sqlglot.dialects.dialect API documentation

Edit on GitHub

# sqlglot.dialects.dialect

View Source

      1from __future__ import annotations
      2
      3import typing as t
      4from enum import Enum
      5
      6from sqlglot import exp
      7from sqlglot.generator import Generator
      8from sqlglot.helper import flatten, seq_get
      9from sqlglot.parser import Parser
     10from sqlglot.time import format_time
     11from sqlglot.tokens import Token, Tokenizer
     12from sqlglot.trie import new_trie
     13
     14E = t.TypeVar("E", bound=exp.Expression)
     15
     16
     17class Dialects(str, Enum):
     18    DIALECT = ""
     19
     20    BIGQUERY = "bigquery"
     21    CLICKHOUSE = "clickhouse"
     22    DUCKDB = "duckdb"
     23    HIVE = "hive"
     24    MYSQL = "mysql"
     25    ORACLE = "oracle"
     26    POSTGRES = "postgres"
     27    PRESTO = "presto"
     28    REDSHIFT = "redshift"
     29    SNOWFLAKE = "snowflake"
     30    SPARK = "spark"
     31    SPARK2 = "spark2"
     32    SQLITE = "sqlite"
     33    STARROCKS = "starrocks"
     34    TABLEAU = "tableau"
     35    TRINO = "trino"
     36    TSQL = "tsql"
     37    DATABRICKS = "databricks"
     38    DRILL = "drill"
     39    TERADATA = "teradata"
     40
     41
     42class _Dialect(type):
     43    classes: t.Dict[str, t.Type[Dialect]] = {}
     44
     45    @classmethod
     46    def __getitem__(cls, key: str) -> t.Type[Dialect]:
     47        return cls.classes[key]
     48
     49    @classmethod
     50    def get(
     51        cls, key: str, default: t.Optional[t.Type[Dialect]] = None
     52    ) -> t.Optional[t.Type[Dialect]]:
     53        return cls.classes.get(key, default)
     54
     55    def __new__(cls, clsname, bases, attrs):
     56        klass = super().__new__(cls, clsname, bases, attrs)
     57        enum = Dialects.__members__.get(clsname.upper())
     58        cls.classes[enum.value if enum is not None else clsname.lower()] = klass
     59
     60        klass.time_trie = new_trie(klass.time_mapping)
     61        klass.inverse_time_mapping = {v: k for k, v in klass.time_mapping.items()}
     62        klass.inverse_time_trie = new_trie(klass.inverse_time_mapping)
     63
     64        klass.tokenizer_class = getattr(klass, "Tokenizer", Tokenizer)
     65        klass.parser_class = getattr(klass, "Parser", Parser)
     66        klass.generator_class = getattr(klass, "Generator", Generator)
     67
     68        klass.quote_start, klass.quote_end = list(klass.tokenizer_class._QUOTES.items())[0]
     69        klass.identifier_start, klass.identifier_end = list(
     70            klass.tokenizer_class._IDENTIFIERS.items()
     71        )[0]
     72
     73        if (
     74            klass.tokenizer_class._BIT_STRINGS
     75            and exp.BitString not in klass.generator_class.TRANSFORMS
     76        ):
     77            bs_start, bs_end = list(klass.tokenizer_class._BIT_STRINGS.items())[0]
     78            klass.generator_class.TRANSFORMS[
     79                exp.BitString
     80            ] = lambda self, e: f"{bs_start}{int(self.sql(e, 'this')):b}{bs_end}"
     81        if (
     82            klass.tokenizer_class._HEX_STRINGS
     83            and exp.HexString not in klass.generator_class.TRANSFORMS
     84        ):
     85            hs_start, hs_end = list(klass.tokenizer_class._HEX_STRINGS.items())[0]
     86            klass.generator_class.TRANSFORMS[
     87                exp.HexString
     88            ] = lambda self, e: f"{hs_start}{int(self.sql(e, 'this')):X}{hs_end}"
     89        if (
     90            klass.tokenizer_class._BYTE_STRINGS
     91            and exp.ByteString not in klass.generator_class.TRANSFORMS
     92        ):
     93            be_start, be_end = list(klass.tokenizer_class._BYTE_STRINGS.items())[0]
     94            klass.generator_class.TRANSFORMS[
     95                exp.ByteString
     96            ] = lambda self, e: f"{be_start}{self.sql(e, 'this')}{be_end}"
     97
     98        return klass
     99
    100
    101class Dialect(metaclass=_Dialect):
    102    index_offset = 0
    103    unnest_column_only = False
    104    alias_post_tablesample = False
    105    normalize_functions: t.Optional[str] = "upper"
    106    null_ordering = "nulls_are_small"
    107
    108    date_format = "'%Y-%m-%d'"
    109    dateint_format = "'%Y%m%d'"
    110    time_format = "'%Y-%m-%d %H:%M:%S'"
    111    time_mapping: t.Dict[str, str] = {}
    112
    113    # autofilled
    114    quote_start = None
    115    quote_end = None
    116    identifier_start = None
    117    identifier_end = None
    118
    119    time_trie = None
    120    inverse_time_mapping = None
    121    inverse_time_trie = None
    122    tokenizer_class = None
    123    parser_class = None
    124    generator_class = None
    125
    126    @classmethod
    127    def get_or_raise(cls, dialect: DialectType) -> t.Type[Dialect]:
    128        if not dialect:
    129            return cls
    130        if isinstance(dialect, _Dialect):
    131            return dialect
    132        if isinstance(dialect, Dialect):
    133            return dialect.__class__
    134
    135        result = cls.get(dialect)
    136        if not result:
    137            raise ValueError(f"Unknown dialect '{dialect}'")
    138
    139        return result
    140
    141    @classmethod
    142    def format_time(
    143        cls, expression: t.Optional[str | exp.Expression]
    144    ) -> t.Optional[exp.Expression]:
    145        if isinstance(expression, str):
    146            return exp.Literal.string(
    147                format_time(
    148                    expression[1:-1],  # the time formats are quoted
    149                    cls.time_mapping,
    150                    cls.time_trie,
    151                )
    152            )
    153        if expression and expression.is_string:
    154            return exp.Literal.string(
    155                format_time(
    156                    expression.this,
    157                    cls.time_mapping,
    158                    cls.time_trie,
    159                )
    160            )
    161        return expression
    162
    163    def parse(self, sql: str, **opts) -> t.List[t.Optional[exp.Expression]]:
    164        return self.parser(**opts).parse(self.tokenize(sql), sql)
    165
    166    def parse_into(
    167        self, expression_type: exp.IntoType, sql: str, **opts
    168    ) -> t.List[t.Optional[exp.Expression]]:
    169        return self.parser(**opts).parse_into(expression_type, self.tokenize(sql), sql)
    170
    171    def generate(self, expression: t.Optional[exp.Expression], **opts) -> str:
    172        return self.generator(**opts).generate(expression)
    173
    174    def transpile(self, sql: str, **opts) -> t.List[str]:
    175        return [self.generate(expression, **opts) for expression in self.parse(sql)]
    176
    177    def tokenize(self, sql: str) -> t.List[Token]:
    178        return self.tokenizer.tokenize(sql)
    179
    180    @property
    181    def tokenizer(self) -> Tokenizer:
    182        if not hasattr(self, "_tokenizer"):
    183            self._tokenizer = self.tokenizer_class()  # type: ignore
    184        return self._tokenizer
    185
    186    def parser(self, **opts) -> Parser:
    187        return self.parser_class(  # type: ignore
    188            **{
    189                "index_offset": self.index_offset,
    190                "unnest_column_only": self.unnest_column_only,
    191                "alias_post_tablesample": self.alias_post_tablesample,
    192                "null_ordering": self.null_ordering,
    193                **opts,
    194            },
    195        )
    196
    197    def generator(self, **opts) -> Generator:
    198        return self.generator_class(  # type: ignore
    199            **{
    200                "quote_start": self.quote_start,
    201                "quote_end": self.quote_end,
    202                "identifier_start": self.identifier_start,
    203                "identifier_end": self.identifier_end,
    204                "string_escape": self.tokenizer_class.STRING_ESCAPES[0],
    205                "identifier_escape": self.tokenizer_class.IDENTIFIER_ESCAPES[0],
    206                "index_offset": self.index_offset,
    207                "time_mapping": self.inverse_time_mapping,
    208                "time_trie": self.inverse_time_trie,
    209                "unnest_column_only": self.unnest_column_only,
    210                "alias_post_tablesample": self.alias_post_tablesample,
    211                "normalize_functions": self.normalize_functions,
    212                "null_ordering": self.null_ordering,
    213                **opts,
    214            }
    215        )
    216
    217
    218DialectType = t.Union[str, Dialect, t.Type[Dialect], None]
    219
    220
    221def rename_func(name: str) -> t.Callable[[Generator, exp.Expression], str]:
    222    return lambda self, expression: self.func(name, *flatten(expression.args.values()))
    223
    224
    225def approx_count_distinct_sql(self: Generator, expression: exp.ApproxDistinct) -> str:
    226    if expression.args.get("accuracy"):
    227        self.unsupported("APPROX_COUNT_DISTINCT does not support accuracy")
    228    return self.func("APPROX_COUNT_DISTINCT", expression.this)
    229
    230
    231def if_sql(self: Generator, expression: exp.If) -> str:
    232    return self.func(
    233        "IF", expression.this, expression.args.get("true"), expression.args.get("false")
    234    )
    235
    236
    237def arrow_json_extract_sql(self: Generator, expression: exp.JSONExtract | exp.JSONBExtract) -> str:
    238    return self.binary(expression, "->")
    239
    240
    241def arrow_json_extract_scalar_sql(
    242    self: Generator, expression: exp.JSONExtractScalar | exp.JSONBExtractScalar
    243) -> str:
    244    return self.binary(expression, "->>")
    245
    246
    247def inline_array_sql(self: Generator, expression: exp.Array) -> str:
    248    return f"[{self.expressions(expression)}]"
    249
    250
    251def no_ilike_sql(self: Generator, expression: exp.ILike) -> str:
    252    return self.like_sql(
    253        exp.Like(
    254            this=exp.Lower(this=expression.this),
    255            expression=expression.args["expression"],
    256        )
    257    )
    258
    259
    260def no_paren_current_date_sql(self: Generator, expression: exp.CurrentDate) -> str:
    261    zone = self.sql(expression, "this")
    262    return f"CURRENT_DATE AT TIME ZONE {zone}" if zone else "CURRENT_DATE"
    263
    264
    265def no_recursive_cte_sql(self: Generator, expression: exp.With) -> str:
    266    if expression.args.get("recursive"):
    267        self.unsupported("Recursive CTEs are unsupported")
    268        expression.args["recursive"] = False
    269    return self.with_sql(expression)
    270
    271
    272def no_safe_divide_sql(self: Generator, expression: exp.SafeDivide) -> str:
    273    n = self.sql(expression, "this")
    274    d = self.sql(expression, "expression")
    275    return f"IF({d} <> 0, {n} / {d}, NULL)"
    276
    277
    278def no_tablesample_sql(self: Generator, expression: exp.TableSample) -> str:
    279    self.unsupported("TABLESAMPLE unsupported")
    280    return self.sql(expression.this)
    281
    282
    283def no_pivot_sql(self: Generator, expression: exp.Pivot) -> str:
    284    self.unsupported("PIVOT unsupported")
    285    return self.sql(expression)
    286
    287
    288def no_trycast_sql(self: Generator, expression: exp.TryCast) -> str:
    289    return self.cast_sql(expression)
    290
    291
    292def no_properties_sql(self: Generator, expression: exp.Properties) -> str:
    293    self.unsupported("Properties unsupported")
    294    return ""
    295
    296
    297def no_comment_column_constraint_sql(
    298    self: Generator, expression: exp.CommentColumnConstraint
    299) -> str:
    300    self.unsupported("CommentColumnConstraint unsupported")
    301    return ""
    302
    303
    304def str_position_sql(self: Generator, expression: exp.StrPosition) -> str:
    305    this = self.sql(expression, "this")
    306    substr = self.sql(expression, "substr")
    307    position = self.sql(expression, "position")
    308    if position:
    309        return f"STRPOS(SUBSTR({this}, {position}), {substr}) + {position} - 1"
    310    return f"STRPOS({this}, {substr})"
    311
    312
    313def struct_extract_sql(self: Generator, expression: exp.StructExtract) -> str:
    314    this = self.sql(expression, "this")
    315    struct_key = self.sql(exp.Identifier(this=expression.expression, quoted=True))
    316    return f"{this}.{struct_key}"
    317
    318
    319def var_map_sql(
    320    self: Generator, expression: exp.Map | exp.VarMap, map_func_name: str = "MAP"
    321) -> str:
    322    keys = expression.args["keys"]
    323    values = expression.args["values"]
    324
    325    if not isinstance(keys, exp.Array) or not isinstance(values, exp.Array):
    326        self.unsupported("Cannot convert array columns into map.")
    327        return self.func(map_func_name, keys, values)
    328
    329    args = []
    330    for key, value in zip(keys.expressions, values.expressions):
    331        args.append(self.sql(key))
    332        args.append(self.sql(value))
    333    return self.func(map_func_name, *args)
    334
    335
    336def format_time_lambda(
    337    exp_class: t.Type[E], dialect: str, default: t.Optional[bool | str] = None
    338) -> t.Callable[[t.Sequence], E]:
    339    """Helper used for time expressions.
    340
    341    Args:
    342        exp_class: the expression class to instantiate.
    343        dialect: target sql dialect.
    344        default: the default format, True being time.
    345
    346    Returns:
    347        A callable that can be used to return the appropriately formatted time expression.
    348    """
    349
    350    def _format_time(args: t.Sequence):
    351        return exp_class(
    352            this=seq_get(args, 0),
    353            format=Dialect[dialect].format_time(
    354                seq_get(args, 1)
    355                or (Dialect[dialect].time_format if default is True else default or None)
    356            ),
    357        )
    358
    359    return _format_time
    360
    361
    362def create_with_partitions_sql(self: Generator, expression: exp.Create) -> str:
    363    """
    364    In Hive and Spark, the PARTITIONED BY property acts as an extension of a table's schema. When the
    365    PARTITIONED BY value is an array of column names, they are transformed into a schema. The corresponding
    366    columns are removed from the create statement.
    367    """
    368    has_schema = isinstance(expression.this, exp.Schema)
    369    is_partitionable = expression.args.get("kind") in ("TABLE", "VIEW")
    370
    371    if has_schema and is_partitionable:
    372        expression = expression.copy()
    373        prop = expression.find(exp.PartitionedByProperty)
    374        if prop and prop.this and not isinstance(prop.this, exp.Schema):
    375            schema = expression.this
    376            columns = {v.name.upper() for v in prop.this.expressions}
    377            partitions = [col for col in schema.expressions if col.name.upper() in columns]
    378            schema.set("expressions", [e for e in schema.expressions if e not in partitions])
    379            prop.replace(exp.PartitionedByProperty(this=exp.Schema(expressions=partitions)))
    380            expression.set("this", schema)
    381
    382    return self.create_sql(expression)
    383
    384
    385def parse_date_delta(
    386    exp_class: t.Type[E], unit_mapping: t.Optional[t.Dict[str, str]] = None
    387) -> t.Callable[[t.Sequence], E]:
    388    def inner_func(args: t.Sequence) -> E:
    389        unit_based = len(args) == 3
    390        this = args[2] if unit_based else seq_get(args, 0)
    391        unit = args[0] if unit_based else exp.Literal.string("DAY")
    392        unit = unit_mapping.get(unit.name.lower(), unit) if unit_mapping else unit
    393        return exp_class(this=this, expression=seq_get(args, 1), unit=unit)
    394
    395    return inner_func
    396
    397
    398def parse_date_delta_with_interval(
    399    expression_class: t.Type[E],
    400) -> t.Callable[[t.Sequence], t.Optional[E]]:
    401    def func(args: t.Sequence) -> t.Optional[E]:
    402        if len(args) < 2:
    403            return None
    404
    405        interval = args[1]
    406        expression = interval.this
    407        if expression and expression.is_string:
    408            expression = exp.Literal.number(expression.this)
    409
    410        return expression_class(
    411            this=args[0],
    412            expression=expression,
    413            unit=exp.Literal.string(interval.text("unit")),
    414        )
    415
    416    return func
    417
    418
    419def date_trunc_to_time(args: t.Sequence) -> exp.DateTrunc | exp.TimestampTrunc:
    420    unit = seq_get(args, 0)
    421    this = seq_get(args, 1)
    422
    423    if isinstance(this, exp.Cast) and this.is_type(exp.DataType.Type.DATE):
    424        return exp.DateTrunc(unit=unit, this=this)
    425    return exp.TimestampTrunc(this=this, unit=unit)
    426
    427
    428def timestamptrunc_sql(self: Generator, expression: exp.TimestampTrunc) -> str:
    429    return self.func(
    430        "DATE_TRUNC", exp.Literal.string(expression.text("unit") or "day"), expression.this
    431    )
    432
    433
    434def locate_to_strposition(args: t.Sequence) -> exp.Expression:
    435    return exp.StrPosition(
    436        this=seq_get(args, 1),
    437        substr=seq_get(args, 0),
    438        position=seq_get(args, 2),
    439    )
    440
    441
    442def strposition_to_locate_sql(self: Generator, expression: exp.StrPosition) -> str:
    443    return self.func(
    444        "LOCATE", expression.args.get("substr"), expression.this, expression.args.get("position")
    445    )
    446
    447
    448def timestrtotime_sql(self: Generator, expression: exp.TimeStrToTime) -> str:
    449    return f"CAST({self.sql(expression, 'this')} AS TIMESTAMP)"
    450
    451
    452def datestrtodate_sql(self: Generator, expression: exp.DateStrToDate) -> str:
    453    return f"CAST({self.sql(expression, 'this')} AS DATE)"
    454
    455
    456def min_or_least(self: Generator, expression: exp.Min) -> str:
    457    name = "LEAST" if expression.expressions else "MIN"
    458    return rename_func(name)(self, expression)
    459
    460
    461def max_or_greatest(self: Generator, expression: exp.Max) -> str:
    462    name = "GREATEST" if expression.expressions else "MAX"
    463    return rename_func(name)(self, expression)
    464
    465
    466def count_if_to_sum(self: Generator, expression: exp.CountIf) -> str:
    467    cond = expression.this
    468
    469    if isinstance(expression.this, exp.Distinct):
    470        cond = expression.this.expressions[0]
    471        self.unsupported("DISTINCT is not supported when converting COUNT_IF to SUM")
    472
    473    return self.func("sum", exp.func("if", cond, 1, 0))
    474
    475
    476def trim_sql(self: Generator, expression: exp.Trim) -> str:
    477    target = self.sql(expression, "this")
    478    trim_type = self.sql(expression, "position")
    479    remove_chars = self.sql(expression, "expression")
    480    collation = self.sql(expression, "collation")
    481
    482    # Use TRIM/LTRIM/RTRIM syntax if the expression isn't database-specific
    483    if not remove_chars and not collation:
    484        return self.trim_sql(expression)
    485
    486    trim_type = f"{trim_type} " if trim_type else ""
    487    remove_chars = f"{remove_chars} " if remove_chars else ""
    488    from_part = "FROM " if trim_type or remove_chars else ""
    489    collation = f" COLLATE {collation}" if collation else ""
    490    return f"TRIM({trim_type}{remove_chars}{from_part}{target}{collation})"
    491
    492
    493def str_to_time_sql(self, expression: exp.Expression) -> str:
    494    return self.func("STRPTIME", expression.this, self.format_time(expression))
    495
    496
    497def ts_or_ds_to_date_sql(dialect: str) -> t.Callable:
    498    def _ts_or_ds_to_date_sql(self: Generator, expression: exp.TsOrDsToDate) -> str:
    499        _dialect = Dialect.get_or_raise(dialect)
    500        time_format = self.format_time(expression)
    501        if time_format and time_format not in (_dialect.time_format, _dialect.date_format):
    502            return f"CAST({str_to_time_sql(self, expression)} AS DATE)"
    503        return f"CAST({self.sql(expression, 'this')} AS DATE)"
    504
    505    return _ts_or_ds_to_date_sql

class Dialects(builtins.str, enum.Enum): View Source

    18class Dialects(str, Enum):
    19    DIALECT = ""
    20
    21    BIGQUERY = "bigquery"
    22    CLICKHOUSE = "clickhouse"
    23    DUCKDB = "duckdb"
    24    HIVE = "hive"
    25    MYSQL = "mysql"
    26    ORACLE = "oracle"
    27    POSTGRES = "postgres"
    28    PRESTO = "presto"
    29    REDSHIFT = "redshift"
    30    SNOWFLAKE = "snowflake"
    31    SPARK = "spark"
    32    SPARK2 = "spark2"
    33    SQLITE = "sqlite"
    34    STARROCKS = "starrocks"
    35    TABLEAU = "tableau"
    36    TRINO = "trino"
    37    TSQL = "tsql"
    38    DATABRICKS = "databricks"
    39    DRILL = "drill"
    40    TERADATA = "teradata"

An enumeration.

DIALECT = <Dialects.DIALECT: ''>
BIGQUERY = <Dialects.BIGQUERY: 'bigquery'>
CLICKHOUSE = <Dialects.CLICKHOUSE: 'clickhouse'>
DUCKDB = <Dialects.DUCKDB: 'duckdb'>
HIVE = <Dialects.HIVE: 'hive'>
MYSQL = <Dialects.MYSQL: 'mysql'>
ORACLE = <Dialects.ORACLE: 'oracle'>
POSTGRES = <Dialects.POSTGRES: 'postgres'>
PRESTO = <Dialects.PRESTO: 'presto'>
REDSHIFT = <Dialects.REDSHIFT: 'redshift'>
SNOWFLAKE = <Dialects.SNOWFLAKE: 'snowflake'>
SPARK = <Dialects.SPARK: 'spark'>
SPARK2 = <Dialects.SPARK2: 'spark2'>
SQLITE = <Dialects.SQLITE: 'sqlite'>
STARROCKS = <Dialects.STARROCKS: 'starrocks'>
TABLEAU = <Dialects.TABLEAU: 'tableau'>
TRINO = <Dialects.TRINO: 'trino'>
TSQL = <Dialects.TSQL: 'tsql'>
DATABRICKS = <Dialects.DATABRICKS: 'databricks'>
DRILL = <Dialects.DRILL: 'drill'>
TERADATA = <Dialects.TERADATA: 'teradata'>

##### Inherited Members

enum.Enum
  name
  value
builtins.str
  encode
  replace
  split
  rsplit
  join
  capitalize
  casefold
  title
  center
  count
  expandtabs
  find
  partition
  index
  ljust
  lower
  lstrip
  rfind
  rindex
  rjust
  rstrip
  rpartition
  splitlines
  strip
  swapcase
  translate
  upper
  startswith
  endswith
  removeprefix
  removesuffix
  isascii
  islower
  isupper
  istitle
  isspace
  isdecimal
  isdigit
  isnumeric
  isalpha
  isalnum
  isidentifier
  isprintable
  zfill
  format
  format_map
  maketrans

class Dialect: View Source

    102class Dialect(metaclass=_Dialect):
    103    index_offset = 0
    104    unnest_column_only = False
    105    alias_post_tablesample = False
    106    normalize_functions: t.Optional[str] = "upper"
    107    null_ordering = "nulls_are_small"
    108
    109    date_format = "'%Y-%m-%d'"
    110    dateint_format = "'%Y%m%d'"
    111    time_format = "'%Y-%m-%d %H:%M:%S'"
    112    time_mapping: t.Dict[str, str] = {}
    113
    114    # autofilled
    115    quote_start = None
    116    quote_end = None
    117    identifier_start = None
    118    identifier_end = None
    119
    120    time_trie = None
    121    inverse_time_mapping = None
    122    inverse_time_trie = None
    123    tokenizer_class = None
    124    parser_class = None
    125    generator_class = None
    126
    127    @classmethod
    128    def get_or_raise(cls, dialect: DialectType) -> t.Type[Dialect]:
    129        if not dialect:
    130            return cls
    131        if isinstance(dialect, _Dialect):
    132            return dialect
    133        if isinstance(dialect, Dialect):
    134            return dialect.__class__
    135
    136        result = cls.get(dialect)
    137        if not result:
    138            raise ValueError(f"Unknown dialect '{dialect}'")
    139
    140        return result
    141
    142    @classmethod
    143    def format_time(
    144        cls, expression: t.Optional[str | exp.Expression]
    145    ) -> t.Optional[exp.Expression]:
    146        if isinstance(expression, str):
    147            return exp.Literal.string(
    148                format_time(
    149                    expression[1:-1],  # the time formats are quoted
    150                    cls.time_mapping,
    151                    cls.time_trie,
    152                )
    153            )
    154        if expression and expression.is_string:
    155            return exp.Literal.string(
    156                format_time(
    157                    expression.this,
    158                    cls.time_mapping,
    159                    cls.time_trie,
    160                )
    161            )
    162        return expression
    163
    164    def parse(self, sql: str, **opts) -> t.List[t.Optional[exp.Expression]]:
    165        return self.parser(**opts).parse(self.tokenize(sql), sql)
    166
    167    def parse_into(
    168        self, expression_type: exp.IntoType, sql: str, **opts
    169    ) -> t.List[t.Optional[exp.Expression]]:
    170        return self.parser(**opts).parse_into(expression_type, self.tokenize(sql), sql)
    171
    172    def generate(self, expression: t.Optional[exp.Expression], **opts) -> str:
    173        return self.generator(**opts).generate(expression)
    174
    175    def transpile(self, sql: str, **opts) -> t.List[str]:
    176        return [self.generate(expression, **opts) for expression in self.parse(sql)]
    177
    178    def tokenize(self, sql: str) -> t.List[Token]:
    179        return self.tokenizer.tokenize(sql)
    180
    181    @property
    182    def tokenizer(self) -> Tokenizer:
    183        if not hasattr(self, "_tokenizer"):
    184            self._tokenizer = self.tokenizer_class()  # type: ignore
    185        return self._tokenizer
    186
    187    def parser(self, **opts) -> Parser:
    188        return self.parser_class(  # type: ignore
    189            **{
    190                "index_offset": self.index_offset,
    191                "unnest_column_only": self.unnest_column_only,
    192                "alias_post_tablesample": self.alias_post_tablesample,
    193                "null_ordering": self.null_ordering,
    194                **opts,
    195            },
    196        )
    197
    198    def generator(self, **opts) -> Generator:
    199        return self.generator_class(  # type: ignore
    200            **{
    201                "quote_start": self.quote_start,
    202                "quote_end": self.quote_end,
    203                "identifier_start": self.identifier_start,
    204                "identifier_end": self.identifier_end,
    205                "string_escape": self.tokenizer_class.STRING_ESCAPES[0],
    206                "identifier_escape": self.tokenizer_class.IDENTIFIER_ESCAPES[0],
    207                "index_offset": self.index_offset,
    208                "time_mapping": self.inverse_time_mapping,
    209                "time_trie": self.inverse_time_trie,
    210                "unnest_column_only": self.unnest_column_only,
    211                "alias_post_tablesample": self.alias_post_tablesample,
    212                "normalize_functions": self.normalize_functions,
    213                "null_ordering": self.null_ordering,
    214                **opts,
    215            }
    216        )

@classmethod
def get_or_raise( cls, dialect: Union[str, sqlglot.dialects.dialect.Dialect, Type[sqlglot.dialects.dialect.Dialect], NoneType]) -> Type[sqlglot.dialects.dialect.Dialect]: View Source

    127    @classmethod
    128    def get_or_raise(cls, dialect: DialectType) -> t.Type[Dialect]:
    129        if not dialect:
    130            return cls
    131        if isinstance(dialect, _Dialect):
    132            return dialect
    133        if isinstance(dialect, Dialect):
    134            return dialect.__class__
    135
    136        result = cls.get(dialect)
    137        if not result:
    138            raise ValueError(f"Unknown dialect '{dialect}'")
    139
    140        return result

@classmethod
def format_time( cls, expression: Union[str, sqlglot.expressions.Expression, NoneType]) -> Optional[sqlglot.expressions.Expression]: View Source

    142    @classmethod
    143    def format_time(
    144        cls, expression: t.Optional[str | exp.Expression]
    145    ) -> t.Optional[exp.Expression]:
    146        if isinstance(expression, str):
    147            return exp.Literal.string(
    148                format_time(
    149                    expression[1:-1],  # the time formats are quoted
    150                    cls.time_mapping,
    151                    cls.time_trie,
    152                )
    153            )
    154        if expression and expression.is_string:
    155            return exp.Literal.string(
    156                format_time(
    157                    expression.this,
    158                    cls.time_mapping,
    159                    cls.time_trie,
    160                )
    161            )
    162        return expression

def parse(self, sql: str, **opts) -> List[Optional[sqlglot.expressions.Expression]]: View Source

    164    def parse(self, sql: str, **opts) -> t.List[t.Optional[exp.Expression]]:
    165        return self.parser(**opts).parse(self.tokenize(sql), sql)

def parse_into( self, expression_type: Union[str, Type[sqlglot.expressions.Expression], Collection[Union[str, Type[sqlglot.expressions.Expression]]]], sql: str, **opts) -> List[Optional[sqlglot.expressions.Expression]]: View Source

    167    def parse_into(
    168        self, expression_type: exp.IntoType, sql: str, **opts
    169    ) -> t.List[t.Optional[exp.Expression]]:
    170        return self.parser(**opts).parse_into(expression_type, self.tokenize(sql), sql)

def generate( self, expression: Optional[sqlglot.expressions.Expression], **opts) -> str: View Source

    172    def generate(self, expression: t.Optional[exp.Expression], **opts) -> str:
    173        return self.generator(**opts).generate(expression)

def transpile(self, sql: str, **opts) -> List[str]: View Source

    175    def transpile(self, sql: str, **opts) -> t.List[str]:
    176        return [self.generate(expression, **opts) for expression in self.parse(sql)]

def tokenize(self, sql: str) -> List[sqlglot.tokens.Token]: View Source

    178    def tokenize(self, sql: str) -> t.List[Token]:
    179        return self.tokenizer.tokenize(sql)

def parser(self, **opts) -> sqlglot.parser.Parser: View Source

    187    def parser(self, **opts) -> Parser:
    188        return self.parser_class(  # type: ignore
    189            **{
    190                "index_offset": self.index_offset,
    191                "unnest_column_only": self.unnest_column_only,
    192                "alias_post_tablesample": self.alias_post_tablesample,
    193                "null_ordering": self.null_ordering,
    194                **opts,
    195            },
    196        )

def generator(self, **opts) -> sqlglot.generator.Generator: View Source

    198    def generator(self, **opts) -> Generator:
    199        return self.generator_class(  # type: ignore
    200            **{
    201                "quote_start": self.quote_start,
    202                "quote_end": self.quote_end,
    203                "identifier_start": self.identifier_start,
    204                "identifier_end": self.identifier_end,
    205                "string_escape": self.tokenizer_class.STRING_ESCAPES[0],
    206                "identifier_escape": self.tokenizer_class.IDENTIFIER_ESCAPES[0],
    207                "index_offset": self.index_offset,
    208                "time_mapping": self.inverse_time_mapping,
    209                "time_trie": self.inverse_time_trie,
    210                "unnest_column_only": self.unnest_column_only,
    211                "alias_post_tablesample": self.alias_post_tablesample,
    212                "normalize_functions": self.normalize_functions,
    213                "null_ordering": self.null_ordering,
    214                **opts,
    215            }
    216        )

def rename_func( name: str) -> Callable[[sqlglot.generator.Generator, sqlglot.expressions.Expression], str]: View Source

    222def rename_func(name: str) -> t.Callable[[Generator, exp.Expression], str]:
    223    return lambda self, expression: self.func(name, *flatten(expression.args.values()))

def approx_count_distinct_sql( self: sqlglot.generator.Generator, expression: sqlglot.expressions.ApproxDistinct) -> str: View Source

    226def approx_count_distinct_sql(self: Generator, expression: exp.ApproxDistinct) -> str:
    227    if expression.args.get("accuracy"):
    228        self.unsupported("APPROX_COUNT_DISTINCT does not support accuracy")
    229    return self.func("APPROX_COUNT_DISTINCT", expression.this)

def if_sql( self: sqlglot.generator.Generator, expression: sqlglot.expressions.If) -> str: View Source

    232def if_sql(self: Generator, expression: exp.If) -> str:
    233    return self.func(
    234        "IF", expression.this, expression.args.get("true"), expression.args.get("false")
    235    )

def arrow_json_extract_sql( self: sqlglot.generator.Generator, expression: sqlglot.expressions.JSONExtract | sqlglot.expressions.JSONBExtract) -> str: View Source

    238def arrow_json_extract_sql(self: Generator, expression: exp.JSONExtract | exp.JSONBExtract) -> str:
    239    return self.binary(expression, "->")

def arrow_json_extract_scalar_sql( self: sqlglot.generator.Generator, expression: sqlglot.expressions.JSONExtractScalar | sqlglot.expressions.JSONBExtractScalar) -> str: View Source

    242def arrow_json_extract_scalar_sql(
    243    self: Generator, expression: exp.JSONExtractScalar | exp.JSONBExtractScalar
    244) -> str:
    245    return self.binary(expression, "->>")

def inline_array_sql( self: sqlglot.generator.Generator, expression: sqlglot.expressions.Array) -> str: View Source

    248def inline_array_sql(self: Generator, expression: exp.Array) -> str:
    249    return f"[{self.expressions(expression)}]"

def no_ilike_sql( self: sqlglot.generator.Generator, expression: sqlglot.expressions.ILike) -> str: View Source

    252def no_ilike_sql(self: Generator, expression: exp.ILike) -> str:
    253    return self.like_sql(
    254        exp.Like(
    255            this=exp.Lower(this=expression.this),
    256            expression=expression.args["expression"],
    257        )
    258    )

def no_paren_current_date_sql( self: sqlglot.generator.Generator, expression: sqlglot.expressions.CurrentDate) -> str: View Source

    261def no_paren_current_date_sql(self: Generator, expression: exp.CurrentDate) -> str:
    262    zone = self.sql(expression, "this")
    263    return f"CURRENT_DATE AT TIME ZONE {zone}" if zone else "CURRENT_DATE"

def no_recursive_cte_sql( self: sqlglot.generator.Generator, expression: sqlglot.expressions.With) -> str: View Source

    266def no_recursive_cte_sql(self: Generator, expression: exp.With) -> str:
    267    if expression.args.get("recursive"):
    268        self.unsupported("Recursive CTEs are unsupported")
    269        expression.args["recursive"] = False
    270    return self.with_sql(expression)

def no_safe_divide_sql( self: sqlglot.generator.Generator, expression: sqlglot.expressions.SafeDivide) -> str: View Source

    273def no_safe_divide_sql(self: Generator, expression: exp.SafeDivide) -> str:
    274    n = self.sql(expression, "this")
    275    d = self.sql(expression, "expression")
    276    return f"IF({d} <> 0, {n} / {d}, NULL)"

def no_tablesample_sql( self: sqlglot.generator.Generator, expression: sqlglot.expressions.TableSample) -> str: View Source

    279def no_tablesample_sql(self: Generator, expression: exp.TableSample) -> str:
    280    self.unsupported("TABLESAMPLE unsupported")
    281    return self.sql(expression.this)

def no_pivot_sql( self: sqlglot.generator.Generator, expression: sqlglot.expressions.Pivot) -> str: View Source

    284def no_pivot_sql(self: Generator, expression: exp.Pivot) -> str:
    285    self.unsupported("PIVOT unsupported")
    286    return self.sql(expression)

def no_trycast_sql( self: sqlglot.generator.Generator, expression: sqlglot.expressions.TryCast) -> str: View Source

    289def no_trycast_sql(self: Generator, expression: exp.TryCast) -> str:
    290    return self.cast_sql(expression)

def no_properties_sql( self: sqlglot.generator.Generator, expression: sqlglot.expressions.Properties) -> str: View Source

    293def no_properties_sql(self: Generator, expression: exp.Properties) -> str:
    294    self.unsupported("Properties unsupported")
    295    return ""

def no_comment_column_constraint_sql( self: sqlglot.generator.Generator, expression: sqlglot.expressions.CommentColumnConstraint) -> str: View Source

    298def no_comment_column_constraint_sql(
    299    self: Generator, expression: exp.CommentColumnConstraint
    300) -> str:
    301    self.unsupported("CommentColumnConstraint unsupported")
    302    return ""

def str_position_sql( self: sqlglot.generator.Generator, expression: sqlglot.expressions.StrPosition) -> str: View Source

    305def str_position_sql(self: Generator, expression: exp.StrPosition) -> str:
    306    this = self.sql(expression, "this")
    307    substr = self.sql(expression, "substr")
    308    position = self.sql(expression, "position")
    309    if position:
    310        return f"STRPOS(SUBSTR({this}, {position}), {substr}) + {position} - 1"
    311    return f"STRPOS({this}, {substr})"

def struct_extract_sql( self: sqlglot.generator.Generator, expression: sqlglot.expressions.StructExtract) -> str: View Source

    314def struct_extract_sql(self: Generator, expression: exp.StructExtract) -> str:
    315    this = self.sql(expression, "this")
    316    struct_key = self.sql(exp.Identifier(this=expression.expression, quoted=True))
    317    return f"{this}.{struct_key}"

def var_map_sql( self: sqlglot.generator.Generator, expression: sqlglot.expressions.Map | sqlglot.expressions.VarMap, map_func_name: str = 'MAP') -> str: View Source

    320def var_map_sql(
    321    self: Generator, expression: exp.Map | exp.VarMap, map_func_name: str = "MAP"
    322) -> str:
    323    keys = expression.args["keys"]
    324    values = expression.args["values"]
    325
    326    if not isinstance(keys, exp.Array) or not isinstance(values, exp.Array):
    327        self.unsupported("Cannot convert array columns into map.")
    328        return self.func(map_func_name, keys, values)
    329
    330    args = []
    331    for key, value in zip(keys.expressions, values.expressions):
    332        args.append(self.sql(key))
    333        args.append(self.sql(value))
    334    return self.func(map_func_name, *args)

def format_time_lambda( exp_class: Type[~E], dialect: str, default: Union[bool, str, NoneType] = None) -> Callable[[Sequence], ~E]: View Source

    337def format_time_lambda(
    338    exp_class: t.Type[E], dialect: str, default: t.Optional[bool | str] = None
    339) -> t.Callable[[t.Sequence], E]:
    340    """Helper used for time expressions.
    341
    342    Args:
    343        exp_class: the expression class to instantiate.
    344        dialect: target sql dialect.
    345        default: the default format, True being time.
    346
    347    Returns:
    348        A callable that can be used to return the appropriately formatted time expression.
    349    """
    350
    351    def _format_time(args: t.Sequence):
    352        return exp_class(
    353            this=seq_get(args, 0),
    354            format=Dialect[dialect].format_time(
    355                seq_get(args, 1)
    356                or (Dialect[dialect].time_format if default is True else default or None)
    357            ),
    358        )
    359
    360    return _format_time

Helper used for time expressions.

###### Arguments:

- exp_class: the expression class to instantiate.
- dialect: target sql dialect.
- default: the default format, True being time.

###### Returns:

> A callable that can be used to return the appropriately formatted time expression.

def create_with_partitions_sql( self: sqlglot.generator.Generator, expression: sqlglot.expressions.Create) -> str: View Source

    363def create_with_partitions_sql(self: Generator, expression: exp.Create) -> str:
    364    """
    365    In Hive and Spark, the PARTITIONED BY property acts as an extension of a table's schema. When the
    366    PARTITIONED BY value is an array of column names, they are transformed into a schema. The corresponding
    367    columns are removed from the create statement.
    368    """
    369    has_schema = isinstance(expression.this, exp.Schema)
    370    is_partitionable = expression.args.get("kind") in ("TABLE", "VIEW")
    371
    372    if has_schema and is_partitionable:
    373        expression = expression.copy()
    374        prop = expression.find(exp.PartitionedByProperty)
    375        if prop and prop.this and not isinstance(prop.this, exp.Schema):
    376            schema = expression.this
    377            columns = {v.name.upper() for v in prop.this.expressions}
    378            partitions = [col for col in schema.expressions if col.name.upper() in columns]
    379            schema.set("expressions", [e for e in schema.expressions if e not in partitions])
    380            prop.replace(exp.PartitionedByProperty(this=exp.Schema(expressions=partitions)))
    381            expression.set("this", schema)
    382
    383    return self.create_sql(expression)

In Hive and Spark, the PARTITIONED BY property acts as an extension of a table's schema. When the PARTITIONED BY value is an array of column names, they are transformed into a schema. The corresponding columns are removed from the create statement.

def parse_date_delta( exp_class: Type[~E], unit_mapping: Optional[Dict[str, str]] = None) -> Callable[[Sequence], ~E]: View Source

    386def parse_date_delta(
    387    exp_class: t.Type[E], unit_mapping: t.Optional[t.Dict[str, str]] = None
    388) -> t.Callable[[t.Sequence], E]:
    389    def inner_func(args: t.Sequence) -> E:
    390        unit_based = len(args) == 3
    391        this = args[2] if unit_based else seq_get(args, 0)
    392        unit = args[0] if unit_based else exp.Literal.string("DAY")
    393        unit = unit_mapping.get(unit.name.lower(), unit) if unit_mapping else unit
    394        return exp_class(this=this, expression=seq_get(args, 1), unit=unit)
    395
    396    return inner_func

def parse_date_delta_with_interval(expression_class: Type[~E]) -> Callable[[Sequence], Optional[~E]]: View Source

    399def parse_date_delta_with_interval(
    400    expression_class: t.Type[E],
    401) -> t.Callable[[t.Sequence], t.Optional[E]]:
    402    def func(args: t.Sequence) -> t.Optional[E]:
    403        if len(args) < 2:
    404            return None
    405
    406        interval = args[1]
    407        expression = interval.this
    408        if expression and expression.is_string:
    409            expression = exp.Literal.number(expression.this)
    410
    411        return expression_class(
    412            this=args[0],
    413            expression=expression,
    414            unit=exp.Literal.string(interval.text("unit")),
    415        )
    416
    417    return func

def date_trunc_to_time( args: Sequence) -> sqlglot.expressions.DateTrunc | sqlglot.expressions.TimestampTrunc: View Source

    420def date_trunc_to_time(args: t.Sequence) -> exp.DateTrunc | exp.TimestampTrunc:
    421    unit = seq_get(args, 0)
    422    this = seq_get(args, 1)
    423
    424    if isinstance(this, exp.Cast) and this.is_type(exp.DataType.Type.DATE):
    425        return exp.DateTrunc(unit=unit, this=this)
    426    return exp.TimestampTrunc(this=this, unit=unit)

def timestamptrunc_sql( self: sqlglot.generator.Generator, expression: sqlglot.expressions.TimestampTrunc) -> str: View Source

    429def timestamptrunc_sql(self: Generator, expression: exp.TimestampTrunc) -> str:
    430    return self.func(
    431        "DATE_TRUNC", exp.Literal.string(expression.text("unit") or "day"), expression.this
    432    )

def locate_to_strposition(args: Sequence) -> sqlglot.expressions.Expression: View Source

    435def locate_to_strposition(args: t.Sequence) -> exp.Expression:
    436    return exp.StrPosition(
    437        this=seq_get(args, 1),
    438        substr=seq_get(args, 0),
    439        position=seq_get(args, 2),
    440    )

def strposition_to_locate_sql( self: sqlglot.generator.Generator, expression: sqlglot.expressions.StrPosition) -> str: View Source

    443def strposition_to_locate_sql(self: Generator, expression: exp.StrPosition) -> str:
    444    return self.func(
    445        "LOCATE", expression.args.get("substr"), expression.this, expression.args.get("position")
    446    )

def timestrtotime_sql( self: sqlglot.generator.Generator, expression: sqlglot.expressions.TimeStrToTime) -> str: View Source

    449def timestrtotime_sql(self: Generator, expression: exp.TimeStrToTime) -> str:
    450    return f"CAST({self.sql(expression, 'this')} AS TIMESTAMP)"

def datestrtodate_sql( self: sqlglot.generator.Generator, expression: sqlglot.expressions.DateStrToDate) -> str: View Source

    453def datestrtodate_sql(self: Generator, expression: exp.DateStrToDate) -> str:
    454    return f"CAST({self.sql(expression, 'this')} AS DATE)"

def min_or_least( self: sqlglot.generator.Generator, expression: sqlglot.expressions.Min) -> str: View Source

    457def min_or_least(self: Generator, expression: exp.Min) -> str:
    458    name = "LEAST" if expression.expressions else "MIN"
    459    return rename_func(name)(self, expression)

def max_or_greatest( self: sqlglot.generator.Generator, expression: sqlglot.expressions.Max) -> str: View Source

    462def max_or_greatest(self: Generator, expression: exp.Max) -> str:
    463    name = "GREATEST" if expression.expressions else "MAX"
    464    return rename_func(name)(self, expression)

def count_if_to_sum( self: sqlglot.generator.Generator, expression: sqlglot.expressions.CountIf) -> str: View Source

    467def count_if_to_sum(self: Generator, expression: exp.CountIf) -> str:
    468    cond = expression.this
    469
    470    if isinstance(expression.this, exp.Distinct):
    471        cond = expression.this.expressions[0]
    472        self.unsupported("DISTINCT is not supported when converting COUNT_IF to SUM")
    473
    474    return self.func("sum", exp.func("if", cond, 1, 0))

def trim_sql( self: sqlglot.generator.Generator, expression: sqlglot.expressions.Trim) -> str: View Source

    477def trim_sql(self: Generator, expression: exp.Trim) -> str:
    478    target = self.sql(expression, "this")
    479    trim_type = self.sql(expression, "position")
    480    remove_chars = self.sql(expression, "expression")
    481    collation = self.sql(expression, "collation")
    482
    483    # Use TRIM/LTRIM/RTRIM syntax if the expression isn't database-specific
    484    if not remove_chars and not collation:
    485        return self.trim_sql(expression)
    486
    487    trim_type = f"{trim_type} " if trim_type else ""
    488    remove_chars = f"{remove_chars} " if remove_chars else ""
    489    from_part = "FROM " if trim_type or remove_chars else ""
    490    collation = f" COLLATE {collation}" if collation else ""
    491    return f"TRIM({trim_type}{remove_chars}{from_part}{target}{collation})"

def str_to_time_sql(self, expression: sqlglot.expressions.Expression) -> str: View Source

    494def str_to_time_sql(self, expression: exp.Expression) -> str:
    495    return self.func("STRPTIME", expression.this, self.format_time(expression))

def ts_or_ds_to_date_sql(dialect: str) -> Callable: View Source

    498def ts_or_ds_to_date_sql(dialect: str) -> t.Callable:
    499    def _ts_or_ds_to_date_sql(self: Generator, expression: exp.TsOrDsToDate) -> str:
    500        _dialect = Dialect.get_or_raise(dialect)
    501        time_format = self.format_time(expression)
    502        if time_format and time_format not in (_dialect.time_format, _dialect.date_format):
    503            return f"CAST({str_to_time_sql(self, expression)} AS DATE)"
    504        return f"CAST({self.sql(expression, 'this')} AS DATE)"
    505
    506    return _ts_or_ds_to_date_sql