if (
 78        isinstance(expression, (exp.CTE, exp.Subquery))
 79        and isinstance(alias, exp.TableAlias)
 80        and not alias.columns
 81        and isinstance(expression.this, exp.Query)
 82    ):
 83        from sqlglot.dialects.tsql import TSQL
 84        from sqlglot.optimizer.qualify_columns import qualify_outputs
 85
 86        # We keep track of the unaliased column projection indexes instead of the expressions
 87        # themselves, because the latter are going to be replaced by new nodes when the aliases
 88        # are added and hence we won't be able to reach these newly added Alias parents
 89        query = expression.this
 90        unaliased_column_indexes = (
 91            i for i, c in enumerate(query.selects) if isinstance(c, exp.Column) and not c.alias
 92        )
 93
 94        qualify_outputs(query, dialect=TSQL())
 95
 96        # Preserve the quoting information of columns for newly added Alias nodes
 97        query_selects = query.selects
 98        for select_index in unaliased_column_indexes:
 99            alias = query_selects[select_index]
100            column = alias.this
101            if isinstance(column.this, exp.Identifier):
102                alias.args["alias"].set("quoted", column.this.quoted)
103
104    return expression
105
106
107def _json_extract_sql(
108    self: TSQLGenerator, expression: exp.JSONExtract | exp.JSONExtractScalar
109) -> str:
110    # JSON_QUERY returns objects and arrays, JSON_VALUE returns scalars. A scalar-only
111    # extraction maps to JSON_VALUE; a source that also returns non-scalar values as
112    # text (e.g. SQLite's ->>) needs to try both, like a generic JSONExtract does
113    if isinstance(expression, exp.JSONExtractScalar) and expression.args.get("scalar_only"):
114        return self.func("JSON_VALUE", expression.this, expression.expression)
115
116    json_query = self.func("JSON_QUERY", expression.this, expression.expression)
117    if expression.args.get("json_query"):
118        return json_query
119
120    json_value = self.func("JSON_VALUE", expression.this, expression.expression)
121    return self.func("ISNULL", json_query, json_value)
122
123
124def _timestrtotime_sql(self: TSQLGenerator, expression: exp.TimeStrToTime):
125    sql = timestrtotime_sql(self, expression)
126    if expression.args.get("zone"):
127        # If there is a timezone, produce an expression like:
128        # CAST('2020-01-01 12:13:14-08:00' AS DATETIMEOFFSET) AT TIME ZONE 'UTC'
129        # If you dont have AT TIME ZONE 'UTC', wrapping that expression in another cast back to DATETIME2 just drops the timezone information
130        return self.sql(exp.AtTimeZone(this=sql, zone=exp.Literal.string("UTC")))
131    return sql
132
133
134class TSQLGenerator(generator.Generator):
135    SELECT_KINDS: tuple[str, ...] = ()
136    TRY_SUPPORTED = False
137    SUPPORTS_UESCAPE = False
138    SUPPORTS_DECODE_CASE = False
139
140    AFTER_HAVING_MODIFIER_TRANSFORMS = generator.AFTER_HAVING_MODIFIER_TRANSFORMS
141
142    LIMIT_IS_TOP = True
143    SET_OP_LIMITS = True
144    QUERY_HINTS = False
145    RETURNING_END = False
146    NVL2_SUPPORTED = False
147    ALTER_TABLE_INCLUDE_COLUMN_KEYWORD = False
148    ALTER_TABLE_ADD_COLUMNS_WRAPPED = False
149    LIMIT_FETCH = "FETCH"
150    COMPUTED_COLUMN_WITH_TYPE = False
151    CTE_RECURSIVE_KEYWORD_REQUIRED = False
152    ENSURE_BOOLS = True
153    NULL_ORDERING_SUPPORTED: bool | None = None
154    SUPPORTS_SINGLE_ARG_CONCAT = False
155    TABLESAMPLE_SEED_KEYWORD = "REPEATABLE"
156    SUPPORTS_SELECT_INTO = True
157    JSON_PATH_BRACKETED_KEY_SUPPORTED = False
158    SUPPORTS_TO_NUMBER = False
159    COPY_PARAMS_EQ_REQUIRED = True
160    PARSE_JSON_NAME: str | None = None
161    EXCEPT_INTERSECT_SUPPORT_ALL_CLAUSE = False
162    ALTER_SET_WRAPPED = True
163    ALTER_SET_TYPE = ""
164    SUPPORTS_ALTER_COLUMN_NULLABILITY = True
165
166    EXPRESSIONS_WITHOUT_NESTED_CTES = {
167        exp.Create,
168        exp.Delete,
169        exp.Insert,
170        exp.Intersect,
171        exp.Except,
172        exp.Merge,
173        exp.Select,
174        exp.Subquery,
175        exp.Union,
176        exp.Update,
177    }
178
179    SUPPORTED_JSON_PATH_PARTS = {
180        exp.JSONPathKey,
181        exp.JSONPathRoot,
182        exp.JSONPathSubscript,
183    }
184
185    TYPE_MAPPING = {
186        **{
187            k: v
188            for k, v in generator.Generator.TYPE_MAPPING.items()
189            if k not in (exp.DType.NCHAR, exp.DType.NVARCHAR)
190        },
191        exp.DType.BOOLEAN: "BIT",
192        exp.DType.DATETIME2: "DATETIME2",
193        exp.DType.DECIMAL: "NUMERIC",
194        exp.DType.DOUBLE: "FLOAT",
195        exp.DType.INT: "INTEGER",
196        exp.DType.ROWVERSION: "ROWVERSION",
197        exp.DType.TEXT: "VARCHAR(MAX)",
198        exp.DType.TIMESTAMP: "DATETIME2",
199        exp.DType.TIMESTAMPNTZ: "DATETIME2",
200        exp.DType.TIMESTAMPTZ: "DATETIMEOFFSET",
201        exp.DType.SMALLDATETIME: "SMALLDATETIME",
202        exp.DType.UTINYINT: "TINYINT",
203        exp.DType.VARIANT: "SQL_VARIANT",
204        exp.DType.UUID: "UNIQUEIDENTIFIER",
205    }
206
207    TRANSFORMS = {
208        **{k: v for k, v in generator.Generator.TRANSFORMS.items() if k != exp.ReturnsProperty},
209        exp.AnyValue: any_value_to_max_sql,
210        exp.Atan2: rename_func("ATN2"),
211        exp.ArrayToString: rename_func("STRING_AGG"),
212        exp.AutoIncrementColumnConstraint: lambda *_: "IDENTITY",
213        exp.Ceil: rename_func("CEILING"),
214        exp.Chr: rename_func("CHAR"),
215        exp.DateAdd: date_delta_sql("DATEADD"),
216        exp.CTE: transforms.preprocess([qualify_derived_table_outputs]),
217        exp.CurrentDate: rename_func("GETDATE"),
218        exp.CurrentTimestamp: rename_func("GETDATE"),
219        exp.CurrentTimestampLTZ: rename_func("SYSDATETIMEOFFSET"),
220        exp.DateStrToDate: datestrtodate_sql,
221        exp.Day: remove_ts_or_ds_to_date(),
222        exp.Filter: no_filter_sql,
223        exp.GeneratedAsIdentityColumnConstraint: generatedasidentitycolumnconstraint_sql,
224        exp.GroupConcat: _string_agg_sql,
225        exp.If: rename_func("IIF"),
226        exp.JSONExtract: _json_extract_sql,
227        exp.JSONExtractScalar: _json_extract_sql,
228        exp.LastDay: lambda self, e: self.func("EOMONTH", e.this),
229        exp.Ln: rename_func("LOG"),
230        exp.Max: max_or_greatest,
231        exp.MD5: lambda self, e: self.func("HASHBYTES", exp.Literal.string("MD5"), e.this),
232        exp.Min: min_or_least,
233        exp.Month: remove_ts_or_ds_to_date(),
234        exp.NumberToStr: _format_sql,
235        exp.Repeat: rename_func("REPLICATE"),
236        exp.CurrentSchema: rename_func("SCHEMA_NAME"),
237        exp.Select: transforms.preprocess(
238            [
239                transforms.eliminate_distinct_on,
240                transforms.eliminate_semi_and_anti_joins,
241                transforms.eliminate_qualify,
242                transforms.unnest_generate_date_array_using_recursive_cte,
243            ]
244        ),
245        exp.Stddev: rename_func("STDEV"),
246        exp.StrPosition: lambda self, e: strposition_sql(
247            self, e, func_name="CHARINDEX", supports_position=True
248        ),
249        exp.Subquery: transforms.preprocess([qualify_derived_table_outputs]),
250        exp.SHA: lambda self, e: self.func("HASHBYTES", exp.Literal.string("SHA1"), e.this),
251        exp.SHA1Digest: lambda self, e: self.func("HASHBYTES", exp.Literal.string("SHA1"), e.this),
252        exp.SHA2: lambda self, e: self.func(
253            "HASHBYTES", exp.Literal.string(f"SHA2_{e.args.get('length', 256)}"), e.this
254        ),
255        exp.TemporaryProperty: lambda self, e: "",
256        exp.TimeStrToTime: _timestrtotime_sql,
257        exp.TimeToStr: _format_sql,
258        exp.TimestampAdd: date_delta_sql("DATEADD"),
259        exp.Trim: trim_sql,
260        exp.TsOrDsAdd: date_delta_sql("DATEADD", cast=True),
261        exp.TsOrDsDiff: date_delta_sql("DATEDIFF"),
262        exp.TimestampTrunc: lambda self, e: self.func("DATETRUNC", e.unit, e.this),
263        exp.Trunc: lambda self, e: self.func(
264            "ROUND",
265            e.this,
266            e.args.get("decimals") or exp.Literal.number(0),
267            exp.Literal.number(1),
268        ),
269        exp.Uuid: lambda *_: "NEWID()",
270        exp.Year: remove_ts_or_ds_to_date(),
271        exp.DateFromParts: rename_func("DATEFROMPARTS"),
272    }
273
274    PROPERTIES_LOCATION = {
275        **generator.Generator.PROPERTIES_LOCATION,
276        exp.VolatileProperty: exp.Properties.Location.UNSUPPORTED,
277    }
278
279    def scope_resolution(self, rhs: str, scope_name: str) -> str:
280        return f"{scope_name}::{rhs}"
281
282    def select_sql(self, expression: exp.Select) -> str:
283        self._prepare_limit_offset(expression)
284
285        # Handles transpiling a query like the following to T-SQL:
286        #   SELECT 1 AS x ORDER BY x NULLS FIRST FETCH FIRST 1 ROWS ONLY UNION ALL SELECT 2 AS x
287        if isinstance(expression.parent, exp.SetOperation) and isinstance(
288            expression.args.get("limit"), exp.Fetch
289        ):
290            return self.sql(
291                exp.select("*").from_(expression.subquery("_l_0", copy=False), copy=False)
292            )
293
294        return super().select_sql(expression)
295
296    def set_operations(self, expression: exp.SetOperation) -> str:
297        limit = expression.args.get("limit")
298        offset = expression.args.get("offset")
299        order = expression.args.get("order")
300
301        # Set operations cannot order by the CASE used to emulate null ordering,
302        # or by expressions that aren't in their select list.
303        wrap_order = False
304        if order:
305            selects = {select.unalias().unnest() for select in expression.selects}
306            for ordered in order.expressions:
307                this = ordered.this.unnest()
308                if this.is_int:
309                    continue
310
311                desc = ordered.args.get("desc")
312                nulls_first = ordered.args.get("nulls_first")
313
314                emulate_null_ordering = (desc and nulls_first) or (not desc and not nulls_first)
315                if emulate_null_ordering or (
316                    not isinstance(this, exp.Column) and this not in selects
317                ):
318                    wrap_order = True
319                    break
320
321        if (
322            wrap_order
323            or (isinstance(limit, exp.Limit) and not offset)
324            or (not order and (offset or isinstance(limit, exp.Fetch)))
325        ):
326            select = self._move_ctes_to_top_level(
327                exp.subquery(expression, "_l_0", copy=False).select("*", copy=False)
328            )
329            for arg in SET_OP_MODIFIERS:
330                value = expression.args.get(arg)
331                if value:
332                    expression.set(arg, None)
333                    select.set(arg, value)
334
335            return self.sql(select)
336
337        self._prepare_limit_offset(expression)
338        return super().set_operations(expression)
339
340    def _prepare_limit_offset(self, expression: exp.Query) -> None:
341        limit = expression.args.get("limit")
342        offset = expression.args.get("offset")
343
344        if isinstance(limit, exp.Fetch) and not offset:
345            # Dialects like Oracle can FETCH directly from a row set but
346            # T-SQL requires an ORDER BY + OFFSET clause in order to FETCH
347            offset = exp.Offset(expression=exp.Literal.number(0))
348            expression.set("offset", offset)
349
350        if offset:
351            if not expression.args.get("order"):
352                # ORDER BY is required in order to use OFFSET in a query, so we use
353                # a noop order by, since we don't really care about the order.
354                # See: https://www.microsoftpressstore.com/articles/article.aspx?p=2314819
355                expression.order_by(exp.select(exp.null()).subquery(), copy=False)
356
357            if isinstance(limit, exp.Limit) and not limit.is_limit_all:
358                # TOP and OFFSET can't be combined, we need use FETCH instead of TOP
359                # we replace here because otherwise TOP would be generated in select_sql
360                limit.replace(exp.Fetch(direction="FIRST", count=limit.expression))
361
362    def convert_sql(self, expression: exp.Convert) -> str:
363        name = "TRY_CONVERT" if expression.args.get("safe") else "CONVERT"
364        return self.func(name, expression.this, expression.expression, expression.args.get("style"))
365
366    def queryoption_sql(self, expression: exp.QueryOption) -> str:
367        option = self.sql(expression, "this")
368        value = self.sql(expression, "expression")
369        if value:
370            optional_equal_sign = "= " if option in OPTIONS_THAT_REQUIRE_EQUAL else ""
371            return f"{option} {optional_equal_sign}{value}"
372        return option
373
374    def lateral_op(self, expression: exp.Lateral) -> str:
375        cross_apply = expression.args.get("cross_apply")
376        if cross_apply is True:
377            return "CROSS APPLY"
378        if cross_apply is False:
379            return "OUTER APPLY"
380
381        # TODO: perhaps we can check if the parent is a Join and transpile it appropriately
382        self.unsupported("LATERAL clause is not supported.")
383        return "LATERAL"
384
385    def splitpart_sql(self, expression: exp.SplitPart) -> str:
386        this = expression.this
387        split_count = len(this.name.split("."))
388        delimiter = expression.args.get("delimiter")
389        part_index = expression.args.get("part_index")
390
391        if (
392            not all(isinstance(arg, exp.Literal) for arg in (this, delimiter, part_index))
393            or (delimiter and delimiter.name != ".")
394            or not part_index
395            or split_count > 4
396        ):
397            self.unsupported(
398                "SPLIT_PART can be transpiled to PARSENAME only for '.' delimiter and literal values"
399            )
400            return ""
401
402        return self.func(
403            "PARSENAME", this, exp.Literal.number(split_count + 1 - part_index.to_py())
404        )
405
406    def extract_sql(self, expression: exp.Extract) -> str:
407        part = expression.this
408        name = DATE_PART_UNMAPPING.get(part.name.upper()) or part
409
410        return self.func("DATEPART", name, expression.expression)
411
412    def timefromparts_sql(self, expression: exp.TimeFromParts) -> str:
413        nano = expression.args.get("nano")
414        if nano is not None:
415            nano.pop()
416            self.unsupported("Specifying nanoseconds is not supported in TIMEFROMPARTS.")
417
418        if expression.args.get("fractions") is None:
419            expression.set("fractions", exp.Literal.number(0))
420        if expression.args.get("precision") is None:
421            expression.set("precision", exp.Literal.number(0))
422
423        return rename_func("TIMEFROMPARTS")(self, expression)
424
425    def timestampfromparts_sql(self, expression: exp.TimestampFromParts) -> str:
426        zone = expression.args.get("zone")
427        if zone is not None:
428            zone.pop()
429            self.unsupported("Time zone is not supported in DATETIMEFROMPARTS.")
430
431        nano = expression.args.get("nano")
432        if nano is not None:
433            nano.pop()
434            self.unsupported("Specifying nanoseconds is not supported in DATETIMEFROMPARTS.")
435
436        if expression.args.get("milli") is None:
437            expression.set("milli", exp.Literal.number(0))
438
439        return rename_func("DATETIMEFROMPARTS")(self, expression)
440
441    def setitem_sql(self, expression: exp.SetItem) -> str:
442        this = expression.this
443        if isinstance(this, exp.EQ) and not isinstance(this.left, exp.Parameter):
444            # T-SQL does not use '=' in SET command, except when the LHS is a variable.
445            return f"{self.sql(this.left)} {self.sql(this.right)}"
446
447        return super().setitem_sql(expression)
448
449    def boolean_sql(self, expression: exp.Boolean) -> str:
450        if type(expression.parent) in BIT_TYPES or isinstance(
451            expression.find_ancestor(exp.Values, exp.Select), exp.Values
452        ):
453            return "1" if expression.this else "0"
454
455        return "(1 = 1)" if expression.this else "(1 = 0)"
456
457    def is_sql(self, expression: exp.Is) -> str:
458        negate = expression.args.get("negate")
459        if isinstance(expression.expression, exp.Boolean):
460            return self.binary(expression, "<>" if negate else "=")
461        return self.binary(expression, "IS NOT" if negate else "IS")
462
463    def createable_sql(self, expression: exp.Create, locations: defaultdict) -> str:
464        sql = self.sql(expression, "this")
465        properties = expression.args.get("properties")
466
467        start = self._identifier_start
468        if (
469            not sql.startswith("#")
470            and not sql.startswith(f"{start}#")
471            and any(
472                isinstance(prop, exp.TemporaryProperty)
473                for prop in (properties.expressions if properties else [])
474            )
475        ):
476            sql = f"{start}#{sql[len(start) :]}" if sql.startswith(start) else f"#{sql}"
477
478        return sql
479
480    def create_sql(self, expression: exp.Create) -> str:
481        kind = expression.kind
482        exists = expression.args.get("exists")
483        expression.set("exists", None)
484
485        like_property = expression.find(exp.LikeProperty)
486        if like_property:
487            ctas_expression = like_property.this
488        else:
489            ctas_expression = expression.expression
490
491        if kind == "VIEW":
492            expression.this.set("catalog", None)
493            with_ = expression.args.get("with_")
494            if ctas_expression and with_:
495                # We've already preprocessed the Create expression to bubble up any nested CTEs,
496                # but CREATE VIEW actually requires the WITH clause to come after it so we need
497                # to amend the AST by moving the CTEs to the CREATE VIEW statement's query.
498                ctas_expression.set("with_", with_.pop())
499        elif (
500            kind == "FUNCTION"
501            and isinstance(ctas_expression, exp.Return)
502            and isinstance(body := ctas_expression.this.unnest(), exp.Query)
503            and (with_ := expression.args.get("with_"))
504        ):
505            # Similar to the VIEW branch, the table-valued functions require the WITH clause
506            # to stay inside the RETURN body, so we move back any CTEs that were bubbled up.
507            body.set("with_", with_.pop())
508
509        table = expression.find(exp.Table)
510
511        # Convert CTAS statement to SELECT .. INTO ..
512        if kind == "TABLE" and ctas_expression:
513            if isinstance(ctas_expression, exp.UNWRAPPED_QUERIES):
514                ctas_expression = ctas_expression.subquery()
515
516            properties = expression.args.get("properties") or exp.Properties()
517            is_temp = any(isinstance(p, exp.TemporaryProperty) for p in properties.expressions)
518
519            select_into = exp.select("*").from_(exp.alias_(ctas_expression, "temp", table=True))
520            select_into.set("into", exp.Into(this=table, temporary=is_temp))
521
522            if like_property:
523                select_into.limit(0, copy=False)
524
525            sql = self.sql(select_into)
526        else:
527            sql = super().create_sql(expression)
528
529        if exists:
530            identifier = self.sql(exp.Literal.string(exp.table_name(table) if table else ""))
531            sql_with_ctes = self.prepend_ctes(expression, sql)
532            sql_literal = self.sql(exp.Literal.string(sql_with_ctes))
533            if kind == "SCHEMA":
534                return f"""IF NOT EXISTS (SELECT * FROM INFORMATION_SCHEMA.SCHEMATA WHERE SCHEMA_NAME = {identifier}) EXEC({sql_literal})"""
535            elif kind == "TABLE":
536                assert table
537                where = exp.and_(
538                    exp.column("TABLE_NAME").eq(table.name),
539                    exp.column("TABLE_SCHEMA").eq(table.db) if table.db else None,
540                    exp.column("TABLE_CATALOG").eq(table.catalog) if table.catalog else None,
541                )
542                return f"""IF NOT EXISTS (SELECT * FROM INFORMATION_SCHEMA.TABLES WHERE {where}) EXEC({sql_literal})"""
543            elif kind == "INDEX":
544                index = self.sql(exp.Literal.string(expression.this.text("this")))
545                return f"""IF NOT EXISTS (SELECT * FROM sys.indexes WHERE object_id = object_id({identifier}) AND name = {index}) EXEC({sql_literal})"""
546        elif expression.args.get("replace"):
547            sql = sql.replace("CREATE OR REPLACE ", "CREATE OR ALTER ", 1)
548
549        return self.prepend_ctes(expression, sql)
550
551    @generator.unsupported_args("unlogged", "expressions")
552    def into_sql(self, expression: exp.Into) -> str:
553        if expression.args.get("temporary"):
554            # If the Into expression has a temporary property, push this down to the Identifier
555            table = expression.find(exp.Table)
556            if table and isinstance(table.this, exp.Identifier):
557                table.this.set("temporary", True)
558
559        return f"{self.seg('INTO')} {self.sql(expression, 'this')}"
560
561    def count_sql(self, expression: exp.Count) -> str:
562        func_name = "COUNT_BIG" if expression.args.get("big_int") else "COUNT"
563        return rename_func(func_name)(self, expression)
564
565    def countif_sql(self, expression: exp.CountIf) -> str:
566        # T-SQL has no COUNT_IF, so count the rows where the predicate holds instead
567        return self.func(
568            "COUNT", exp.If(this=expression.this, true=exp.Literal.number(1), false=exp.null())
569        )
570
571    def datediff_sql(self, expression: exp.DateDiff) -> str:
572        func_name = "DATEDIFF_BIG" if expression.args.get("big_int") else "DATEDIFF"
573        return date_delta_sql(func_name)(self, expression)
574
575    def offset_sql(self, expression: exp.Offset) -> str:
576        return f"{super().offset_sql(expression)} ROWS"
577
578    def version_sql(self, expression: exp.Version) -> str:
579        name = "SYSTEM_TIME" if expression.name == "TIMESTAMP" else expression.name
580        this = f"FOR {name}"
581        expr = expression.expression
582        kind = expression.text("kind")
583        if kind in ("FROM", "BETWEEN"):
584            args = expr.expressions
585            sep = "TO" if kind == "FROM" else "AND"
586            expr_sql = f"{self.sql(seq_get(args, 0))} {sep} {self.sql(seq_get(args, 1))}"
587        else:
588            expr_sql = self.sql(expr)
589
590        expr_sql = f" {expr_sql}" if expr_sql else ""
591        return f"{this} {kind}{expr_sql}"
592
593    def returnsproperty_sql(self, expression: exp.ReturnsProperty) -> str:
594        table = expression.args.get("table")
595        table = f"{table} " if table else ""
596        return f"RETURNS {table}{self.sql(expression, 'this')}"
597
598    def returning_sql(self, expression: exp.Returning) -> str:
599        into = self.sql(expression, "into")
600        into = self.seg(f"INTO {into}") if into else ""
601        return f"{self.seg('OUTPUT')} {self.expressions(expression, flat=True)}{into}"
602
603    def transaction_sql(self, expression: exp.Transaction) -> str:
604        this = self.sql(expression, "this")
605        this = f" {this}" if this else ""
606        mark = self.sql(expression, "mark")
607        mark = f" WITH MARK {mark}" if mark else ""
608        return f"BEGIN TRANSACTION{this}{mark}"
609
610    def commit_sql(self, expression: exp.Commit) -> str:
611        this = self.sql(expression, "this")
612        this = f" {this}" if this else ""
613        durability = expression.args.get("durability")
614        durability = (
615            f" WITH (DELAYED_DURABILITY = {'ON' if durability else 'OFF'})"
616            if durability is not None
617            else ""
618        )
619        return f"COMMIT TRANSACTION{this}{durability}"
620
621    def rollback_sql(self, expression: exp.Rollback) -> str:
622        this = self.sql(expression, "this")
623        this = f" {this}" if this else ""
624        return f"ROLLBACK TRANSACTION{this}"
625
626    def identifier_sql(self, expression: exp.Identifier) -> str:
627        identifier = super().identifier_sql(expression)
628
629        if expression.args.get("global_"):
630            prefix = "##"
631        elif expression.args.get("temporary"):
632            prefix = "#"
633        else:
634            return identifier
635
636        start = self._identifier_start
637        if expression.quoted and identifier.startswith(start):
638            return f"{start}{prefix}{identifier[len(start) :]}"
639
640        return f"{prefix}{identifier}"
641
642    def constraint_sql(self, expression: exp.Constraint) -> str:
643        this = self.sql(expression, "this")
644        expressions = self.expressions(expression, flat=True, sep=" ")
645        return f"CONSTRAINT {this} {expressions}"
646
647    def length_sql(self, expression: exp.Length) -> str:
648        return self._uncast_text(expression, "LEN")
649
650    def right_sql(self, expression: exp.Right) -> str:
651        return self._uncast_text(expression, "RIGHT")
652
653    def left_sql(self, expression: exp.Left) -> str:
654        return self._uncast_text(expression, "LEFT")
655
656    def _uncast_text(self, expression: exp.Expr, name: str) -> str:
657        this = expression.this
658        if isinstance(this, exp.Cast) and this.is_type(exp.DType.TEXT):
659            this_sql = self.sql(this, "this")
660        else:
661            this_sql = self.sql(this)
662        expression_sql = self.sql(expression, "expression")
663        return self.func(name, this_sql, expression_sql if expression_sql else None)
664
665    def partition_sql(self, expression: exp.Partition) -> str:
666        return f"WITH (PARTITIONS({self.expressions(expression, flat=True)}))"
667
668    def alter_sql(self, expression: exp.Alter) -> str:
669        actions = expression.args.get("actions") or []
670        if len(actions) == 1 and isinstance(actions[0], exp.AlterRename):
671            old_name = self.sql(exp.Literal.string(self.sql(expression.this)))
672            new_name = self.sql(exp.Literal.string(actions[0].this.name))
673            return f"EXEC sp_rename {old_name}, {new_name}"
674        return super().alter_sql(expression)
675
676    def drop_sql(self, expression: exp.Drop) -> str:
677        if expression.args["kind"] == "VIEW":
678            for table in expression.args.get("tables") or []:
679                table.set("catalog", None)
680        return super().drop_sql(expression)
681
682    def options_modifier(self, expression: exp.Expr) -> str:
683        options = self.expressions(expression, key="options")
684        return f" OPTION{self.wrap(options)}" if options else ""
685
686    def dpipe_sql(self, expression: exp.DPipe) -> str:
687        return self.sql(reduce(lambda x, y: exp.Add(this=x, expression=y), expression.flatten()))
688
689    def isascii_sql(self, expression: exp.IsAscii) -> str:
690        return f"(PATINDEX(CONVERT(VARCHAR(MAX), 0x255b5e002d7f5d25) COLLATE Latin1_General_BIN, {self.sql(expression.this)}) = 0)"
691
692    def columndef_sql(self, expression: exp.ColumnDef, sep: str = " ") -> str:
693        this = super().columndef_sql(expression, sep)
694        default = self.sql(expression, "default")
695        default = f" = {default}" if default else ""
696        output = self.sql(expression, "output")
697        output = f" {output}" if output else ""
698        return f"{this}{default}{output}"
699
700    def coalesce_sql(self, expression: exp.Coalesce) -> str:
701        func_name = "ISNULL" if expression.args.get("is_null") else "COALESCE"
702        return rename_func(func_name)(self, expression)
703
704    def storedprocedure_sql(self, expression: exp.StoredProcedure) -> str:
705        this = self.sql(expression, "this")
706        expressions = self.expressions(expression)
707        expressions = (
708            self.wrap(expressions) if expression.args.get("wrapped") else f" {expressions}"
709        )
710        return f"{this}{expressions}" if expressions.strip() != "" else this
711
712    def ifblock_sql(self, expression: exp.IfBlock) -> str:
713        this = self.sql(expression, "this")
714        true = self.sql(expression, "true")
715        true = f" {true}" if true else " "
716        false = self.sql(expression, "false")
717        false = f"; ELSE BEGIN {false}" if false else ""
718        return f"IF {this} BEGIN{true}{false}"
719
720    def whileblock_sql(self, expression: exp.WhileBlock) -> str:
721        this = self.sql(expression, "this")
722        body = self.sql(expression, "body")
723        body = f" {body}" if body else " "
724        return f"WHILE {this} BEGIN{body}"
725
726    def execute_sql(self, expression: exp.Execute) -> str:
727        this = self.sql(expression, "this")
728        expressions = self.expressions(expression)
729        expressions = f" {expressions}" if expressions else ""
730        return_status = self.sql(expression, "return_status")
731        return_status = f"{return_status} = " if return_status else ""
732        return f"EXECUTE {return_status}{this}{expressions}"
733
734    def executesql_sql(self, expression: exp.ExecuteSql) -> str:
735        return self.execute_sql(expression)