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Adding upstream version 15.0.0.

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Signed-off-by: Daniel Baumann <daniel@debian.org>
This commit is contained in:
Daniel Baumann 2025-02-13 15:56:32 +01:00
parent 70d5d3451a
commit bb75596aa9
Signed by: daniel
GPG key ID: FBB4F0E80A80222F
167 changed files with 58268 additions and 51337 deletions
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45
sqlglot/optimizer/qualify_tables.py
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@ -1,11 +1,19 @@
import itertools
import typing as t
from sqlglot import alias, exp
from sqlglot.helper import csv_reader
from sqlglot._typing import E
from sqlglot.helper import csv_reader, name_sequence
from sqlglot.optimizer.scope import Scope, traverse_scope
from sqlglot.schema import Schema
def qualify_tables(expression, db=None, catalog=None, schema=None):
def qualify_tables(
expression: E,
db: t.Optional[str] = None,
catalog: t.Optional[str] = None,
schema: t.Optional[Schema] = None,
) -> E:
"""
Rewrite sqlglot AST to have fully qualified tables. Additionally, this
replaces "join constructs" (*) by equivalent SELECT * subqueries.
@ -21,19 +29,17 @@ def qualify_tables(expression, db=None, catalog=None, schema=None):
'SELECT * FROM (SELECT * FROM tbl1 AS tbl1 JOIN tbl2 AS tbl2 ON id1 = id2) AS _q_0'
Args:
expression (sqlglot.Expression): expression to qualify
db (str): Database name
catalog (str): Catalog name
expression: Expression to qualify
db: Database name
catalog: Catalog name
schema: A schema to populate
Returns:
sqlglot.Expression: qualified expression
The qualified expression.
(*) See section 7.2.1.2 in https://www.postgresql.org/docs/current/queries-table-expressions.html
"""
sequence = itertools.count()
next_name = lambda: f"_q_{next(sequence)}"
next_alias_name = name_sequence("_q_")
for scope in traverse_scope(expression):
for derived_table in itertools.chain(scope.ctes, scope.derived_tables):
@ -44,10 +50,14 @@ def qualify_tables(expression, db=None, catalog=None, schema=None):
derived_table.this.replace(exp.select("*").from_(unnested.copy(), copy=False))
if not derived_table.args.get("alias"):
alias_ = f"_q_{next(sequence)}"
alias_ = next_alias_name()
derived_table.set("alias", exp.TableAlias(this=exp.to_identifier(alias_)))
scope.rename_source(None, alias_)
pivots = derived_table.args.get("pivots")
if pivots and not pivots[0].alias:
pivots[0].set("alias", exp.TableAlias(this=exp.to_identifier(next_alias_name())))
for name, source in scope.sources.items():
if isinstance(source, exp.Table):
if isinstance(source.this, exp.Identifier):
@ -59,12 +69,19 @@ def qualify_tables(expression, db=None, catalog=None, schema=None):
if not source.alias:
source = source.replace(
alias(
source.copy(),
name if name else next_name(),
source,
name or source.name or next_alias_name(),
copy=True,
table=True,
)
)
pivots = source.args.get("pivots")
if pivots and not pivots[0].alias:
pivots[0].set(
"alias", exp.TableAlias(this=exp.to_identifier(next_alias_name()))
)
if schema and isinstance(source.this, exp.ReadCSV):
with csv_reader(source.this) as reader:
header = next(reader)
@ -74,11 +91,11 @@ def qualify_tables(expression, db=None, catalog=None, schema=None):
)
elif isinstance(source, Scope) and source.is_udtf:
udtf = source.expression
table_alias = udtf.args.get("alias") or exp.TableAlias(this=next_name())
table_alias = udtf.args.get("alias") or exp.TableAlias(this=next_alias_name())
udtf.set("alias", table_alias)
if not table_alias.name:
table_alias.set("this", next_name())
table_alias.set("this", next_alias_name())
if isinstance(udtf, exp.Values) and not table_alias.columns:
for i, e in enumerate(udtf.expressions[0].expressions):
table_alias.append("columns", exp.to_identifier(f"_col_{i}"))