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Merging 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 15:57:23 +01:00
parent 8deb804d23
commit fc63828ee4
Signed by: daniel
GPG key ID: FBB4F0E80A80222F
167 changed files with 58268 additions and 51337 deletions
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19
sqlglot/optimizer/eliminate_subqueries.py
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@ -16,9 +16,9 @@ def eliminate_subqueries(expression):
'WITH y AS (SELECT * FROM x) SELECT a FROM y AS y'
This also deduplicates common subqueries:
>>> expression = sqlglot.parse_one("SELECT a FROM (SELECT * FROM x) AS y JOIN (SELECT * FROM x) AS z")
>>> expression = sqlglot.parse_one("SELECT a FROM (SELECT * FROM x) AS y CROSS JOIN (SELECT * FROM x) AS z")
>>> eliminate_subqueries(expression).sql()
'WITH y AS (SELECT * FROM x) SELECT a FROM y AS y JOIN y AS z'
'WITH y AS (SELECT * FROM x) SELECT a FROM y AS y CROSS JOIN y AS z'
Args:
expression (sqlglot.Expression): expression
@ -32,6 +32,9 @@ def eliminate_subqueries(expression):
root = build_scope(expression)
if not root:
return expression
# Map of alias->Scope|Table
# These are all aliases that are already used in the expression.
# We don't want to create new CTEs that conflict with these names.
@ -112,7 +115,7 @@ def _eliminate_union(scope, existing_ctes, taken):
# Try to maintain the selections
expressions = scope.selects
selects = [
exp.alias_(exp.column(e.alias_or_name, table=alias), alias=e.alias_or_name)
exp.alias_(exp.column(e.alias_or_name, table=alias), alias=e.alias_or_name, copy=False)
for e in expressions
if e.alias_or_name
]
@ -120,7 +123,9 @@ def _eliminate_union(scope, existing_ctes, taken):
if len(selects) != len(expressions):
selects = ["*"]
scope.expression.replace(exp.select(*selects).from_(exp.alias_(exp.table_(alias), alias=alias)))
scope.expression.replace(
exp.select(*selects).from_(exp.alias_(exp.table_(alias), alias=alias, copy=False))
)
if not duplicate_cte_alias:
existing_ctes[scope.expression] = alias
@ -131,6 +136,10 @@ def _eliminate_union(scope, existing_ctes, taken):
def _eliminate_derived_table(scope, existing_ctes, taken):
# This ensures we don't drop the "pivot" arg from a pivoted subquery
if scope.parent.pivots:
return None
parent = scope.expression.parent
name, cte = _new_cte(scope, existing_ctes, taken)
@ -153,7 +162,7 @@ def _eliminate_cte(scope, existing_ctes, taken):
for child_scope in scope.parent.traverse():
for table, source in child_scope.selected_sources.values():
if source is scope:
new_table = exp.alias_(exp.table_(name), alias=table.alias_or_name)
new_table = exp.alias_(exp.table_(name), alias=table.alias_or_name, copy=False)
table.replace(new_table)
return cte