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sqlglot.dialects.clickhouse

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  1from __future__ import annotations
  2
  3import typing as t
  4
  5from sqlglot import exp, generator, parser, tokens
  6from sqlglot.dialects.dialect import Dialect, inline_array_sql, var_map_sql
  7from sqlglot.errors import ParseError
  8from sqlglot.parser import parse_var_map
  9from sqlglot.tokens import TokenType
 10
 11
 12def _lower_func(sql: str) -> str:
 13    index = sql.index("(")
 14    return sql[:index].lower() + sql[index:]
 15
 16
 17class ClickHouse(Dialect):
 18    normalize_functions = None
 19    null_ordering = "nulls_are_last"
 20
 21    class Tokenizer(tokens.Tokenizer):
 22        COMMENTS = ["--", "#", "#!", ("/*", "*/")]
 23        IDENTIFIERS = ['"', "`"]
 24
 25        KEYWORDS = {
 26            **tokens.Tokenizer.KEYWORDS,
 27            "ASOF": TokenType.ASOF,
 28            "GLOBAL": TokenType.GLOBAL,
 29            "DATETIME64": TokenType.DATETIME,
 30            "FINAL": TokenType.FINAL,
 31            "FLOAT32": TokenType.FLOAT,
 32            "FLOAT64": TokenType.DOUBLE,
 33            "INT16": TokenType.SMALLINT,
 34            "INT32": TokenType.INT,
 35            "INT64": TokenType.BIGINT,
 36            "INT8": TokenType.TINYINT,
 37            "TUPLE": TokenType.STRUCT,
 38        }
 39
 40    class Parser(parser.Parser):
 41        FUNCTIONS = {
 42            **parser.Parser.FUNCTIONS,  # type: ignore
 43            "MAP": parse_var_map,
 44            "QUANTILE": lambda params, args: exp.Quantile(this=args, quantile=params),
 45            "QUANTILES": lambda params, args: exp.Quantiles(parameters=params, expressions=args),
 46            "QUANTILEIF": lambda params, args: exp.QuantileIf(parameters=params, expressions=args),
 47        }
 48
 49        RANGE_PARSERS = {
 50            **parser.Parser.RANGE_PARSERS,
 51            TokenType.GLOBAL: lambda self, this: self._match(TokenType.IN)
 52            and self._parse_in(this, is_global=True),
 53        }
 54
 55        JOIN_KINDS = {*parser.Parser.JOIN_KINDS, TokenType.ANY, TokenType.ASOF}  # type: ignore
 56
 57        TABLE_ALIAS_TOKENS = {*parser.Parser.TABLE_ALIAS_TOKENS} - {TokenType.ANY}  # type: ignore
 58
 59        INTEGER_DIVISION = False
 60
 61        def _parse_in(
 62            self, this: t.Optional[exp.Expression], is_global: bool = False
 63        ) -> exp.Expression:
 64            this = super()._parse_in(this)
 65            this.set("is_global", is_global)
 66            return this
 67
 68        def _parse_table(
 69            self, schema: bool = False, alias_tokens: t.Optional[t.Collection[TokenType]] = None
 70        ) -> t.Optional[exp.Expression]:
 71            this = super()._parse_table(schema=schema, alias_tokens=alias_tokens)
 72
 73            if self._match(TokenType.FINAL):
 74                this = self.expression(exp.Final, this=this)
 75
 76            return this
 77
 78        def _parse_position(self, haystack_first: bool = False) -> exp.Expression:
 79            return super()._parse_position(haystack_first=True)
 80
 81        # https://clickhouse.com/docs/en/sql-reference/statements/select/with/
 82        def _parse_cte(self) -> exp.Expression:
 83            index = self._index
 84            try:
 85                # WITH <identifier> AS <subquery expression>
 86                return super()._parse_cte()
 87            except ParseError:
 88                # WITH <expression> AS <identifier>
 89                self._retreat(index)
 90                statement = self._parse_statement()
 91
 92                if statement and isinstance(statement.this, exp.Alias):
 93                    self.raise_error("Expected CTE to have alias")
 94
 95                return self.expression(exp.CTE, this=statement, alias=statement and statement.this)
 96
 97    class Generator(generator.Generator):
 98        STRUCT_DELIMITER = ("(", ")")
 99        INTEGER_DIVISION = False
100
101        TYPE_MAPPING = {
102            **generator.Generator.TYPE_MAPPING,  # type: ignore
103            exp.DataType.Type.NULLABLE: "Nullable",
104            exp.DataType.Type.DATETIME: "DateTime64",
105            exp.DataType.Type.MAP: "Map",
106            exp.DataType.Type.ARRAY: "Array",
107            exp.DataType.Type.STRUCT: "Tuple",
108            exp.DataType.Type.TINYINT: "Int8",
109            exp.DataType.Type.SMALLINT: "Int16",
110            exp.DataType.Type.INT: "Int32",
111            exp.DataType.Type.BIGINT: "Int64",
112            exp.DataType.Type.FLOAT: "Float32",
113            exp.DataType.Type.DOUBLE: "Float64",
114        }
115
116        TRANSFORMS = {
117            **generator.Generator.TRANSFORMS,  # type: ignore
118            exp.Array: inline_array_sql,
119            exp.StrPosition: lambda self, e: f"position({self.format_args(e.this, e.args.get('substr'), e.args.get('position'))})",
120            exp.Final: lambda self, e: f"{self.sql(e, 'this')} FINAL",
121            exp.Map: lambda self, e: _lower_func(var_map_sql(self, e)),
122            exp.VarMap: lambda self, e: _lower_func(var_map_sql(self, e)),
123            exp.Quantile: lambda self, e: f"quantile{self._param_args_sql(e, 'quantile', 'this')}",
124            exp.Quantiles: lambda self, e: f"quantiles{self._param_args_sql(e, 'parameters', 'expressions')}",
125            exp.QuantileIf: lambda self, e: f"quantileIf{self._param_args_sql(e, 'parameters', 'expressions')}",
126        }
127
128        EXPLICIT_UNION = True
129
130        def _param_args_sql(
131            self, expression: exp.Expression, params_name: str, args_name: str
132        ) -> str:
133            params = self.format_args(self.expressions(expression, params_name))
134            args = self.format_args(self.expressions(expression, args_name))
135            return f"({params})({args})"
136
137        def cte_sql(self, expression: exp.CTE) -> str:
138            if isinstance(expression.this, exp.Alias):
139                return self.sql(expression, "this")
140
141            return super().cte_sql(expression)

class ClickHouse(sqlglot.dialects.dialect.Dialect): View Source

 18class ClickHouse(Dialect):
 19    normalize_functions = None
 20    null_ordering = "nulls_are_last"
 21
 22    class Tokenizer(tokens.Tokenizer):
 23        COMMENTS = ["--", "#", "#!", ("/*", "*/")]
 24        IDENTIFIERS = ['"', "`"]
 25
 26        KEYWORDS = {
 27            **tokens.Tokenizer.KEYWORDS,
 28            "ASOF": TokenType.ASOF,
 29            "GLOBAL": TokenType.GLOBAL,
 30            "DATETIME64": TokenType.DATETIME,
 31            "FINAL": TokenType.FINAL,
 32            "FLOAT32": TokenType.FLOAT,
 33            "FLOAT64": TokenType.DOUBLE,
 34            "INT16": TokenType.SMALLINT,
 35            "INT32": TokenType.INT,
 36            "INT64": TokenType.BIGINT,
 37            "INT8": TokenType.TINYINT,
 38            "TUPLE": TokenType.STRUCT,
 39        }
 40
 41    class Parser(parser.Parser):
 42        FUNCTIONS = {
 43            **parser.Parser.FUNCTIONS,  # type: ignore
 44            "MAP": parse_var_map,
 45            "QUANTILE": lambda params, args: exp.Quantile(this=args, quantile=params),
 46            "QUANTILES": lambda params, args: exp.Quantiles(parameters=params, expressions=args),
 47            "QUANTILEIF": lambda params, args: exp.QuantileIf(parameters=params, expressions=args),
 48        }
 49
 50        RANGE_PARSERS = {
 51            **parser.Parser.RANGE_PARSERS,
 52            TokenType.GLOBAL: lambda self, this: self._match(TokenType.IN)
 53            and self._parse_in(this, is_global=True),
 54        }
 55
 56        JOIN_KINDS = {*parser.Parser.JOIN_KINDS, TokenType.ANY, TokenType.ASOF}  # type: ignore
 57
 58        TABLE_ALIAS_TOKENS = {*parser.Parser.TABLE_ALIAS_TOKENS} - {TokenType.ANY}  # type: ignore
 59
 60        INTEGER_DIVISION = False
 61
 62        def _parse_in(
 63            self, this: t.Optional[exp.Expression], is_global: bool = False
 64        ) -> exp.Expression:
 65            this = super()._parse_in(this)
 66            this.set("is_global", is_global)
 67            return this
 68
 69        def _parse_table(
 70            self, schema: bool = False, alias_tokens: t.Optional[t.Collection[TokenType]] = None
 71        ) -> t.Optional[exp.Expression]:
 72            this = super()._parse_table(schema=schema, alias_tokens=alias_tokens)
 73
 74            if self._match(TokenType.FINAL):
 75                this = self.expression(exp.Final, this=this)
 76
 77            return this
 78
 79        def _parse_position(self, haystack_first: bool = False) -> exp.Expression:
 80            return super()._parse_position(haystack_first=True)
 81
 82        # https://clickhouse.com/docs/en/sql-reference/statements/select/with/
 83        def _parse_cte(self) -> exp.Expression:
 84            index = self._index
 85            try:
 86                # WITH <identifier> AS <subquery expression>
 87                return super()._parse_cte()
 88            except ParseError:
 89                # WITH <expression> AS <identifier>
 90                self._retreat(index)
 91                statement = self._parse_statement()
 92
 93                if statement and isinstance(statement.this, exp.Alias):
 94                    self.raise_error("Expected CTE to have alias")
 95
 96                return self.expression(exp.CTE, this=statement, alias=statement and statement.this)
 97
 98    class Generator(generator.Generator):
 99        STRUCT_DELIMITER = ("(", ")")
100        INTEGER_DIVISION = False
101
102        TYPE_MAPPING = {
103            **generator.Generator.TYPE_MAPPING,  # type: ignore
104            exp.DataType.Type.NULLABLE: "Nullable",
105            exp.DataType.Type.DATETIME: "DateTime64",
106            exp.DataType.Type.MAP: "Map",
107            exp.DataType.Type.ARRAY: "Array",
108            exp.DataType.Type.STRUCT: "Tuple",
109            exp.DataType.Type.TINYINT: "Int8",
110            exp.DataType.Type.SMALLINT: "Int16",
111            exp.DataType.Type.INT: "Int32",
112            exp.DataType.Type.BIGINT: "Int64",
113            exp.DataType.Type.FLOAT: "Float32",
114            exp.DataType.Type.DOUBLE: "Float64",
115        }
116
117        TRANSFORMS = {
118            **generator.Generator.TRANSFORMS,  # type: ignore
119            exp.Array: inline_array_sql,
120            exp.StrPosition: lambda self, e: f"position({self.format_args(e.this, e.args.get('substr'), e.args.get('position'))})",
121            exp.Final: lambda self, e: f"{self.sql(e, 'this')} FINAL",
122            exp.Map: lambda self, e: _lower_func(var_map_sql(self, e)),
123            exp.VarMap: lambda self, e: _lower_func(var_map_sql(self, e)),
124            exp.Quantile: lambda self, e: f"quantile{self._param_args_sql(e, 'quantile', 'this')}",
125            exp.Quantiles: lambda self, e: f"quantiles{self._param_args_sql(e, 'parameters', 'expressions')}",
126            exp.QuantileIf: lambda self, e: f"quantileIf{self._param_args_sql(e, 'parameters', 'expressions')}",
127        }
128
129        EXPLICIT_UNION = True
130
131        def _param_args_sql(
132            self, expression: exp.Expression, params_name: str, args_name: str
133        ) -> str:
134            params = self.format_args(self.expressions(expression, params_name))
135            args = self.format_args(self.expressions(expression, args_name))
136            return f"({params})({args})"
137
138        def cte_sql(self, expression: exp.CTE) -> str:
139            if isinstance(expression.this, exp.Alias):
140                return self.sql(expression, "this")
141
142            return super().cte_sql(expression)

Inherited Members

sqlglot.dialects.dialect.Dialect: get_or_raise; format_time; parse; parse_into; generate; transpile; parser; generator

class ClickHouse.Tokenizer(sqlglot.tokens.Tokenizer): View Source

22    class Tokenizer(tokens.Tokenizer):
23        COMMENTS = ["--", "#", "#!", ("/*", "*/")]
24        IDENTIFIERS = ['"', "`"]
25
26        KEYWORDS = {
27            **tokens.Tokenizer.KEYWORDS,
28            "ASOF": TokenType.ASOF,
29            "GLOBAL": TokenType.GLOBAL,
30            "DATETIME64": TokenType.DATETIME,
31            "FINAL": TokenType.FINAL,
32            "FLOAT32": TokenType.FLOAT,
33            "FLOAT64": TokenType.DOUBLE,
34            "INT16": TokenType.SMALLINT,
35            "INT32": TokenType.INT,
36            "INT64": TokenType.BIGINT,
37            "INT8": TokenType.TINYINT,
38            "TUPLE": TokenType.STRUCT,
39        }

Inherited Members

sqlglot.tokens.Tokenizer: reset; tokenize

class ClickHouse.Parser(sqlglot.parser.Parser): View Source

41    class Parser(parser.Parser):
42        FUNCTIONS = {
43            **parser.Parser.FUNCTIONS,  # type: ignore
44            "MAP": parse_var_map,
45            "QUANTILE": lambda params, args: exp.Quantile(this=args, quantile=params),
46            "QUANTILES": lambda params, args: exp.Quantiles(parameters=params, expressions=args),
47            "QUANTILEIF": lambda params, args: exp.QuantileIf(parameters=params, expressions=args),
48        }
49
50        RANGE_PARSERS = {
51            **parser.Parser.RANGE_PARSERS,
52            TokenType.GLOBAL: lambda self, this: self._match(TokenType.IN)
53            and self._parse_in(this, is_global=True),
54        }
55
56        JOIN_KINDS = {*parser.Parser.JOIN_KINDS, TokenType.ANY, TokenType.ASOF}  # type: ignore
57
58        TABLE_ALIAS_TOKENS = {*parser.Parser.TABLE_ALIAS_TOKENS} - {TokenType.ANY}  # type: ignore
59
60        INTEGER_DIVISION = False
61
62        def _parse_in(
63            self, this: t.Optional[exp.Expression], is_global: bool = False
64        ) -> exp.Expression:
65            this = super()._parse_in(this)
66            this.set("is_global", is_global)
67            return this
68
69        def _parse_table(
70            self, schema: bool = False, alias_tokens: t.Optional[t.Collection[TokenType]] = None
71        ) -> t.Optional[exp.Expression]:
72            this = super()._parse_table(schema=schema, alias_tokens=alias_tokens)
73
74            if self._match(TokenType.FINAL):
75                this = self.expression(exp.Final, this=this)
76
77            return this
78
79        def _parse_position(self, haystack_first: bool = False) -> exp.Expression:
80            return super()._parse_position(haystack_first=True)
81
82        # https://clickhouse.com/docs/en/sql-reference/statements/select/with/
83        def _parse_cte(self) -> exp.Expression:
84            index = self._index
85            try:
86                # WITH <identifier> AS <subquery expression>
87                return super()._parse_cte()
88            except ParseError:
89                # WITH <expression> AS <identifier>
90                self._retreat(index)
91                statement = self._parse_statement()
92
93                if statement and isinstance(statement.this, exp.Alias):
94                    self.raise_error("Expected CTE to have alias")
95
96                return self.expression(exp.CTE, this=statement, alias=statement and statement.this)

Parser consumes a list of tokens produced by the sqlglot.tokens.Tokenizer and produces a parsed syntax tree.

Arguments:

error_level: the desired error level. Default: ErrorLevel.RAISE
error_message_context: determines the amount of context to capture from a query string when displaying the error message (in number of characters). Default: 50.
index_offset: Index offset for arrays eg ARRAY[0] vs ARRAY[1] as the head of a list. Default: 0
alias_post_tablesample: If the table alias comes after tablesample. Default: False
max_errors: Maximum number of error messages to include in a raised ParseError. This is only relevant if error_level is ErrorLevel.RAISE. Default: 3
null_ordering: Indicates the default null ordering method to use if not explicitly set. Options are "nulls_are_small", "nulls_are_large", "nulls_are_last". Default: "nulls_are_small"

Inherited Members

sqlglot.parser.Parser: Parser; reset; parse; parse_into; check_errors; raise_error; expression; validate_expression

class ClickHouse.Generator(sqlglot.generator.Generator): View Source

 98    class Generator(generator.Generator):
 99        STRUCT_DELIMITER = ("(", ")")
100        INTEGER_DIVISION = False
101
102        TYPE_MAPPING = {
103            **generator.Generator.TYPE_MAPPING,  # type: ignore
104            exp.DataType.Type.NULLABLE: "Nullable",
105            exp.DataType.Type.DATETIME: "DateTime64",
106            exp.DataType.Type.MAP: "Map",
107            exp.DataType.Type.ARRAY: "Array",
108            exp.DataType.Type.STRUCT: "Tuple",
109            exp.DataType.Type.TINYINT: "Int8",
110            exp.DataType.Type.SMALLINT: "Int16",
111            exp.DataType.Type.INT: "Int32",
112            exp.DataType.Type.BIGINT: "Int64",
113            exp.DataType.Type.FLOAT: "Float32",
114            exp.DataType.Type.DOUBLE: "Float64",
115        }
116
117        TRANSFORMS = {
118            **generator.Generator.TRANSFORMS,  # type: ignore
119            exp.Array: inline_array_sql,
120            exp.StrPosition: lambda self, e: f"position({self.format_args(e.this, e.args.get('substr'), e.args.get('position'))})",
121            exp.Final: lambda self, e: f"{self.sql(e, 'this')} FINAL",
122            exp.Map: lambda self, e: _lower_func(var_map_sql(self, e)),
123            exp.VarMap: lambda self, e: _lower_func(var_map_sql(self, e)),
124            exp.Quantile: lambda self, e: f"quantile{self._param_args_sql(e, 'quantile', 'this')}",
125            exp.Quantiles: lambda self, e: f"quantiles{self._param_args_sql(e, 'parameters', 'expressions')}",
126            exp.QuantileIf: lambda self, e: f"quantileIf{self._param_args_sql(e, 'parameters', 'expressions')}",
127        }
128
129        EXPLICIT_UNION = True
130
131        def _param_args_sql(
132            self, expression: exp.Expression, params_name: str, args_name: str
133        ) -> str:
134            params = self.format_args(self.expressions(expression, params_name))
135            args = self.format_args(self.expressions(expression, args_name))
136            return f"({params})({args})"
137
138        def cte_sql(self, expression: exp.CTE) -> str:
139            if isinstance(expression.this, exp.Alias):
140                return self.sql(expression, "this")
141
142            return super().cte_sql(expression)

Generator interprets the given syntax tree and produces a SQL string as an output.

Arguments:

time_mapping (dict): the dictionary of custom time mappings in which the key represents a python time format and the output the target time format
time_trie (trie): a trie of the time_mapping keys
pretty (bool): if set to True the returned string will be formatted. Default: False.
quote_start (str): specifies which starting character to use to delimit quotes. Default: '.
quote_end (str): specifies which ending character to use to delimit quotes. Default: '.
identifier_start (str): specifies which starting character to use to delimit identifiers. Default: ".
identifier_end (str): specifies which ending character to use to delimit identifiers. Default: ".
identify (bool): if set to True all identifiers will be delimited by the corresponding character.
normalize (bool): if set to True all identifiers will lower cased
string_escape (str): specifies a string escape character. Default: '.
identifier_escape (str): specifies an identifier escape character. Default: ".
pad (int): determines padding in a formatted string. Default: 2.
indent (int): determines the size of indentation in a formatted string. Default: 4.
unnest_column_only (bool): if true unnest table aliases are considered only as column aliases
normalize_functions (str): normalize function names, "upper", "lower", or None Default: "upper"
alias_post_tablesample (bool): if the table alias comes after tablesample Default: False
unsupported_level (ErrorLevel): determines the generator's behavior when it encounters unsupported expressions. Default ErrorLevel.WARN.
null_ordering (str): Indicates the default null ordering method to use if not explicitly set. Options are "nulls_are_small", "nulls_are_large", "nulls_are_last". Default: "nulls_are_small"
max_unsupported (int): Maximum number of unsupported messages to include in a raised UnsupportedError. This is only relevant if unsupported_level is ErrorLevel.RAISE. Default: 3
leading_comma (bool): if the the comma is leading or trailing in select statements Default: False
max_text_width: The max number of characters in a segment before creating new lines in pretty mode. The default is on the smaller end because the length only represents a segment and not the true line length. Default: 80
comments: Whether or not to preserve comments in the output SQL code. Default: True

def cte_sql(self, expression: sqlglot.expressions.CTE) -> str: View Source

138        def cte_sql(self, expression: exp.CTE) -> str:
139            if isinstance(expression.this, exp.Alias):
140                return self.sql(expression, "this")
141
142            return super().cte_sql(expression)

Inherited Members

sqlglot.generator.Generator: Generator; generate; unsupported; sep; seg; pad_comment; maybe_comment; wrap; no_identify; normalize_func; indent; sql; uncache_sql; cache_sql; characterset_sql; column_sql; columndef_sql; columnconstraint_sql; autoincrementcolumnconstraint_sql; compresscolumnconstraint_sql; generatedasidentitycolumnconstraint_sql; notnullcolumnconstraint_sql; primarykeycolumnconstraint_sql; uniquecolumnconstraint_sql; create_sql; describe_sql; prepend_ctes; with_sql; tablealias_sql; bitstring_sql; hexstring_sql; datatype_sql; directory_sql; delete_sql; drop_sql; except_sql; except_op; fetch_sql; filter_sql; hint_sql; index_sql; identifier_sql; national_sql; partition_sql; properties_sql; root_properties; properties; with_properties; locate_properties; property_sql; likeproperty_sql; fallbackproperty_sql; journalproperty_sql; freespaceproperty_sql; afterjournalproperty_sql; checksumproperty_sql; mergeblockratioproperty_sql; datablocksizeproperty_sql; blockcompressionproperty_sql; isolatedloadingproperty_sql; lockingproperty_sql; withdataproperty_sql; insert_sql; intersect_sql; intersect_op; introducer_sql; pseudotype_sql; returning_sql; rowformatdelimitedproperty_sql; table_sql; tablesample_sql; pivot_sql; tuple_sql; update_sql; values_sql; var_sql; into_sql; from_sql; group_sql; having_sql; join_sql; lambda_sql; lateral_sql; limit_sql; offset_sql; lock_sql; literal_sql; loaddata_sql; null_sql; boolean_sql; order_sql; cluster_sql; distribute_sql; sort_sql; ordered_sql; matchrecognize_sql; query_modifiers; select_sql; schema_sql; star_sql; structkwarg_sql; parameter_sql; sessionparameter_sql; placeholder_sql; subquery_sql; qualify_sql; union_sql; union_op; unnest_sql; where_sql; window_sql; partition_by_sql; window_spec_sql; withingroup_sql; between_sql; bracket_sql; all_sql; any_sql; exists_sql; case_sql; constraint_sql; extract_sql; trim_sql; concat_sql; check_sql; foreignkey_sql; primarykey_sql; unique_sql; if_sql; in_sql; in_unnest_op; interval_sql; return_sql; reference_sql; anonymous_sql; paren_sql; neg_sql; not_sql; alias_sql; aliases_sql; attimezone_sql; add_sql; and_sql; connector_sql; bitwiseand_sql; bitwiseleftshift_sql; bitwisenot_sql; bitwiseor_sql; bitwiserightshift_sql; bitwisexor_sql; cast_sql; currentdate_sql; collate_sql; command_sql; comment_sql; transaction_sql; commit_sql; rollback_sql; altercolumn_sql; renametable_sql; altertable_sql; droppartition_sql; addconstraint_sql; distinct_sql; ignorenulls_sql; respectnulls_sql; intdiv_sql; dpipe_sql; div_sql; floatdiv_sql; overlaps_sql; distance_sql; dot_sql; eq_sql; escape_sql; glob_sql; gt_sql; gte_sql; ilike_sql; is_sql; like_sql; similarto_sql; lt_sql; lte_sql; mod_sql; mul_sql; neq_sql; nullsafeeq_sql; nullsafeneq_sql; or_sql; slice_sql; sub_sql; trycast_sql; use_sql; binary; function_fallback_sql; func; format_args; text_width; format_time; expressions; op_expressions; naked_property; set_operation; tag_sql; token_sql; userdefinedfunction_sql; joinhint_sql; kwarg_sql; when_sql; merge_sql