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sqlglot/sqlglot/dialects/presto.py
Daniel Baumann 147b6e06e8
Adding upstream version 25.1.0.
Signed-off-by: Daniel Baumann <daniel@debian.org>
2025-02-13 21:38:56 +01:00

649 lines
26 KiB
Python

from __future__ import annotations
import typing as t
from sqlglot import exp, generator, parser, tokens, transforms
from sqlglot.dialects.dialect import (
Dialect,
NormalizationStrategy,
binary_from_function,
bool_xor_sql,
date_trunc_to_time,
datestrtodate_sql,
encode_decode_sql,
build_formatted_time,
if_sql,
left_to_substring_sql,
no_ilike_sql,
no_pivot_sql,
no_safe_divide_sql,
no_timestamp_sql,
regexp_extract_sql,
rename_func,
right_to_substring_sql,
sha256_sql,
struct_extract_sql,
str_position_sql,
timestamptrunc_sql,
timestrtotime_sql,
ts_or_ds_add_cast,
unit_to_str,
)
from sqlglot.dialects.hive import Hive
from sqlglot.dialects.mysql import MySQL
from sqlglot.helper import apply_index_offset, seq_get
from sqlglot.tokens import TokenType
from sqlglot.transforms import unqualify_columns
def _explode_to_unnest_sql(self: Presto.Generator, expression: exp.Lateral) -> str:
if isinstance(expression.this, exp.Explode):
return self.sql(
exp.Join(
this=exp.Unnest(
expressions=[expression.this.this],
alias=expression.args.get("alias"),
offset=isinstance(expression.this, exp.Posexplode),
),
kind="cross",
)
)
return self.lateral_sql(expression)
def _initcap_sql(self: Presto.Generator, expression: exp.Initcap) -> str:
regex = r"(\w)(\w*)"
return f"REGEXP_REPLACE({self.sql(expression, 'this')}, '{regex}', x -> UPPER(x[1]) || LOWER(x[2]))"
def _no_sort_array(self: Presto.Generator, expression: exp.SortArray) -> str:
if expression.args.get("asc") == exp.false():
comparator = "(a, b) -> CASE WHEN a < b THEN 1 WHEN a > b THEN -1 ELSE 0 END"
else:
comparator = None
return self.func("ARRAY_SORT", expression.this, comparator)
def _schema_sql(self: Presto.Generator, expression: exp.Schema) -> str:
if isinstance(expression.parent, exp.Property):
columns = ", ".join(f"'{c.name}'" for c in expression.expressions)
return f"ARRAY[{columns}]"
if expression.parent:
for schema in expression.parent.find_all(exp.Schema):
column_defs = schema.find_all(exp.ColumnDef)
if column_defs and isinstance(schema.parent, exp.Property):
expression.expressions.extend(column_defs)
return self.schema_sql(expression)
def _quantile_sql(self: Presto.Generator, expression: exp.Quantile) -> str:
self.unsupported("Presto does not support exact quantiles")
return self.func("APPROX_PERCENTILE", expression.this, expression.args.get("quantile"))
def _str_to_time_sql(
self: Presto.Generator, expression: exp.StrToDate | exp.StrToTime | exp.TsOrDsToDate
) -> str:
return self.func("DATE_PARSE", expression.this, self.format_time(expression))
def _ts_or_ds_to_date_sql(self: Presto.Generator, expression: exp.TsOrDsToDate) -> str:
time_format = self.format_time(expression)
if time_format and time_format not in (Presto.TIME_FORMAT, Presto.DATE_FORMAT):
return self.sql(exp.cast(_str_to_time_sql(self, expression), exp.DataType.Type.DATE))
return self.sql(
exp.cast(exp.cast(expression.this, exp.DataType.Type.TIMESTAMP), exp.DataType.Type.DATE)
)
def _ts_or_ds_add_sql(self: Presto.Generator, expression: exp.TsOrDsAdd) -> str:
expression = ts_or_ds_add_cast(expression)
unit = unit_to_str(expression)
return self.func("DATE_ADD", unit, expression.expression, expression.this)
def _ts_or_ds_diff_sql(self: Presto.Generator, expression: exp.TsOrDsDiff) -> str:
this = exp.cast(expression.this, exp.DataType.Type.TIMESTAMP)
expr = exp.cast(expression.expression, exp.DataType.Type.TIMESTAMP)
unit = unit_to_str(expression)
return self.func("DATE_DIFF", unit, expr, this)
def _build_approx_percentile(args: t.List) -> exp.Expression:
if len(args) == 4:
return exp.ApproxQuantile(
this=seq_get(args, 0),
weight=seq_get(args, 1),
quantile=seq_get(args, 2),
accuracy=seq_get(args, 3),
)
if len(args) == 3:
return exp.ApproxQuantile(
this=seq_get(args, 0), quantile=seq_get(args, 1), accuracy=seq_get(args, 2)
)
return exp.ApproxQuantile.from_arg_list(args)
def _build_from_unixtime(args: t.List) -> exp.Expression:
if len(args) == 3:
return exp.UnixToTime(
this=seq_get(args, 0),
hours=seq_get(args, 1),
minutes=seq_get(args, 2),
)
if len(args) == 2:
return exp.UnixToTime(this=seq_get(args, 0), zone=seq_get(args, 1))
return exp.UnixToTime.from_arg_list(args)
def _unnest_sequence(expression: exp.Expression) -> exp.Expression:
if isinstance(expression, exp.Table):
if isinstance(expression.this, exp.GenerateSeries):
unnest = exp.Unnest(expressions=[expression.this])
if expression.alias:
return exp.alias_(unnest, alias="_u", table=[expression.alias], copy=False)
return unnest
return expression
def _first_last_sql(self: Presto.Generator, expression: exp.Func) -> str:
"""
Trino doesn't support FIRST / LAST as functions, but they're valid in the context
of MATCH_RECOGNIZE, so we need to preserve them in that case. In all other cases
they're converted into an ARBITRARY call.
Reference: https://trino.io/docs/current/sql/match-recognize.html#logical-navigation-functions
"""
if isinstance(expression.find_ancestor(exp.MatchRecognize, exp.Select), exp.MatchRecognize):
return self.function_fallback_sql(expression)
return rename_func("ARBITRARY")(self, expression)
def _unix_to_time_sql(self: Presto.Generator, expression: exp.UnixToTime) -> str:
scale = expression.args.get("scale")
timestamp = self.sql(expression, "this")
if scale in (None, exp.UnixToTime.SECONDS):
return rename_func("FROM_UNIXTIME")(self, expression)
return f"FROM_UNIXTIME(CAST({timestamp} AS DOUBLE) / POW(10, {scale}))"
def _to_int(expression: exp.Expression) -> exp.Expression:
if not expression.type:
from sqlglot.optimizer.annotate_types import annotate_types
annotate_types(expression)
if expression.type and expression.type.this not in exp.DataType.INTEGER_TYPES:
return exp.cast(expression, to=exp.DataType.Type.BIGINT)
return expression
def _build_to_char(args: t.List) -> exp.TimeToStr:
fmt = seq_get(args, 1)
if isinstance(fmt, exp.Literal):
# We uppercase this to match Teradata's format mapping keys
fmt.set("this", fmt.this.upper())
# We use "teradata" on purpose here, because the time formats are different in Presto.
# See https://prestodb.io/docs/current/functions/teradata.html?highlight=to_char#to_char
return build_formatted_time(exp.TimeToStr, "teradata")(args)
class Presto(Dialect):
INDEX_OFFSET = 1
NULL_ORDERING = "nulls_are_last"
TIME_FORMAT = MySQL.TIME_FORMAT
TIME_MAPPING = MySQL.TIME_MAPPING
STRICT_STRING_CONCAT = True
SUPPORTS_SEMI_ANTI_JOIN = False
TYPED_DIVISION = True
TABLESAMPLE_SIZE_IS_PERCENT = True
LOG_BASE_FIRST: t.Optional[bool] = None
# https://github.com/trinodb/trino/issues/17
# https://github.com/trinodb/trino/issues/12289
# https://github.com/prestodb/presto/issues/2863
NORMALIZATION_STRATEGY = NormalizationStrategy.CASE_INSENSITIVE
class Tokenizer(tokens.Tokenizer):
UNICODE_STRINGS = [
(prefix + q, q)
for q in t.cast(t.List[str], tokens.Tokenizer.QUOTES)
for prefix in ("U&", "u&")
]
KEYWORDS = {
**tokens.Tokenizer.KEYWORDS,
"START": TokenType.BEGIN,
"MATCH_RECOGNIZE": TokenType.MATCH_RECOGNIZE,
"ROW": TokenType.STRUCT,
"IPADDRESS": TokenType.IPADDRESS,
"IPPREFIX": TokenType.IPPREFIX,
"TDIGEST": TokenType.TDIGEST,
"HYPERLOGLOG": TokenType.HLLSKETCH,
}
KEYWORDS.pop("QUALIFY")
class Parser(parser.Parser):
VALUES_FOLLOWED_BY_PAREN = False
FUNCTIONS = {
**parser.Parser.FUNCTIONS,
"ARBITRARY": exp.AnyValue.from_arg_list,
"APPROX_DISTINCT": exp.ApproxDistinct.from_arg_list,
"APPROX_PERCENTILE": _build_approx_percentile,
"BITWISE_AND": binary_from_function(exp.BitwiseAnd),
"BITWISE_NOT": lambda args: exp.BitwiseNot(this=seq_get(args, 0)),
"BITWISE_OR": binary_from_function(exp.BitwiseOr),
"BITWISE_XOR": binary_from_function(exp.BitwiseXor),
"CARDINALITY": exp.ArraySize.from_arg_list,
"CONTAINS": exp.ArrayContains.from_arg_list,
"DATE_ADD": lambda args: exp.DateAdd(
this=seq_get(args, 2), expression=seq_get(args, 1), unit=seq_get(args, 0)
),
"DATE_DIFF": lambda args: exp.DateDiff(
this=seq_get(args, 2), expression=seq_get(args, 1), unit=seq_get(args, 0)
),
"DATE_FORMAT": build_formatted_time(exp.TimeToStr, "presto"),
"DATE_PARSE": build_formatted_time(exp.StrToTime, "presto"),
"DATE_TRUNC": date_trunc_to_time,
"ELEMENT_AT": lambda args: exp.Bracket(
this=seq_get(args, 0), expressions=[seq_get(args, 1)], offset=1, safe=True
),
"FROM_HEX": exp.Unhex.from_arg_list,
"FROM_UNIXTIME": _build_from_unixtime,
"FROM_UTF8": lambda args: exp.Decode(
this=seq_get(args, 0), replace=seq_get(args, 1), charset=exp.Literal.string("utf-8")
),
"NOW": exp.CurrentTimestamp.from_arg_list,
"REGEXP_EXTRACT": lambda args: exp.RegexpExtract(
this=seq_get(args, 0), expression=seq_get(args, 1), group=seq_get(args, 2)
),
"REGEXP_REPLACE": lambda args: exp.RegexpReplace(
this=seq_get(args, 0),
expression=seq_get(args, 1),
replacement=seq_get(args, 2) or exp.Literal.string(""),
),
"ROW": exp.Struct.from_arg_list,
"SEQUENCE": exp.GenerateSeries.from_arg_list,
"SET_AGG": exp.ArrayUniqueAgg.from_arg_list,
"SPLIT_TO_MAP": exp.StrToMap.from_arg_list,
"STRPOS": lambda args: exp.StrPosition(
this=seq_get(args, 0), substr=seq_get(args, 1), instance=seq_get(args, 2)
),
"TO_CHAR": _build_to_char,
"TO_UNIXTIME": exp.TimeToUnix.from_arg_list,
"TO_UTF8": lambda args: exp.Encode(
this=seq_get(args, 0), charset=exp.Literal.string("utf-8")
),
"MD5": exp.MD5Digest.from_arg_list,
"SHA256": lambda args: exp.SHA2(this=seq_get(args, 0), length=exp.Literal.number(256)),
"SHA512": lambda args: exp.SHA2(this=seq_get(args, 0), length=exp.Literal.number(512)),
}
FUNCTION_PARSERS = parser.Parser.FUNCTION_PARSERS.copy()
FUNCTION_PARSERS.pop("TRIM")
class Generator(generator.Generator):
INTERVAL_ALLOWS_PLURAL_FORM = False
JOIN_HINTS = False
TABLE_HINTS = False
QUERY_HINTS = False
IS_BOOL_ALLOWED = False
TZ_TO_WITH_TIME_ZONE = True
NVL2_SUPPORTED = False
STRUCT_DELIMITER = ("(", ")")
LIMIT_ONLY_LITERALS = True
SUPPORTS_SINGLE_ARG_CONCAT = False
LIKE_PROPERTY_INSIDE_SCHEMA = True
MULTI_ARG_DISTINCT = False
SUPPORTS_TO_NUMBER = False
HEX_FUNC = "TO_HEX"
PROPERTIES_LOCATION = {
**generator.Generator.PROPERTIES_LOCATION,
exp.LocationProperty: exp.Properties.Location.UNSUPPORTED,
exp.VolatileProperty: exp.Properties.Location.UNSUPPORTED,
}
TYPE_MAPPING = {
**generator.Generator.TYPE_MAPPING,
exp.DataType.Type.INT: "INTEGER",
exp.DataType.Type.FLOAT: "REAL",
exp.DataType.Type.BINARY: "VARBINARY",
exp.DataType.Type.TEXT: "VARCHAR",
exp.DataType.Type.TIMETZ: "TIME",
exp.DataType.Type.TIMESTAMPTZ: "TIMESTAMP",
exp.DataType.Type.STRUCT: "ROW",
exp.DataType.Type.DATETIME: "TIMESTAMP",
exp.DataType.Type.DATETIME64: "TIMESTAMP",
exp.DataType.Type.HLLSKETCH: "HYPERLOGLOG",
}
TRANSFORMS = {
**generator.Generator.TRANSFORMS,
exp.AnyValue: rename_func("ARBITRARY"),
exp.ApproxDistinct: lambda self, e: self.func(
"APPROX_DISTINCT", e.this, e.args.get("accuracy")
),
exp.ApproxQuantile: rename_func("APPROX_PERCENTILE"),
exp.ArgMax: rename_func("MAX_BY"),
exp.ArgMin: rename_func("MIN_BY"),
exp.Array: lambda self, e: f"ARRAY[{self.expressions(e, flat=True)}]",
exp.ArrayAny: rename_func("ANY_MATCH"),
exp.ArrayConcat: rename_func("CONCAT"),
exp.ArrayContains: rename_func("CONTAINS"),
exp.ArraySize: rename_func("CARDINALITY"),
exp.ArrayToString: rename_func("ARRAY_JOIN"),
exp.ArrayUniqueAgg: rename_func("SET_AGG"),
exp.AtTimeZone: rename_func("AT_TIMEZONE"),
exp.BitwiseAnd: lambda self, e: self.func("BITWISE_AND", e.this, e.expression),
exp.BitwiseLeftShift: lambda self, e: self.func(
"BITWISE_ARITHMETIC_SHIFT_LEFT", e.this, e.expression
),
exp.BitwiseNot: lambda self, e: self.func("BITWISE_NOT", e.this),
exp.BitwiseOr: lambda self, e: self.func("BITWISE_OR", e.this, e.expression),
exp.BitwiseRightShift: lambda self, e: self.func(
"BITWISE_ARITHMETIC_SHIFT_RIGHT", e.this, e.expression
),
exp.BitwiseXor: lambda self, e: self.func("BITWISE_XOR", e.this, e.expression),
exp.Cast: transforms.preprocess([transforms.epoch_cast_to_ts]),
exp.CurrentTimestamp: lambda *_: "CURRENT_TIMESTAMP",
exp.DateAdd: lambda self, e: self.func(
"DATE_ADD",
unit_to_str(e),
_to_int(e.expression),
e.this,
),
exp.DateDiff: lambda self, e: self.func(
"DATE_DIFF", unit_to_str(e), e.expression, e.this
),
exp.DateStrToDate: datestrtodate_sql,
exp.DateToDi: lambda self,
e: f"CAST(DATE_FORMAT({self.sql(e, 'this')}, {Presto.DATEINT_FORMAT}) AS INT)",
exp.DateSub: lambda self, e: self.func(
"DATE_ADD",
unit_to_str(e),
_to_int(e.expression * -1),
e.this,
),
exp.Decode: lambda self, e: encode_decode_sql(self, e, "FROM_UTF8"),
exp.DiToDate: lambda self,
e: f"CAST(DATE_PARSE(CAST({self.sql(e, 'this')} AS VARCHAR), {Presto.DATEINT_FORMAT}) AS DATE)",
exp.Encode: lambda self, e: encode_decode_sql(self, e, "TO_UTF8"),
exp.FileFormatProperty: lambda self, e: f"FORMAT='{e.name.upper()}'",
exp.First: _first_last_sql,
exp.FirstValue: _first_last_sql,
exp.FromTimeZone: lambda self,
e: f"WITH_TIMEZONE({self.sql(e, 'this')}, {self.sql(e, 'zone')}) AT TIME ZONE 'UTC'",
exp.Group: transforms.preprocess([transforms.unalias_group]),
exp.GroupConcat: lambda self, e: self.func(
"ARRAY_JOIN", self.func("ARRAY_AGG", e.this), e.args.get("separator")
),
exp.If: if_sql(),
exp.ILike: no_ilike_sql,
exp.Initcap: _initcap_sql,
exp.ParseJSON: rename_func("JSON_PARSE"),
exp.Last: _first_last_sql,
exp.LastValue: _first_last_sql,
exp.LastDay: lambda self, e: self.func("LAST_DAY_OF_MONTH", e.this),
exp.Lateral: _explode_to_unnest_sql,
exp.Left: left_to_substring_sql,
exp.Levenshtein: rename_func("LEVENSHTEIN_DISTANCE"),
exp.LogicalAnd: rename_func("BOOL_AND"),
exp.LogicalOr: rename_func("BOOL_OR"),
exp.Pivot: no_pivot_sql,
exp.Quantile: _quantile_sql,
exp.RegexpExtract: regexp_extract_sql,
exp.Right: right_to_substring_sql,
exp.SafeDivide: no_safe_divide_sql,
exp.Schema: _schema_sql,
exp.SchemaCommentProperty: lambda self, e: self.naked_property(e),
exp.Select: transforms.preprocess(
[
transforms.eliminate_qualify,
transforms.eliminate_distinct_on,
transforms.explode_to_unnest(1),
transforms.eliminate_semi_and_anti_joins,
]
),
exp.SortArray: _no_sort_array,
exp.StrPosition: lambda self, e: str_position_sql(self, e, generate_instance=True),
exp.StrToDate: lambda self, e: f"CAST({_str_to_time_sql(self, e)} AS DATE)",
exp.StrToMap: rename_func("SPLIT_TO_MAP"),
exp.StrToTime: _str_to_time_sql,
exp.StructExtract: struct_extract_sql,
exp.Table: transforms.preprocess([_unnest_sequence]),
exp.Timestamp: no_timestamp_sql,
exp.TimestampTrunc: timestamptrunc_sql(),
exp.TimeStrToDate: timestrtotime_sql,
exp.TimeStrToTime: timestrtotime_sql,
exp.TimeStrToUnix: lambda self, e: self.func(
"TO_UNIXTIME", self.func("DATE_PARSE", e.this, Presto.TIME_FORMAT)
),
exp.TimeToStr: lambda self, e: self.func("DATE_FORMAT", e.this, self.format_time(e)),
exp.TimeToUnix: rename_func("TO_UNIXTIME"),
exp.ToChar: lambda self, e: self.func("DATE_FORMAT", e.this, self.format_time(e)),
exp.TryCast: transforms.preprocess([transforms.epoch_cast_to_ts]),
exp.TsOrDiToDi: lambda self,
e: f"CAST(SUBSTR(REPLACE(CAST({self.sql(e, 'this')} AS VARCHAR), '-', ''), 1, 8) AS INT)",
exp.TsOrDsAdd: _ts_or_ds_add_sql,
exp.TsOrDsDiff: _ts_or_ds_diff_sql,
exp.TsOrDsToDate: _ts_or_ds_to_date_sql,
exp.Unhex: rename_func("FROM_HEX"),
exp.UnixToStr: lambda self,
e: f"DATE_FORMAT(FROM_UNIXTIME({self.sql(e, 'this')}), {self.format_time(e)})",
exp.UnixToTime: _unix_to_time_sql,
exp.UnixToTimeStr: lambda self,
e: f"CAST(FROM_UNIXTIME({self.sql(e, 'this')}) AS VARCHAR)",
exp.VariancePop: rename_func("VAR_POP"),
exp.With: transforms.preprocess([transforms.add_recursive_cte_column_names]),
exp.WithinGroup: transforms.preprocess(
[transforms.remove_within_group_for_percentiles]
),
exp.Xor: bool_xor_sql,
exp.MD5: lambda self, e: self.func(
"LOWER", self.func("TO_HEX", self.func("MD5", self.sql(e, "this")))
),
exp.MD5Digest: rename_func("MD5"),
exp.SHA: rename_func("SHA1"),
exp.SHA2: sha256_sql,
}
RESERVED_KEYWORDS = {
"alter",
"and",
"as",
"between",
"by",
"case",
"cast",
"constraint",
"create",
"cross",
"current_time",
"current_timestamp",
"deallocate",
"delete",
"describe",
"distinct",
"drop",
"else",
"end",
"escape",
"except",
"execute",
"exists",
"extract",
"false",
"for",
"from",
"full",
"group",
"having",
"in",
"inner",
"insert",
"intersect",
"into",
"is",
"join",
"left",
"like",
"natural",
"not",
"null",
"on",
"or",
"order",
"outer",
"prepare",
"right",
"select",
"table",
"then",
"true",
"union",
"using",
"values",
"when",
"where",
"with",
}
def strtounix_sql(self, expression: exp.StrToUnix) -> str:
# Since `TO_UNIXTIME` requires a `TIMESTAMP`, we need to parse the argument into one.
# To do this, we first try to `DATE_PARSE` it, but since this can fail when there's a
# timezone involved, we wrap it in a `TRY` call and use `PARSE_DATETIME` as a fallback,
# which seems to be using the same time mapping as Hive, as per:
# https://joda-time.sourceforge.net/apidocs/org/joda/time/format/DateTimeFormat.html
value_as_text = exp.cast(expression.this, exp.DataType.Type.TEXT)
parse_without_tz = self.func("DATE_PARSE", value_as_text, self.format_time(expression))
parse_with_tz = self.func(
"PARSE_DATETIME",
value_as_text,
self.format_time(expression, Hive.INVERSE_TIME_MAPPING, Hive.INVERSE_TIME_TRIE),
)
coalesced = self.func("COALESCE", self.func("TRY", parse_without_tz), parse_with_tz)
return self.func("TO_UNIXTIME", coalesced)
def bracket_sql(self, expression: exp.Bracket) -> str:
if expression.args.get("safe"):
return self.func(
"ELEMENT_AT",
expression.this,
seq_get(
apply_index_offset(
expression.this,
expression.expressions,
1 - expression.args.get("offset", 0),
),
0,
),
)
return super().bracket_sql(expression)
def struct_sql(self, expression: exp.Struct) -> str:
from sqlglot.optimizer.annotate_types import annotate_types
expression = annotate_types(expression)
values: t.List[str] = []
schema: t.List[str] = []
unknown_type = False
for e in expression.expressions:
if isinstance(e, exp.PropertyEQ):
if e.type and e.type.is_type(exp.DataType.Type.UNKNOWN):
unknown_type = True
else:
schema.append(f"{self.sql(e, 'this')} {self.sql(e.type)}")
values.append(self.sql(e, "expression"))
else:
values.append(self.sql(e))
size = len(expression.expressions)
if not size or len(schema) != size:
if unknown_type:
self.unsupported(
"Cannot convert untyped key-value definitions (try annotate_types)."
)
return self.func("ROW", *values)
return f"CAST(ROW({', '.join(values)}) AS ROW({', '.join(schema)}))"
def interval_sql(self, expression: exp.Interval) -> str:
if expression.this and expression.text("unit").upper().startswith("WEEK"):
return f"({expression.this.name} * INTERVAL '7' DAY)"
return super().interval_sql(expression)
def transaction_sql(self, expression: exp.Transaction) -> str:
modes = expression.args.get("modes")
modes = f" {', '.join(modes)}" if modes else ""
return f"START TRANSACTION{modes}"
def generateseries_sql(self, expression: exp.GenerateSeries) -> str:
start = expression.args["start"]
end = expression.args["end"]
step = expression.args.get("step")
if isinstance(start, exp.Cast):
target_type = start.to
elif isinstance(end, exp.Cast):
target_type = end.to
else:
target_type = None
if target_type and target_type.is_type("timestamp"):
if target_type is start.to:
end = exp.cast(end, target_type)
else:
start = exp.cast(start, target_type)
return self.func("SEQUENCE", start, end, step)
def offset_limit_modifiers(
self, expression: exp.Expression, fetch: bool, limit: t.Optional[exp.Fetch | exp.Limit]
) -> t.List[str]:
return [
self.sql(expression, "offset"),
self.sql(limit),
]
def create_sql(self, expression: exp.Create) -> str:
"""
Presto doesn't support CREATE VIEW with expressions (ex: `CREATE VIEW x (cola)` then `(cola)` is the expression),
so we need to remove them
"""
kind = expression.args["kind"]
schema = expression.this
if kind == "VIEW" and schema.expressions:
expression.this.set("expressions", None)
return super().create_sql(expression)
def delete_sql(self, expression: exp.Delete) -> str:
"""
Presto only supports DELETE FROM for a single table without an alias, so we need
to remove the unnecessary parts. If the original DELETE statement contains more
than one table to be deleted, we can't safely map it 1-1 to a Presto statement.
"""
tables = expression.args.get("tables") or [expression.this]
if len(tables) > 1:
return super().delete_sql(expression)
table = tables[0]
expression.set("this", table)
expression.set("tables", None)
if isinstance(table, exp.Table):
table_alias = table.args.get("alias")
if table_alias:
table_alias.pop()
expression = t.cast(exp.Delete, expression.transform(unqualify_columns))
return super().delete_sql(expression)