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# sqlglot.dialects.postgres

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      1from __future__ import annotations
      2
      3from sqlglot import exp, generator, parser, tokens, transforms
      4from sqlglot.dialects.dialect import (
      5    Dialect,
      6    arrow_json_extract_scalar_sql,
      7    arrow_json_extract_sql,
      8    datestrtodate_sql,
      9    format_time_lambda,
     10    max_or_greatest,
     11    min_or_least,
     12    no_paren_current_date_sql,
     13    no_tablesample_sql,
     14    no_trycast_sql,
     15    rename_func,
     16    str_position_sql,
     17    timestamptrunc_sql,
     18    trim_sql,
     19)
     20from sqlglot.helper import seq_get
     21from sqlglot.parser import binary_range_parser
     22from sqlglot.tokens import TokenType
     23
     24DATE_DIFF_FACTOR = {
     25    "MICROSECOND": " * 1000000",
     26    "MILLISECOND": " * 1000",
     27    "SECOND": "",
     28    "MINUTE": " / 60",
     29    "HOUR": " / 3600",
     30    "DAY": " / 86400",
     31}
     32
     33
     34def _date_add_sql(kind):
     35    def func(self, expression):
     36        from sqlglot.optimizer.simplify import simplify
     37
     38        this = self.sql(expression, "this")
     39        unit = expression.args.get("unit")
     40        expression = simplify(expression.args["expression"])
     41
     42        if not isinstance(expression, exp.Literal):
     43            self.unsupported("Cannot add non literal")
     44
     45        expression = expression.copy()
     46        expression.args["is_string"] = True
     47        return f"{this} {kind} {self.sql(exp.Interval(this=expression, unit=unit))}"
     48
     49    return func
     50
     51
     52def _date_diff_sql(self, expression):
     53    unit = expression.text("unit").upper()
     54    factor = DATE_DIFF_FACTOR.get(unit)
     55
     56    end = f"CAST({expression.this} AS TIMESTAMP)"
     57    start = f"CAST({expression.expression} AS TIMESTAMP)"
     58
     59    if factor is not None:
     60        return f"CAST(EXTRACT(epoch FROM {end} - {start}){factor} AS BIGINT)"
     61
     62    age = f"AGE({end}, {start})"
     63
     64    if unit == "WEEK":
     65        unit = f"EXTRACT(year FROM {age}) * 48 + EXTRACT(month FROM {age}) * 4 + EXTRACT(day FROM {age}) / 7"
     66    elif unit == "MONTH":
     67        unit = f"EXTRACT(year FROM {age}) * 12 + EXTRACT(month FROM {age})"
     68    elif unit == "QUARTER":
     69        unit = f"EXTRACT(year FROM {age}) * 4 + EXTRACT(month FROM {age}) / 3"
     70    elif unit == "YEAR":
     71        unit = f"EXTRACT(year FROM {age})"
     72    else:
     73        unit = age
     74
     75    return f"CAST({unit} AS BIGINT)"
     76
     77
     78def _substring_sql(self, expression):
     79    this = self.sql(expression, "this")
     80    start = self.sql(expression, "start")
     81    length = self.sql(expression, "length")
     82
     83    from_part = f" FROM {start}" if start else ""
     84    for_part = f" FOR {length}" if length else ""
     85
     86    return f"SUBSTRING({this}{from_part}{for_part})"
     87
     88
     89def _string_agg_sql(self, expression):
     90    expression = expression.copy()
     91    separator = expression.args.get("separator") or exp.Literal.string(",")
     92
     93    order = ""
     94    this = expression.this
     95    if isinstance(this, exp.Order):
     96        if this.this:
     97            this = this.this.pop()
     98        order = self.sql(expression.this)  # Order has a leading space
     99
    100    return f"STRING_AGG({self.format_args(this, separator)}{order})"
    101
    102
    103def _datatype_sql(self, expression):
    104    if expression.this == exp.DataType.Type.ARRAY:
    105        return f"{self.expressions(expression, flat=True)}[]"
    106    return self.datatype_sql(expression)
    107
    108
    109def _auto_increment_to_serial(expression):
    110    auto = expression.find(exp.AutoIncrementColumnConstraint)
    111
    112    if auto:
    113        expression = expression.copy()
    114        expression.args["constraints"].remove(auto.parent)
    115        kind = expression.args["kind"]
    116
    117        if kind.this == exp.DataType.Type.INT:
    118            kind.replace(exp.DataType(this=exp.DataType.Type.SERIAL))
    119        elif kind.this == exp.DataType.Type.SMALLINT:
    120            kind.replace(exp.DataType(this=exp.DataType.Type.SMALLSERIAL))
    121        elif kind.this == exp.DataType.Type.BIGINT:
    122            kind.replace(exp.DataType(this=exp.DataType.Type.BIGSERIAL))
    123
    124    return expression
    125
    126
    127def _serial_to_generated(expression):
    128    kind = expression.args["kind"]
    129
    130    if kind.this == exp.DataType.Type.SERIAL:
    131        data_type = exp.DataType(this=exp.DataType.Type.INT)
    132    elif kind.this == exp.DataType.Type.SMALLSERIAL:
    133        data_type = exp.DataType(this=exp.DataType.Type.SMALLINT)
    134    elif kind.this == exp.DataType.Type.BIGSERIAL:
    135        data_type = exp.DataType(this=exp.DataType.Type.BIGINT)
    136    else:
    137        data_type = None
    138
    139    if data_type:
    140        expression = expression.copy()
    141        expression.args["kind"].replace(data_type)
    142        constraints = expression.args["constraints"]
    143        generated = exp.ColumnConstraint(kind=exp.GeneratedAsIdentityColumnConstraint(this=False))
    144        notnull = exp.ColumnConstraint(kind=exp.NotNullColumnConstraint())
    145        if notnull not in constraints:
    146            constraints.insert(0, notnull)
    147        if generated not in constraints:
    148            constraints.insert(0, generated)
    149
    150    return expression
    151
    152
    153def _generate_series(args):
    154    # The goal is to convert step values like '1 day' or INTERVAL '1 day' into INTERVAL '1' day
    155    step = seq_get(args, 2)
    156
    157    if step is None:
    158        # Postgres allows calls with just two arguments -- the "step" argument defaults to 1
    159        return exp.GenerateSeries.from_arg_list(args)
    160
    161    if step.is_string:
    162        args[2] = exp.to_interval(step.this)
    163    elif isinstance(step, exp.Interval) and not step.args.get("unit"):
    164        args[2] = exp.to_interval(step.this.this)
    165
    166    return exp.GenerateSeries.from_arg_list(args)
    167
    168
    169def _to_timestamp(args):
    170    # TO_TIMESTAMP accepts either a single double argument or (text, text)
    171    if len(args) == 1:
    172        # https://www.postgresql.org/docs/current/functions-datetime.html#FUNCTIONS-DATETIME-TABLE
    173        return exp.UnixToTime.from_arg_list(args)
    174    # https://www.postgresql.org/docs/current/functions-formatting.html
    175    return format_time_lambda(exp.StrToTime, "postgres")(args)
    176
    177
    178class Postgres(Dialect):
    179    null_ordering = "nulls_are_large"
    180    time_format = "'YYYY-MM-DD HH24:MI:SS'"
    181    time_mapping = {
    182        "AM": "%p",
    183        "PM": "%p",
    184        "D": "%u",  # 1-based day of week
    185        "DD": "%d",  # day of month
    186        "DDD": "%j",  # zero padded day of year
    187        "FMDD": "%-d",  # - is no leading zero for Python; same for FM in postgres
    188        "FMDDD": "%-j",  # day of year
    189        "FMHH12": "%-I",  # 9
    190        "FMHH24": "%-H",  # 9
    191        "FMMI": "%-M",  # Minute
    192        "FMMM": "%-m",  # 1
    193        "FMSS": "%-S",  # Second
    194        "HH12": "%I",  # 09
    195        "HH24": "%H",  # 09
    196        "MI": "%M",  # zero padded minute
    197        "MM": "%m",  # 01
    198        "OF": "%z",  # utc offset
    199        "SS": "%S",  # zero padded second
    200        "TMDay": "%A",  # TM is locale dependent
    201        "TMDy": "%a",
    202        "TMMon": "%b",  # Sep
    203        "TMMonth": "%B",  # September
    204        "TZ": "%Z",  # uppercase timezone name
    205        "US": "%f",  # zero padded microsecond
    206        "WW": "%U",  # 1-based week of year
    207        "YY": "%y",  # 15
    208        "YYYY": "%Y",  # 2015
    209    }
    210
    211    class Tokenizer(tokens.Tokenizer):
    212        QUOTES = ["'", "$$"]
    213
    214        BIT_STRINGS = [("b'", "'"), ("B'", "'")]
    215        HEX_STRINGS = [("x'", "'"), ("X'", "'")]
    216        BYTE_STRINGS = [("e'", "'"), ("E'", "'")]
    217
    218        KEYWORDS = {
    219            **tokens.Tokenizer.KEYWORDS,
    220            "~~": TokenType.LIKE,
    221            "~~*": TokenType.ILIKE,
    222            "~*": TokenType.IRLIKE,
    223            "~": TokenType.RLIKE,
    224            "@>": TokenType.AT_GT,
    225            "<@": TokenType.LT_AT,
    226            "BEGIN": TokenType.COMMAND,
    227            "BEGIN TRANSACTION": TokenType.BEGIN,
    228            "BIGSERIAL": TokenType.BIGSERIAL,
    229            "CHARACTER VARYING": TokenType.VARCHAR,
    230            "DECLARE": TokenType.COMMAND,
    231            "DO": TokenType.COMMAND,
    232            "HSTORE": TokenType.HSTORE,
    233            "JSONB": TokenType.JSONB,
    234            "REFRESH": TokenType.COMMAND,
    235            "REINDEX": TokenType.COMMAND,
    236            "RESET": TokenType.COMMAND,
    237            "RETURNING": TokenType.RETURNING,
    238            "REVOKE": TokenType.COMMAND,
    239            "SERIAL": TokenType.SERIAL,
    240            "SMALLSERIAL": TokenType.SMALLSERIAL,
    241            "TEMP": TokenType.TEMPORARY,
    242            "CSTRING": TokenType.PSEUDO_TYPE,
    243        }
    244
    245        SINGLE_TOKENS = {
    246            **tokens.Tokenizer.SINGLE_TOKENS,
    247            "$": TokenType.PARAMETER,
    248        }
    249
    250        VAR_SINGLE_TOKENS = {"$"}
    251
    252    class Parser(parser.Parser):
    253        STRICT_CAST = False
    254
    255        FUNCTIONS = {
    256            **parser.Parser.FUNCTIONS,  # type: ignore
    257            "DATE_TRUNC": lambda args: exp.TimestampTrunc(
    258                this=seq_get(args, 1), unit=seq_get(args, 0)
    259            ),
    260            "GENERATE_SERIES": _generate_series,
    261            "NOW": exp.CurrentTimestamp.from_arg_list,
    262            "TO_CHAR": format_time_lambda(exp.TimeToStr, "postgres"),
    263            "TO_TIMESTAMP": _to_timestamp,
    264        }
    265
    266        FUNCTION_PARSERS = {
    267            **parser.Parser.FUNCTION_PARSERS,
    268            "DATE_PART": lambda self: self._parse_date_part(),
    269        }
    270
    271        BITWISE = {
    272            **parser.Parser.BITWISE,  # type: ignore
    273            TokenType.HASH: exp.BitwiseXor,
    274        }
    275
    276        FACTOR = {
    277            **parser.Parser.FACTOR,
    278            TokenType.CARET: exp.Pow,
    279        }
    280
    281        RANGE_PARSERS = {
    282            **parser.Parser.RANGE_PARSERS,  # type: ignore
    283            TokenType.DAMP: binary_range_parser(exp.ArrayOverlaps),
    284            TokenType.AT_GT: binary_range_parser(exp.ArrayContains),
    285            TokenType.LT_AT: binary_range_parser(exp.ArrayContained),
    286        }
    287
    288        def _parse_date_part(self) -> exp.Expression:
    289            part = self._parse_type()
    290            self._match(TokenType.COMMA)
    291            value = self._parse_bitwise()
    292
    293            if part and part.is_string:
    294                part = exp.Var(this=part.name)
    295
    296            return self.expression(exp.Extract, this=part, expression=value)
    297
    298    class Generator(generator.Generator):
    299        INTERVAL_ALLOWS_PLURAL_FORM = False
    300        LOCKING_READS_SUPPORTED = True
    301        JOIN_HINTS = False
    302        TABLE_HINTS = False
    303        PARAMETER_TOKEN = "$"
    304
    305        TYPE_MAPPING = {
    306            **generator.Generator.TYPE_MAPPING,  # type: ignore
    307            exp.DataType.Type.TINYINT: "SMALLINT",
    308            exp.DataType.Type.FLOAT: "REAL",
    309            exp.DataType.Type.DOUBLE: "DOUBLE PRECISION",
    310            exp.DataType.Type.BINARY: "BYTEA",
    311            exp.DataType.Type.VARBINARY: "BYTEA",
    312            exp.DataType.Type.DATETIME: "TIMESTAMP",
    313        }
    314
    315        TRANSFORMS = {
    316            **generator.Generator.TRANSFORMS,  # type: ignore
    317            exp.BitwiseXor: lambda self, e: self.binary(e, "#"),
    318            exp.ColumnDef: transforms.preprocess(
    319                [
    320                    _auto_increment_to_serial,
    321                    _serial_to_generated,
    322                ],
    323            ),
    324            exp.JSONExtract: arrow_json_extract_sql,
    325            exp.JSONExtractScalar: arrow_json_extract_scalar_sql,
    326            exp.JSONBExtract: lambda self, e: self.binary(e, "#>"),
    327            exp.JSONBExtractScalar: lambda self, e: self.binary(e, "#>>"),
    328            exp.JSONBContains: lambda self, e: self.binary(e, "?"),
    329            exp.Pow: lambda self, e: self.binary(e, "^"),
    330            exp.CurrentDate: no_paren_current_date_sql,
    331            exp.CurrentTimestamp: lambda *_: "CURRENT_TIMESTAMP",
    332            exp.DateAdd: _date_add_sql("+"),
    333            exp.DateStrToDate: datestrtodate_sql,
    334            exp.DateSub: _date_add_sql("-"),
    335            exp.DateDiff: _date_diff_sql,
    336            exp.LogicalOr: rename_func("BOOL_OR"),
    337            exp.LogicalAnd: rename_func("BOOL_AND"),
    338            exp.Max: max_or_greatest,
    339            exp.Min: min_or_least,
    340            exp.ArrayOverlaps: lambda self, e: self.binary(e, "&&"),
    341            exp.ArrayContains: lambda self, e: self.binary(e, "@>"),
    342            exp.ArrayContained: lambda self, e: self.binary(e, "<@"),
    343            exp.Merge: transforms.preprocess([transforms.remove_target_from_merge]),
    344            exp.RegexpLike: lambda self, e: self.binary(e, "~"),
    345            exp.RegexpILike: lambda self, e: self.binary(e, "~*"),
    346            exp.StrPosition: str_position_sql,
    347            exp.StrToTime: lambda self, e: f"TO_TIMESTAMP({self.sql(e, 'this')}, {self.format_time(e)})",
    348            exp.Substring: _substring_sql,
    349            exp.TimestampTrunc: timestamptrunc_sql,
    350            exp.TimeStrToTime: lambda self, e: f"CAST({self.sql(e, 'this')} AS TIMESTAMP)",
    351            exp.TimeToStr: lambda self, e: f"TO_CHAR({self.sql(e, 'this')}, {self.format_time(e)})",
    352            exp.TableSample: no_tablesample_sql,
    353            exp.ToChar: lambda self, e: self.function_fallback_sql(e),
    354            exp.Trim: trim_sql,
    355            exp.TryCast: no_trycast_sql,
    356            exp.UnixToTime: lambda self, e: f"TO_TIMESTAMP({self.sql(e, 'this')})",
    357            exp.DataType: _datatype_sql,
    358            exp.GroupConcat: _string_agg_sql,
    359            exp.Array: lambda self, e: f"{self.normalize_func('ARRAY')}({self.sql(e.expressions[0])})"
    360            if isinstance(seq_get(e.expressions, 0), exp.Select)
    361            else f"{self.normalize_func('ARRAY')}[{self.expressions(e, flat=True)}]",
    362        }
    363
    364        PROPERTIES_LOCATION = {
    365            **generator.Generator.PROPERTIES_LOCATION,  # type: ignore
    366            exp.TransientProperty: exp.Properties.Location.UNSUPPORTED,
    367            exp.VolatileProperty: exp.Properties.Location.UNSUPPORTED,
    368        }

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

    179class Postgres(Dialect):
    180    null_ordering = "nulls_are_large"
    181    time_format = "'YYYY-MM-DD HH24:MI:SS'"
    182    time_mapping = {
    183        "AM": "%p",
    184        "PM": "%p",
    185        "D": "%u",  # 1-based day of week
    186        "DD": "%d",  # day of month
    187        "DDD": "%j",  # zero padded day of year
    188        "FMDD": "%-d",  # - is no leading zero for Python; same for FM in postgres
    189        "FMDDD": "%-j",  # day of year
    190        "FMHH12": "%-I",  # 9
    191        "FMHH24": "%-H",  # 9
    192        "FMMI": "%-M",  # Minute
    193        "FMMM": "%-m",  # 1
    194        "FMSS": "%-S",  # Second
    195        "HH12": "%I",  # 09
    196        "HH24": "%H",  # 09
    197        "MI": "%M",  # zero padded minute
    198        "MM": "%m",  # 01
    199        "OF": "%z",  # utc offset
    200        "SS": "%S",  # zero padded second
    201        "TMDay": "%A",  # TM is locale dependent
    202        "TMDy": "%a",
    203        "TMMon": "%b",  # Sep
    204        "TMMonth": "%B",  # September
    205        "TZ": "%Z",  # uppercase timezone name
    206        "US": "%f",  # zero padded microsecond
    207        "WW": "%U",  # 1-based week of year
    208        "YY": "%y",  # 15
    209        "YYYY": "%Y",  # 2015
    210    }
    211
    212    class Tokenizer(tokens.Tokenizer):
    213        QUOTES = ["'", "$$"]
    214
    215        BIT_STRINGS = [("b'", "'"), ("B'", "'")]
    216        HEX_STRINGS = [("x'", "'"), ("X'", "'")]
    217        BYTE_STRINGS = [("e'", "'"), ("E'", "'")]
    218
    219        KEYWORDS = {
    220            **tokens.Tokenizer.KEYWORDS,
    221            "~~": TokenType.LIKE,
    222            "~~*": TokenType.ILIKE,
    223            "~*": TokenType.IRLIKE,
    224            "~": TokenType.RLIKE,
    225            "@>": TokenType.AT_GT,
    226            "<@": TokenType.LT_AT,
    227            "BEGIN": TokenType.COMMAND,
    228            "BEGIN TRANSACTION": TokenType.BEGIN,
    229            "BIGSERIAL": TokenType.BIGSERIAL,
    230            "CHARACTER VARYING": TokenType.VARCHAR,
    231            "DECLARE": TokenType.COMMAND,
    232            "DO": TokenType.COMMAND,
    233            "HSTORE": TokenType.HSTORE,
    234            "JSONB": TokenType.JSONB,
    235            "REFRESH": TokenType.COMMAND,
    236            "REINDEX": TokenType.COMMAND,
    237            "RESET": TokenType.COMMAND,
    238            "RETURNING": TokenType.RETURNING,
    239            "REVOKE": TokenType.COMMAND,
    240            "SERIAL": TokenType.SERIAL,
    241            "SMALLSERIAL": TokenType.SMALLSERIAL,
    242            "TEMP": TokenType.TEMPORARY,
    243            "CSTRING": TokenType.PSEUDO_TYPE,
    244        }
    245
    246        SINGLE_TOKENS = {
    247            **tokens.Tokenizer.SINGLE_TOKENS,
    248            "$": TokenType.PARAMETER,
    249        }
    250
    251        VAR_SINGLE_TOKENS = {"$"}
    252
    253    class Parser(parser.Parser):
    254        STRICT_CAST = False
    255
    256        FUNCTIONS = {
    257            **parser.Parser.FUNCTIONS,  # type: ignore
    258            "DATE_TRUNC": lambda args: exp.TimestampTrunc(
    259                this=seq_get(args, 1), unit=seq_get(args, 0)
    260            ),
    261            "GENERATE_SERIES": _generate_series,
    262            "NOW": exp.CurrentTimestamp.from_arg_list,
    263            "TO_CHAR": format_time_lambda(exp.TimeToStr, "postgres"),
    264            "TO_TIMESTAMP": _to_timestamp,
    265        }
    266
    267        FUNCTION_PARSERS = {
    268            **parser.Parser.FUNCTION_PARSERS,
    269            "DATE_PART": lambda self: self._parse_date_part(),
    270        }
    271
    272        BITWISE = {
    273            **parser.Parser.BITWISE,  # type: ignore
    274            TokenType.HASH: exp.BitwiseXor,
    275        }
    276
    277        FACTOR = {
    278            **parser.Parser.FACTOR,
    279            TokenType.CARET: exp.Pow,
    280        }
    281
    282        RANGE_PARSERS = {
    283            **parser.Parser.RANGE_PARSERS,  # type: ignore
    284            TokenType.DAMP: binary_range_parser(exp.ArrayOverlaps),
    285            TokenType.AT_GT: binary_range_parser(exp.ArrayContains),
    286            TokenType.LT_AT: binary_range_parser(exp.ArrayContained),
    287        }
    288
    289        def _parse_date_part(self) -> exp.Expression:
    290            part = self._parse_type()
    291            self._match(TokenType.COMMA)
    292            value = self._parse_bitwise()
    293
    294            if part and part.is_string:
    295                part = exp.Var(this=part.name)
    296
    297            return self.expression(exp.Extract, this=part, expression=value)
    298
    299    class Generator(generator.Generator):
    300        INTERVAL_ALLOWS_PLURAL_FORM = False
    301        LOCKING_READS_SUPPORTED = True
    302        JOIN_HINTS = False
    303        TABLE_HINTS = False
    304        PARAMETER_TOKEN = "$"
    305
    306        TYPE_MAPPING = {
    307            **generator.Generator.TYPE_MAPPING,  # type: ignore
    308            exp.DataType.Type.TINYINT: "SMALLINT",
    309            exp.DataType.Type.FLOAT: "REAL",
    310            exp.DataType.Type.DOUBLE: "DOUBLE PRECISION",
    311            exp.DataType.Type.BINARY: "BYTEA",
    312            exp.DataType.Type.VARBINARY: "BYTEA",
    313            exp.DataType.Type.DATETIME: "TIMESTAMP",
    314        }
    315
    316        TRANSFORMS = {
    317            **generator.Generator.TRANSFORMS,  # type: ignore
    318            exp.BitwiseXor: lambda self, e: self.binary(e, "#"),
    319            exp.ColumnDef: transforms.preprocess(
    320                [
    321                    _auto_increment_to_serial,
    322                    _serial_to_generated,
    323                ],
    324            ),
    325            exp.JSONExtract: arrow_json_extract_sql,
    326            exp.JSONExtractScalar: arrow_json_extract_scalar_sql,
    327            exp.JSONBExtract: lambda self, e: self.binary(e, "#>"),
    328            exp.JSONBExtractScalar: lambda self, e: self.binary(e, "#>>"),
    329            exp.JSONBContains: lambda self, e: self.binary(e, "?"),
    330            exp.Pow: lambda self, e: self.binary(e, "^"),
    331            exp.CurrentDate: no_paren_current_date_sql,
    332            exp.CurrentTimestamp: lambda *_: "CURRENT_TIMESTAMP",
    333            exp.DateAdd: _date_add_sql("+"),
    334            exp.DateStrToDate: datestrtodate_sql,
    335            exp.DateSub: _date_add_sql("-"),
    336            exp.DateDiff: _date_diff_sql,
    337            exp.LogicalOr: rename_func("BOOL_OR"),
    338            exp.LogicalAnd: rename_func("BOOL_AND"),
    339            exp.Max: max_or_greatest,
    340            exp.Min: min_or_least,
    341            exp.ArrayOverlaps: lambda self, e: self.binary(e, "&&"),
    342            exp.ArrayContains: lambda self, e: self.binary(e, "@>"),
    343            exp.ArrayContained: lambda self, e: self.binary(e, "<@"),
    344            exp.Merge: transforms.preprocess([transforms.remove_target_from_merge]),
    345            exp.RegexpLike: lambda self, e: self.binary(e, "~"),
    346            exp.RegexpILike: lambda self, e: self.binary(e, "~*"),
    347            exp.StrPosition: str_position_sql,
    348            exp.StrToTime: lambda self, e: f"TO_TIMESTAMP({self.sql(e, 'this')}, {self.format_time(e)})",
    349            exp.Substring: _substring_sql,
    350            exp.TimestampTrunc: timestamptrunc_sql,
    351            exp.TimeStrToTime: lambda self, e: f"CAST({self.sql(e, 'this')} AS TIMESTAMP)",
    352            exp.TimeToStr: lambda self, e: f"TO_CHAR({self.sql(e, 'this')}, {self.format_time(e)})",
    353            exp.TableSample: no_tablesample_sql,
    354            exp.ToChar: lambda self, e: self.function_fallback_sql(e),
    355            exp.Trim: trim_sql,
    356            exp.TryCast: no_trycast_sql,
    357            exp.UnixToTime: lambda self, e: f"TO_TIMESTAMP({self.sql(e, 'this')})",
    358            exp.DataType: _datatype_sql,
    359            exp.GroupConcat: _string_agg_sql,
    360            exp.Array: lambda self, e: f"{self.normalize_func('ARRAY')}({self.sql(e.expressions[0])})"
    361            if isinstance(seq_get(e.expressions, 0), exp.Select)
    362            else f"{self.normalize_func('ARRAY')}[{self.expressions(e, flat=True)}]",
    363        }
    364
    365        PROPERTIES_LOCATION = {
    366            **generator.Generator.PROPERTIES_LOCATION,  # type: ignore
    367            exp.TransientProperty: exp.Properties.Location.UNSUPPORTED,
    368            exp.VolatileProperty: exp.Properties.Location.UNSUPPORTED,
    369        }

##### Inherited Members

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

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

    212    class Tokenizer(tokens.Tokenizer):
    213        QUOTES = ["'", "$$"]
    214
    215        BIT_STRINGS = [("b'", "'"), ("B'", "'")]
    216        HEX_STRINGS = [("x'", "'"), ("X'", "'")]
    217        BYTE_STRINGS = [("e'", "'"), ("E'", "'")]
    218
    219        KEYWORDS = {
    220            **tokens.Tokenizer.KEYWORDS,
    221            "~~": TokenType.LIKE,
    222            "~~*": TokenType.ILIKE,
    223            "~*": TokenType.IRLIKE,
    224            "~": TokenType.RLIKE,
    225            "@>": TokenType.AT_GT,
    226            "<@": TokenType.LT_AT,
    227            "BEGIN": TokenType.COMMAND,
    228            "BEGIN TRANSACTION": TokenType.BEGIN,
    229            "BIGSERIAL": TokenType.BIGSERIAL,
    230            "CHARACTER VARYING": TokenType.VARCHAR,
    231            "DECLARE": TokenType.COMMAND,
    232            "DO": TokenType.COMMAND,
    233            "HSTORE": TokenType.HSTORE,
    234            "JSONB": TokenType.JSONB,
    235            "REFRESH": TokenType.COMMAND,
    236            "REINDEX": TokenType.COMMAND,
    237            "RESET": TokenType.COMMAND,
    238            "RETURNING": TokenType.RETURNING,
    239            "REVOKE": TokenType.COMMAND,
    240            "SERIAL": TokenType.SERIAL,
    241            "SMALLSERIAL": TokenType.SMALLSERIAL,
    242            "TEMP": TokenType.TEMPORARY,
    243            "CSTRING": TokenType.PSEUDO_TYPE,
    244        }
    245
    246        SINGLE_TOKENS = {
    247            **tokens.Tokenizer.SINGLE_TOKENS,
    248            "$": TokenType.PARAMETER,
    249        }
    250
    251        VAR_SINGLE_TOKENS = {"$"}

##### Inherited Members

sqlglot.tokens.Tokenizer
  reset
  tokenize

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

    253    class Parser(parser.Parser):
    254        STRICT_CAST = False
    255
    256        FUNCTIONS = {
    257            **parser.Parser.FUNCTIONS,  # type: ignore
    258            "DATE_TRUNC": lambda args: exp.TimestampTrunc(
    259                this=seq_get(args, 1), unit=seq_get(args, 0)
    260            ),
    261            "GENERATE_SERIES": _generate_series,
    262            "NOW": exp.CurrentTimestamp.from_arg_list,
    263            "TO_CHAR": format_time_lambda(exp.TimeToStr, "postgres"),
    264            "TO_TIMESTAMP": _to_timestamp,
    265        }
    266
    267        FUNCTION_PARSERS = {
    268            **parser.Parser.FUNCTION_PARSERS,
    269            "DATE_PART": lambda self: self._parse_date_part(),
    270        }
    271
    272        BITWISE = {
    273            **parser.Parser.BITWISE,  # type: ignore
    274            TokenType.HASH: exp.BitwiseXor,
    275        }
    276
    277        FACTOR = {
    278            **parser.Parser.FACTOR,
    279            TokenType.CARET: exp.Pow,
    280        }
    281
    282        RANGE_PARSERS = {
    283            **parser.Parser.RANGE_PARSERS,  # type: ignore
    284            TokenType.DAMP: binary_range_parser(exp.ArrayOverlaps),
    285            TokenType.AT_GT: binary_range_parser(exp.ArrayContains),
    286            TokenType.LT_AT: binary_range_parser(exp.ArrayContained),
    287        }
    288
    289        def _parse_date_part(self) -> exp.Expression:
    290            part = self._parse_type()
    291            self._match(TokenType.COMMA)
    292            value = self._parse_bitwise()
    293
    294            if part and part.is_string:
    295                part = exp.Var(this=part.name)
    296
    297            return self.expression(exp.Extract, this=part, expression=value)

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 Postgres.Generator(sqlglot.generator.Generator): View Source

    299    class Generator(generator.Generator):
    300        INTERVAL_ALLOWS_PLURAL_FORM = False
    301        LOCKING_READS_SUPPORTED = True
    302        JOIN_HINTS = False
    303        TABLE_HINTS = False
    304        PARAMETER_TOKEN = "$"
    305
    306        TYPE_MAPPING = {
    307            **generator.Generator.TYPE_MAPPING,  # type: ignore
    308            exp.DataType.Type.TINYINT: "SMALLINT",
    309            exp.DataType.Type.FLOAT: "REAL",
    310            exp.DataType.Type.DOUBLE: "DOUBLE PRECISION",
    311            exp.DataType.Type.BINARY: "BYTEA",
    312            exp.DataType.Type.VARBINARY: "BYTEA",
    313            exp.DataType.Type.DATETIME: "TIMESTAMP",
    314        }
    315
    316        TRANSFORMS = {
    317            **generator.Generator.TRANSFORMS,  # type: ignore
    318            exp.BitwiseXor: lambda self, e: self.binary(e, "#"),
    319            exp.ColumnDef: transforms.preprocess(
    320                [
    321                    _auto_increment_to_serial,
    322                    _serial_to_generated,
    323                ],
    324            ),
    325            exp.JSONExtract: arrow_json_extract_sql,
    326            exp.JSONExtractScalar: arrow_json_extract_scalar_sql,
    327            exp.JSONBExtract: lambda self, e: self.binary(e, "#>"),
    328            exp.JSONBExtractScalar: lambda self, e: self.binary(e, "#>>"),
    329            exp.JSONBContains: lambda self, e: self.binary(e, "?"),
    330            exp.Pow: lambda self, e: self.binary(e, "^"),
    331            exp.CurrentDate: no_paren_current_date_sql,
    332            exp.CurrentTimestamp: lambda *_: "CURRENT_TIMESTAMP",
    333            exp.DateAdd: _date_add_sql("+"),
    334            exp.DateStrToDate: datestrtodate_sql,
    335            exp.DateSub: _date_add_sql("-"),
    336            exp.DateDiff: _date_diff_sql,
    337            exp.LogicalOr: rename_func("BOOL_OR"),
    338            exp.LogicalAnd: rename_func("BOOL_AND"),
    339            exp.Max: max_or_greatest,
    340            exp.Min: min_or_least,
    341            exp.ArrayOverlaps: lambda self, e: self.binary(e, "&&"),
    342            exp.ArrayContains: lambda self, e: self.binary(e, "@>"),
    343            exp.ArrayContained: lambda self, e: self.binary(e, "<@"),
    344            exp.Merge: transforms.preprocess([transforms.remove_target_from_merge]),
    345            exp.RegexpLike: lambda self, e: self.binary(e, "~"),
    346            exp.RegexpILike: lambda self, e: self.binary(e, "~*"),
    347            exp.StrPosition: str_position_sql,
    348            exp.StrToTime: lambda self, e: f"TO_TIMESTAMP({self.sql(e, 'this')}, {self.format_time(e)})",
    349            exp.Substring: _substring_sql,
    350            exp.TimestampTrunc: timestamptrunc_sql,
    351            exp.TimeStrToTime: lambda self, e: f"CAST({self.sql(e, 'this')} AS TIMESTAMP)",
    352            exp.TimeToStr: lambda self, e: f"TO_CHAR({self.sql(e, 'this')}, {self.format_time(e)})",
    353            exp.TableSample: no_tablesample_sql,
    354            exp.ToChar: lambda self, e: self.function_fallback_sql(e),
    355            exp.Trim: trim_sql,
    356            exp.TryCast: no_trycast_sql,
    357            exp.UnixToTime: lambda self, e: f"TO_TIMESTAMP({self.sql(e, 'this')})",
    358            exp.DataType: _datatype_sql,
    359            exp.GroupConcat: _string_agg_sql,
    360            exp.Array: lambda self, e: f"{self.normalize_func('ARRAY')}({self.sql(e.expressions[0])})"
    361            if isinstance(seq_get(e.expressions, 0), exp.Select)
    362            else f"{self.normalize_func('ARRAY')}[{self.expressions(e, flat=True)}]",
    363        }
    364
    365        PROPERTIES_LOCATION = {
    366            **generator.Generator.PROPERTIES_LOCATION,  # type: ignore
    367            exp.TransientProperty: exp.Properties.Location.UNSUPPORTED,
    368            exp.VolatileProperty: exp.Properties.Location.UNSUPPORTED,
    369        }

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 | str): 'always': always quote, 'safe': quote identifiers if they don't contain an upcase, True defaults to always.
- 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

##### 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
  columnposition_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
  cte_sql
  tablealias_sql
  bitstring_sql
  hexstring_sql
  bytestring_sql
  datatype_sql
  directory_sql
  delete_sql
  drop_sql
  except_sql
  except_op
  fetch_sql
  filter_sql
  hint_sql
  index_sql
  identifier_sql
  inputoutputformat_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
  onconflict_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
  setitem_sql
  set_sql
  pragma_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
  windowspec_sql
  withingroup_sql
  between_sql
  bracket_sql
  all_sql
  any_sql
  exists_sql
  case_sql
  constraint_sql
  nextvaluefor_sql
  extract_sql
  trim_sql
  concat_sql
  check_sql
  foreignkey_sql
  primarykey_sql
  unique_sql
  if_sql
  matchagainst_sql
  jsonkeyvalue_sql
  jsonobject_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
  overlaps_sql
  distance_sql
  dot_sql
  eq_sql
  escape_sql
  glob_sql
  gt_sql
  gte_sql
  ilike_sql
  ilikeany_sql
  is_sql
  like_sql
  likeany_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
  tochar_sql