Merging upstream version 11.7.1.

Signed-off-by: Daniel Baumann <daniel@debian.org>

sqlglot/parser.py

@@ -18,8 +18,13 @@ from sqlglot.trie import in_trie, new_trie
 
 logger = logging.getLogger("sqlglot")
 
+E = t.TypeVar("E", bound=exp.Expression)
+
 
 def parse_var_map(args: t.Sequence) -> exp.Expression:
+    if len(args) == 1 and args[0].is_star:
+        return exp.StarMap(this=args[0])
+
     keys = []
     values = []
     for i in range(0, len(args), 2):
@@ -108,6 +113,8 @@ class Parser(metaclass=_Parser):
         TokenType.CURRENT_USER: exp.CurrentUser,
     }
 
+    JOIN_HINTS: t.Set[str] = set()
+
     NESTED_TYPE_TOKENS = {
         TokenType.ARRAY,
         TokenType.MAP,
@@ -145,6 +152,7 @@ class Parser(metaclass=_Parser):
         TokenType.DATETIME,
         TokenType.DATE,
         TokenType.DECIMAL,
+        TokenType.BIGDECIMAL,
         TokenType.UUID,
         TokenType.GEOGRAPHY,
         TokenType.GEOMETRY,
@@ -221,8 +229,10 @@ class Parser(metaclass=_Parser):
         TokenType.FORMAT,
         TokenType.FULL,
         TokenType.IF,
+        TokenType.IS,
         TokenType.ISNULL,
         TokenType.INTERVAL,
+        TokenType.KEEP,
         TokenType.LAZY,
         TokenType.LEADING,
         TokenType.LEFT,
@@ -235,6 +245,7 @@ class Parser(metaclass=_Parser):
         TokenType.ONLY,
         TokenType.OPTIONS,
         TokenType.ORDINALITY,
+        TokenType.OVERWRITE,
         TokenType.PARTITION,
         TokenType.PERCENT,
         TokenType.PIVOT,
@@ -266,6 +277,8 @@ class Parser(metaclass=_Parser):
         *NO_PAREN_FUNCTIONS,
     }
 
+    INTERVAL_VARS = ID_VAR_TOKENS - {TokenType.END}
+
     TABLE_ALIAS_TOKENS = ID_VAR_TOKENS - {
         TokenType.APPLY,
         TokenType.FULL,
@@ -276,6 +289,8 @@ class Parser(metaclass=_Parser):
         TokenType.WINDOW,
     }
 
+    COMMENT_TABLE_ALIAS_TOKENS = TABLE_ALIAS_TOKENS - {TokenType.IS}
+
     UPDATE_ALIAS_TOKENS = TABLE_ALIAS_TOKENS - {TokenType.SET}
 
     TRIM_TYPES = {TokenType.LEADING, TokenType.TRAILING, TokenType.BOTH}
@@ -400,7 +415,7 @@ class Parser(metaclass=_Parser):
     COLUMN_OPERATORS = {
         TokenType.DOT: None,
         TokenType.DCOLON: lambda self, this, to: self.expression(
-            exp.Cast,
+            exp.Cast if self.STRICT_CAST else exp.TryCast,
             this=this,
             to=to,
         ),
@@ -560,7 +575,7 @@ class Parser(metaclass=_Parser):
         ),
         "DEFINER": lambda self: self._parse_definer(),
         "DETERMINISTIC": lambda self: self.expression(
-            exp.VolatilityProperty, this=exp.Literal.string("IMMUTABLE")
+            exp.StabilityProperty, this=exp.Literal.string("IMMUTABLE")
         ),
         "DISTKEY": lambda self: self._parse_distkey(),
         "DISTSTYLE": lambda self: self._parse_property_assignment(exp.DistStyleProperty),
@@ -571,7 +586,7 @@ class Parser(metaclass=_Parser):
         "FREESPACE": lambda self: self._parse_freespace(),
         "GLOBAL": lambda self: self._parse_temporary(global_=True),
         "IMMUTABLE": lambda self: self.expression(
-            exp.VolatilityProperty, this=exp.Literal.string("IMMUTABLE")
+            exp.StabilityProperty, this=exp.Literal.string("IMMUTABLE")
         ),
         "JOURNAL": lambda self: self._parse_journal(
             no=self._prev.text.upper() == "NO", dual=self._prev.text.upper() == "DUAL"
@@ -600,20 +615,20 @@ class Parser(metaclass=_Parser):
         "PARTITIONED_BY": lambda self: self._parse_partitioned_by(),
         "RETURNS": lambda self: self._parse_returns(),
         "ROW": lambda self: self._parse_row(),
+        "ROW_FORMAT": lambda self: self._parse_property_assignment(exp.RowFormatProperty),
         "SET": lambda self: self.expression(exp.SetProperty, multi=False),
         "SORTKEY": lambda self: self._parse_sortkey(),
         "STABLE": lambda self: self.expression(
-            exp.VolatilityProperty, this=exp.Literal.string("STABLE")
+            exp.StabilityProperty, this=exp.Literal.string("STABLE")
         ),
-        "STORED": lambda self: self._parse_property_assignment(exp.FileFormatProperty),
+        "STORED": lambda self: self._parse_stored(),
         "TABLE_FORMAT": lambda self: self._parse_property_assignment(exp.TableFormatProperty),
         "TBLPROPERTIES": lambda self: self._parse_wrapped_csv(self._parse_property),
+        "TEMP": lambda self: self._parse_temporary(global_=False),
         "TEMPORARY": lambda self: self._parse_temporary(global_=False),
         "TRANSIENT": lambda self: self.expression(exp.TransientProperty),
         "USING": lambda self: self._parse_property_assignment(exp.TableFormatProperty),
-        "VOLATILE": lambda self: self.expression(
-            exp.VolatilityProperty, this=exp.Literal.string("VOLATILE")
-        ),
+        "VOLATILE": lambda self: self._parse_volatile_property(),
         "WITH": lambda self: self._parse_with_property(),
     }
 
@@ -648,8 +663,11 @@ class Parser(metaclass=_Parser):
         "LIKE": lambda self: self._parse_create_like(),
         "NOT": lambda self: self._parse_not_constraint(),
         "NULL": lambda self: self.expression(exp.NotNullColumnConstraint, allow_null=True),
+        "ON": lambda self: self._match(TokenType.UPDATE)
+        and self.expression(exp.OnUpdateColumnConstraint, this=self._parse_function()),
         "PATH": lambda self: self.expression(exp.PathColumnConstraint, this=self._parse_string()),
         "PRIMARY KEY": lambda self: self._parse_primary_key(),
+        "REFERENCES": lambda self: self._parse_references(match=False),
         "TITLE": lambda self: self.expression(
             exp.TitleColumnConstraint, this=self._parse_var_or_string()
         ),
@@ -668,9 +686,14 @@ class Parser(metaclass=_Parser):
     SCHEMA_UNNAMED_CONSTRAINTS = {"CHECK", "FOREIGN KEY", "LIKE", "PRIMARY KEY", "UNIQUE"}
 
     NO_PAREN_FUNCTION_PARSERS = {
+        TokenType.ANY: lambda self: self.expression(exp.Any, this=self._parse_bitwise()),
         TokenType.CASE: lambda self: self._parse_case(),
         TokenType.IF: lambda self: self._parse_if(),
-        TokenType.ANY: lambda self: self.expression(exp.Any, this=self._parse_bitwise()),
+        TokenType.NEXT_VALUE_FOR: lambda self: self.expression(
+            exp.NextValueFor,
+            this=self._parse_column(),
+            order=self._match(TokenType.OVER) and self._parse_wrapped(self._parse_order),
+        ),
     }
 
     FUNCTION_PARSERS: t.Dict[str, t.Callable] = {
@@ -715,6 +738,8 @@ class Parser(metaclass=_Parser):
 
     SHOW_PARSERS: t.Dict[str, t.Callable] = {}
 
+    TYPE_LITERAL_PARSERS: t.Dict[exp.DataType.Type, t.Callable] = {}
+
     MODIFIABLES = (exp.Subquery, exp.Subqueryable, exp.Table)
 
     TRANSACTION_KIND = {"DEFERRED", "IMMEDIATE", "EXCLUSIVE"}
@@ -731,6 +756,7 @@ class Parser(metaclass=_Parser):
     INSERT_ALTERNATIVES = {"ABORT", "FAIL", "IGNORE", "REPLACE", "ROLLBACK"}
 
     WINDOW_ALIAS_TOKENS = ID_VAR_TOKENS - {TokenType.ROWS}
+    WINDOW_BEFORE_PAREN_TOKENS = {TokenType.OVER}
 
     ADD_CONSTRAINT_TOKENS = {TokenType.CONSTRAINT, TokenType.PRIMARY_KEY, TokenType.FOREIGN_KEY}
 
@@ -738,6 +764,9 @@ class Parser(metaclass=_Parser):
 
     CONVERT_TYPE_FIRST = False
 
+    QUOTED_PIVOT_COLUMNS: t.Optional[bool] = None
+    PREFIXED_PIVOT_COLUMNS = False
+
     LOG_BASE_FIRST = True
     LOG_DEFAULTS_TO_LN = False
 
@@ -895,8 +924,8 @@ class Parser(metaclass=_Parser):
         error level setting.
         """
         token = token or self._curr or self._prev or Token.string("")
-        start = self._find_token(token)
-        end = start + len(token.text)
+        start = token.start
+        end = token.end
         start_context = self.sql[max(start - self.error_message_context, 0) : start]
         highlight = self.sql[start:end]
         end_context = self.sql[end : end + self.error_message_context]
@@ -918,8 +947,8 @@ class Parser(metaclass=_Parser):
         self.errors.append(error)
 
     def expression(
-        self, exp_class: t.Type[exp.Expression], comments: t.Optional[t.List[str]] = None, **kwargs
-    ) -> exp.Expression:
+        self, exp_class: t.Type[E], comments: t.Optional[t.List[str]] = None, **kwargs
+    ) -> E:
         """
         Creates a new, validated Expression.
 
@@ -958,22 +987,7 @@ class Parser(metaclass=_Parser):
             self.raise_error(error_message)
 
     def _find_sql(self, start: Token, end: Token) -> str:
-        return self.sql[self._find_token(start) : self._find_token(end) + len(end.text)]
-
-    def _find_token(self, token: Token) -> int:
-        line = 1
-        col = 1
-        index = 0
-
-        while line < token.line or col < token.col:
-            if Tokenizer.WHITE_SPACE.get(self.sql[index]) == TokenType.BREAK:
-                line += 1
-                col = 1
-            else:
-                col += 1
-            index += 1
-
-        return index
+        return self.sql[start.start : end.end]
 
     def _advance(self, times: int = 1) -> None:
         self._index += times
@@ -990,7 +1004,7 @@ class Parser(metaclass=_Parser):
         if index != self._index:
             self._advance(index - self._index)
 
-    def _parse_command(self) -> exp.Expression:
+    def _parse_command(self) -> exp.Command:
         return self.expression(exp.Command, this=self._prev.text, expression=self._parse_string())
 
     def _parse_comment(self, allow_exists: bool = True) -> exp.Expression:
@@ -1007,7 +1021,7 @@ class Parser(metaclass=_Parser):
         if kind.token_type in (TokenType.FUNCTION, TokenType.PROCEDURE):
             this = self._parse_user_defined_function(kind=kind.token_type)
         elif kind.token_type == TokenType.TABLE:
-            this = self._parse_table()
+            this = self._parse_table(alias_tokens=self.COMMENT_TABLE_ALIAS_TOKENS)
         elif kind.token_type == TokenType.COLUMN:
             this = self._parse_column()
         else:
@@ -1035,16 +1049,13 @@ class Parser(metaclass=_Parser):
         self._parse_query_modifiers(expression)
         return expression
 
-    def _parse_drop(self, default_kind: t.Optional[str] = None) -> t.Optional[exp.Expression]:
+    def _parse_drop(self) -> t.Optional[exp.Drop | exp.Command]:
         start = self._prev
         temporary = self._match(TokenType.TEMPORARY)
         materialized = self._match(TokenType.MATERIALIZED)
         kind = self._match_set(self.CREATABLES) and self._prev.text
         if not kind:
-            if default_kind:
-                kind = default_kind
-            else:
-                return self._parse_as_command(start)
+            return self._parse_as_command(start)
 
         return self.expression(
             exp.Drop,
@@ -1055,6 +1066,7 @@ class Parser(metaclass=_Parser):
             materialized=materialized,
             cascade=self._match(TokenType.CASCADE),
             constraints=self._match_text_seq("CONSTRAINTS"),
+            purge=self._match_text_seq("PURGE"),
         )
 
     def _parse_exists(self, not_: bool = False) -> t.Optional[bool]:
@@ -1070,7 +1082,6 @@ class Parser(metaclass=_Parser):
             TokenType.OR, TokenType.REPLACE
         )
         unique = self._match(TokenType.UNIQUE)
-        volatile = self._match(TokenType.VOLATILE)
 
         if self._match_pair(TokenType.TABLE, TokenType.FUNCTION, advance=False):
             self._match(TokenType.TABLE)
@@ -1179,7 +1190,6 @@ class Parser(metaclass=_Parser):
             kind=create_token.text,
             replace=replace,
             unique=unique,
-            volatile=volatile,
             expression=expression,
             exists=exists,
             properties=properties,
@@ -1225,6 +1235,21 @@ class Parser(metaclass=_Parser):
 
         return None
 
+    def _parse_stored(self) -> exp.Expression:
+        self._match(TokenType.ALIAS)
+
+        input_format = self._parse_string() if self._match_text_seq("INPUTFORMAT") else None
+        output_format = self._parse_string() if self._match_text_seq("OUTPUTFORMAT") else None
+
+        return self.expression(
+            exp.FileFormatProperty,
+            this=self.expression(
+                exp.InputOutputFormat, input_format=input_format, output_format=output_format
+            )
+            if input_format or output_format
+            else self._parse_var_or_string() or self._parse_number() or self._parse_id_var(),
+        )
+
     def _parse_property_assignment(self, exp_class: t.Type[exp.Expression]) -> exp.Expression:
         self._match(TokenType.EQ)
         self._match(TokenType.ALIAS)
@@ -1258,6 +1283,21 @@ class Parser(metaclass=_Parser):
             exp.FallbackProperty, no=no, protection=self._match_text_seq("PROTECTION")
         )
 
+    def _parse_volatile_property(self) -> exp.Expression:
+        if self._index >= 2:
+            pre_volatile_token = self._tokens[self._index - 2]
+        else:
+            pre_volatile_token = None
+
+        if pre_volatile_token and pre_volatile_token.token_type in (
+            TokenType.CREATE,
+            TokenType.REPLACE,
+            TokenType.UNIQUE,
+        ):
+            return exp.VolatileProperty()
+
+        return self.expression(exp.StabilityProperty, this=exp.Literal.string("VOLATILE"))
+
     def _parse_with_property(
         self,
     ) -> t.Union[t.Optional[exp.Expression], t.List[t.Optional[exp.Expression]]]:
@@ -1574,11 +1614,46 @@ class Parser(metaclass=_Parser):
             exists=self._parse_exists(),
             partition=self._parse_partition(),
             expression=self._parse_ddl_select(),
+            conflict=self._parse_on_conflict(),
             returning=self._parse_returning(),
             overwrite=overwrite,
             alternative=alternative,
         )
 
+    def _parse_on_conflict(self) -> t.Optional[exp.Expression]:
+        conflict = self._match_text_seq("ON", "CONFLICT")
+        duplicate = self._match_text_seq("ON", "DUPLICATE", "KEY")
+
+        if not (conflict or duplicate):
+            return None
+
+        nothing = None
+        expressions = None
+        key = None
+        constraint = None
+
+        if conflict:
+            if self._match_text_seq("ON", "CONSTRAINT"):
+                constraint = self._parse_id_var()
+            else:
+                key = self._parse_csv(self._parse_value)
+
+        self._match_text_seq("DO")
+        if self._match_text_seq("NOTHING"):
+            nothing = True
+        else:
+            self._match(TokenType.UPDATE)
+            expressions = self._match(TokenType.SET) and self._parse_csv(self._parse_equality)
+
+        return self.expression(
+            exp.OnConflict,
+            duplicate=duplicate,
+            expressions=expressions,
+            nothing=nothing,
+            key=key,
+            constraint=constraint,
+        )
+
     def _parse_returning(self) -> t.Optional[exp.Expression]:
         if not self._match(TokenType.RETURNING):
             return None
@@ -1639,7 +1714,7 @@ class Parser(metaclass=_Parser):
 
         return self.expression(
             exp.Delete,
-            this=self._parse_table(schema=True),
+            this=self._parse_table(),
             using=self._parse_csv(lambda: self._match(TokenType.USING) and self._parse_table()),
             where=self._parse_where(),
             returning=self._parse_returning(),
@@ -1792,6 +1867,7 @@ class Parser(metaclass=_Parser):
         if not skip_with_token and not self._match(TokenType.WITH):
             return None
 
+        comments = self._prev_comments
         recursive = self._match(TokenType.RECURSIVE)
 
         expressions = []
@@ -1803,7 +1879,9 @@ class Parser(metaclass=_Parser):
             else:
                 self._match(TokenType.WITH)
 
-        return self.expression(exp.With, expressions=expressions, recursive=recursive)
+        return self.expression(
+            exp.With, comments=comments, expressions=expressions, recursive=recursive
+        )
 
     def _parse_cte(self) -> exp.Expression:
         alias = self._parse_table_alias()
@@ -1856,15 +1934,20 @@ class Parser(metaclass=_Parser):
         table = isinstance(this, exp.Table)
 
         while True:
-            lateral = self._parse_lateral()
             join = self._parse_join()
-            comma = None if table else self._match(TokenType.COMMA)
-            if lateral:
-                this.append("laterals", lateral)
             if join:
                 this.append("joins", join)
+
+            lateral = None
+            if not join:
+                lateral = self._parse_lateral()
+                if lateral:
+                    this.append("laterals", lateral)
+
+            comma = None if table else self._match(TokenType.COMMA)
             if comma:
                 this.args["from"].append("expressions", self._parse_table())
+
             if not (lateral or join or comma):
                 break
 
@@ -1906,14 +1989,13 @@ class Parser(metaclass=_Parser):
     def _parse_match_recognize(self) -> t.Optional[exp.Expression]:
         if not self._match(TokenType.MATCH_RECOGNIZE):
             return None
+
         self._match_l_paren()
 
         partition = self._parse_partition_by()
         order = self._parse_order()
         measures = (
-            self._parse_alias(self._parse_conjunction())
-            if self._match_text_seq("MEASURES")
-            else None
+            self._parse_csv(self._parse_expression) if self._match_text_seq("MEASURES") else None
         )
 
         if self._match_text_seq("ONE", "ROW", "PER", "MATCH"):
@@ -1967,8 +2049,17 @@ class Parser(metaclass=_Parser):
             pattern = None
 
         define = (
-            self._parse_alias(self._parse_conjunction()) if self._match_text_seq("DEFINE") else None
+            self._parse_csv(
+                lambda: self.expression(
+                    exp.Alias,
+                    alias=self._parse_id_var(any_token=True),
+                    this=self._match(TokenType.ALIAS) and self._parse_conjunction(),
+                )
+            )
+            if self._match_text_seq("DEFINE")
+            else None
         )
+
         self._match_r_paren()
 
         return self.expression(
@@ -1980,6 +2071,7 @@ class Parser(metaclass=_Parser):
             after=after,
             pattern=pattern,
             define=define,
+            alias=self._parse_table_alias(),
         )
 
     def _parse_lateral(self) -> t.Optional[exp.Expression]:
@@ -2022,9 +2114,6 @@ class Parser(metaclass=_Parser):
             alias=table_alias,
         )
 
-        if outer_apply or cross_apply:
-            return self.expression(exp.Join, this=expression, side=None if cross_apply else "LEFT")
-
         return expression
 
     def _parse_join_side_and_kind(
@@ -2037,11 +2126,26 @@ class Parser(metaclass=_Parser):
         )
 
     def _parse_join(self, skip_join_token: bool = False) -> t.Optional[exp.Expression]:
+        index = self._index
         natural, side, kind = self._parse_join_side_and_kind()
+        hint = self._prev.text if self._match_texts(self.JOIN_HINTS) else None
+        join = self._match(TokenType.JOIN)
 
-        if not skip_join_token and not self._match(TokenType.JOIN):
+        if not skip_join_token and not join:
+            self._retreat(index)
+            kind = None
+            natural = None
+            side = None
+
+        outer_apply = self._match_pair(TokenType.OUTER, TokenType.APPLY, False)
+        cross_apply = self._match_pair(TokenType.CROSS, TokenType.APPLY, False)
+
+        if not skip_join_token and not join and not outer_apply and not cross_apply:
             return None
 
+        if outer_apply:
+            side = Token(TokenType.LEFT, "LEFT")
+
         kwargs: t.Dict[
             str, t.Optional[exp.Expression] | bool | str | t.List[t.Optional[exp.Expression]]
         ] = {"this": self._parse_table()}
@@ -2052,6 +2156,8 @@ class Parser(metaclass=_Parser):
             kwargs["side"] = side.text
         if kind:
             kwargs["kind"] = kind.text
+        if hint:
+            kwargs["hint"] = hint
 
         if self._match(TokenType.ON):
             kwargs["on"] = self._parse_conjunction()
@@ -2179,7 +2285,7 @@ class Parser(metaclass=_Parser):
             return None
 
         expressions = self._parse_wrapped_csv(self._parse_column)
-        ordinality = bool(self._match(TokenType.WITH) and self._match(TokenType.ORDINALITY))
+        ordinality = self._match_pair(TokenType.WITH, TokenType.ORDINALITY)
         alias = self._parse_table_alias()
 
         if alias and self.unnest_column_only:
@@ -2191,7 +2297,7 @@ class Parser(metaclass=_Parser):
         offset = None
         if self._match_pair(TokenType.WITH, TokenType.OFFSET):
             self._match(TokenType.ALIAS)
-            offset = self._parse_conjunction()
+            offset = self._parse_id_var() or exp.Identifier(this="offset")
 
         return self.expression(
             exp.Unnest,
@@ -2294,6 +2400,9 @@ class Parser(metaclass=_Parser):
         else:
             expressions = self._parse_csv(lambda: self._parse_alias(self._parse_function()))
 
+        if not expressions:
+            self.raise_error("Failed to parse PIVOT's aggregation list")
+
         if not self._match(TokenType.FOR):
             self.raise_error("Expecting FOR")
 
@@ -2311,8 +2420,26 @@ class Parser(metaclass=_Parser):
         if not self._match_set((TokenType.PIVOT, TokenType.UNPIVOT), advance=False):
             pivot.set("alias", self._parse_table_alias())
 
+        if not unpivot:
+            names = self._pivot_column_names(t.cast(t.List[exp.Expression], expressions))
+
+            columns: t.List[exp.Expression] = []
+            for col in pivot.args["field"].expressions:
+                for name in names:
+                    if self.PREFIXED_PIVOT_COLUMNS:
+                        name = f"{name}_{col.alias_or_name}" if name else col.alias_or_name
+                    else:
+                        name = f"{col.alias_or_name}_{name}" if name else col.alias_or_name
+
+                    columns.append(exp.to_identifier(name, quoted=self.QUOTED_PIVOT_COLUMNS))
+
+            pivot.set("columns", columns)
+
         return pivot
 
+    def _pivot_column_names(self, pivot_columns: t.List[exp.Expression]) -> t.List[str]:
+        return [agg.alias for agg in pivot_columns]
+
     def _parse_where(self, skip_where_token: bool = False) -> t.Optional[exp.Expression]:
         if not skip_where_token and not self._match(TokenType.WHERE):
             return None
@@ -2433,10 +2560,25 @@ class Parser(metaclass=_Parser):
         if self._match(TokenType.FETCH):
             direction = self._match_set((TokenType.FIRST, TokenType.NEXT))
             direction = self._prev.text if direction else "FIRST"
+
             count = self._parse_number()
+            percent = self._match(TokenType.PERCENT)
+
             self._match_set((TokenType.ROW, TokenType.ROWS))
-            self._match(TokenType.ONLY)
-            return self.expression(exp.Fetch, direction=direction, count=count)
+
+            only = self._match(TokenType.ONLY)
+            with_ties = self._match_text_seq("WITH", "TIES")
+
+            if only and with_ties:
+                self.raise_error("Cannot specify both ONLY and WITH TIES in FETCH clause")
+
+            return self.expression(
+                exp.Fetch,
+                direction=direction,
+                count=count,
+                percent=percent,
+                with_ties=with_ties,
+            )
 
         return this
 
@@ -2493,7 +2635,11 @@ class Parser(metaclass=_Parser):
         negate = self._match(TokenType.NOT)
 
         if self._match_set(self.RANGE_PARSERS):
-            this = self.RANGE_PARSERS[self._prev.token_type](self, this)
+            expression = self.RANGE_PARSERS[self._prev.token_type](self, this)
+            if not expression:
+                return this
+
+            this = expression
         elif self._match(TokenType.ISNULL):
             this = self.expression(exp.Is, this=this, expression=exp.Null())
 
@@ -2511,17 +2657,19 @@ class Parser(metaclass=_Parser):
 
         return this
 
-    def _parse_is(self, this: t.Optional[exp.Expression]) -> exp.Expression:
+    def _parse_is(self, this: t.Optional[exp.Expression]) -> t.Optional[exp.Expression]:
+        index = self._index - 1
         negate = self._match(TokenType.NOT)
         if self._match(TokenType.DISTINCT_FROM):
             klass = exp.NullSafeEQ if negate else exp.NullSafeNEQ
             return self.expression(klass, this=this, expression=self._parse_expression())
 
-        this = self.expression(
-            exp.Is,
-            this=this,
-            expression=self._parse_null() or self._parse_boolean(),
-        )
+        expression = self._parse_null() or self._parse_boolean()
+        if not expression:
+            self._retreat(index)
+            return None
+
+        this = self.expression(exp.Is, this=this, expression=expression)
         return self.expression(exp.Not, this=this) if negate else this
 
     def _parse_in(self, this: t.Optional[exp.Expression]) -> exp.Expression:
@@ -2553,6 +2701,27 @@ class Parser(metaclass=_Parser):
             return this
         return self.expression(exp.Escape, this=this, expression=self._parse_string())
 
+    def _parse_interval(self) -> t.Optional[exp.Expression]:
+        if not self._match(TokenType.INTERVAL):
+            return None
+
+        this = self._parse_primary() or self._parse_term()
+        unit = self._parse_function() or self._parse_var()
+
+        # Most dialects support, e.g., the form INTERVAL '5' day, thus we try to parse
+        # each INTERVAL expression into this canonical form so it's easy to transpile
+        if this and isinstance(this, exp.Literal):
+            if this.is_number:
+                this = exp.Literal.string(this.name)
+
+            # Try to not clutter Snowflake's multi-part intervals like INTERVAL '1 day, 1 year'
+            parts = this.name.split()
+            if not unit and len(parts) <= 2:
+                this = exp.Literal.string(seq_get(parts, 0))
+                unit = self.expression(exp.Var, this=seq_get(parts, 1))
+
+        return self.expression(exp.Interval, this=this, unit=unit)
+
     def _parse_bitwise(self) -> t.Optional[exp.Expression]:
         this = self._parse_term()
 
@@ -2588,20 +2757,24 @@ class Parser(metaclass=_Parser):
         return self._parse_at_time_zone(self._parse_type())
 
     def _parse_type(self) -> t.Optional[exp.Expression]:
-        if self._match(TokenType.INTERVAL):
-            return self.expression(exp.Interval, this=self._parse_term(), unit=self._parse_field())
+        interval = self._parse_interval()
+        if interval:
+            return interval
 
         index = self._index
-        type_token = self._parse_types(check_func=True)
+        data_type = self._parse_types(check_func=True)
         this = self._parse_column()
 
-        if type_token:
+        if data_type:
             if isinstance(this, exp.Literal):
-                return self.expression(exp.Cast, this=this, to=type_token)
-            if not type_token.args.get("expressions"):
+                parser = self.TYPE_LITERAL_PARSERS.get(data_type.this)
+                if parser:
+                    return parser(self, this, data_type)
+                return self.expression(exp.Cast, this=this, to=data_type)
+            if not data_type.args.get("expressions"):
                 self._retreat(index)
                 return self._parse_column()
-            return type_token
+            return data_type
 
         return this
 
@@ -2631,11 +2804,10 @@ class Parser(metaclass=_Parser):
             else:
                 expressions = self._parse_csv(self._parse_conjunction)
 
-            if not expressions:
+            if not expressions or not self._match(TokenType.R_PAREN):
                 self._retreat(index)
                 return None
 
-            self._match_r_paren()
             maybe_func = True
 
         if self._match_pair(TokenType.L_BRACKET, TokenType.R_BRACKET):
@@ -2720,15 +2892,14 @@ class Parser(metaclass=_Parser):
         )
 
     def _parse_struct_kwargs(self) -> t.Optional[exp.Expression]:
-        if self._curr and self._curr.token_type in self.TYPE_TOKENS:
-            return self._parse_types()
-
+        index = self._index
         this = self._parse_id_var()
         self._match(TokenType.COLON)
         data_type = self._parse_types()
 
         if not data_type:
-            return None
+            self._retreat(index)
+            return self._parse_types()
         return self.expression(exp.StructKwarg, this=this, expression=data_type)
 
     def _parse_at_time_zone(self, this: t.Optional[exp.Expression]) -> t.Optional[exp.Expression]:
@@ -2825,6 +2996,7 @@ class Parser(metaclass=_Parser):
                 this = self.expression(exp.Paren, this=self._parse_set_operations(this))
 
             self._match_r_paren()
+            comments.extend(self._prev_comments)
 
             if this and comments:
                 this.comments = comments
@@ -2833,8 +3005,16 @@ class Parser(metaclass=_Parser):
 
         return None
 
-    def _parse_field(self, any_token: bool = False) -> t.Optional[exp.Expression]:
-        return self._parse_primary() or self._parse_function() or self._parse_id_var(any_token)
+    def _parse_field(
+        self,
+        any_token: bool = False,
+        tokens: t.Optional[t.Collection[TokenType]] = None,
+    ) -> t.Optional[exp.Expression]:
+        return (
+            self._parse_primary()
+            or self._parse_function()
+            or self._parse_id_var(any_token=any_token, tokens=tokens)
+        )
 
     def _parse_function(
         self, functions: t.Optional[t.Dict[str, t.Callable]] = None
@@ -3079,12 +3259,10 @@ class Parser(metaclass=_Parser):
         return None
 
     def _parse_column_constraint(self) -> t.Optional[exp.Expression]:
-        this = self._parse_references()
-        if this:
-            return this
-
         if self._match(TokenType.CONSTRAINT):
             this = self._parse_id_var()
+        else:
+            this = None
 
         if self._match_texts(self.CONSTRAINT_PARSERS):
             return self.expression(
@@ -3164,8 +3342,8 @@ class Parser(metaclass=_Parser):
 
         return options
 
-    def _parse_references(self) -> t.Optional[exp.Expression]:
-        if not self._match(TokenType.REFERENCES):
+    def _parse_references(self, match=True) -> t.Optional[exp.Expression]:
+        if match and not self._match(TokenType.REFERENCES):
             return None
 
         expressions = None
@@ -3234,7 +3412,7 @@ class Parser(metaclass=_Parser):
         elif not this or this.name.upper() == "ARRAY":
             this = self.expression(exp.Array, expressions=expressions)
         else:
-            expressions = apply_index_offset(expressions, -self.index_offset)
+            expressions = apply_index_offset(this, expressions, -self.index_offset)
             this = self.expression(exp.Bracket, this=this, expressions=expressions)
 
         if not self._match(TokenType.R_BRACKET) and bracket_kind == TokenType.L_BRACKET:
@@ -3279,7 +3457,13 @@ class Parser(metaclass=_Parser):
             self.validate_expression(this, args)
             self._match_r_paren()
         else:
+            index = self._index - 1
             condition = self._parse_conjunction()
+
+            if not condition:
+                self._retreat(index)
+                return None
+
             self._match(TokenType.THEN)
             true = self._parse_conjunction()
             false = self._parse_conjunction() if self._match(TokenType.ELSE) else None
@@ -3591,14 +3775,24 @@ class Parser(metaclass=_Parser):
 
         # bigquery select from window x AS (partition by ...)
         if alias:
+            over = None
             self._match(TokenType.ALIAS)
-        elif not self._match(TokenType.OVER):
+        elif not self._match_set(self.WINDOW_BEFORE_PAREN_TOKENS):
             return this
+        else:
+            over = self._prev.text.upper()
 
         if not self._match(TokenType.L_PAREN):
-            return self.expression(exp.Window, this=this, alias=self._parse_id_var(False))
+            return self.expression(
+                exp.Window, this=this, alias=self._parse_id_var(False), over=over
+            )
 
         window_alias = self._parse_id_var(any_token=False, tokens=self.WINDOW_ALIAS_TOKENS)
+
+        first = self._match(TokenType.FIRST)
+        if self._match_text_seq("LAST"):
+            first = False
+
         partition = self._parse_partition_by()
         order = self._parse_order()
         kind = self._match_set((TokenType.ROWS, TokenType.RANGE)) and self._prev.text
@@ -3629,6 +3823,8 @@ class Parser(metaclass=_Parser):
             order=order,
             spec=spec,
             alias=window_alias,
+            over=over,
+            first=first,
         )
 
     def _parse_window_spec(self) -> t.Dict[str, t.Optional[str | exp.Expression]]:
@@ -3886,7 +4082,10 @@ class Parser(metaclass=_Parser):
         return expression
 
     def _parse_drop_column(self) -> t.Optional[exp.Expression]:
-        return self._match(TokenType.DROP) and self._parse_drop(default_kind="COLUMN")
+        drop = self._match(TokenType.DROP) and self._parse_drop()
+        if drop and not isinstance(drop, exp.Command):
+            drop.set("kind", drop.args.get("kind", "COLUMN"))
+        return drop
 
     # https://docs.aws.amazon.com/athena/latest/ug/alter-table-drop-partition.html
     def _parse_drop_partition(self, exists: t.Optional[bool] = None) -> exp.Expression:
@@ -4010,7 +4209,7 @@ class Parser(metaclass=_Parser):
             if self._match(TokenType.INSERT):
                 _this = self._parse_star()
                 if _this:
-                    then = self.expression(exp.Insert, this=_this)
+                    then: t.Optional[exp.Expression] = self.expression(exp.Insert, this=_this)
                 else:
                     then = self.expression(
                         exp.Insert,
@@ -4239,5 +4438,8 @@ class Parser(metaclass=_Parser):
                         break
                     parent = parent.parent
                 else:
-                    column.replace(dot_or_id)
+                    if column is node:
+                        node = dot_or_id
+                    else:
+                        column.replace(dot_or_id)
         return node