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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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17
sqlglot/optimizer/merge_subqueries.py
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@ -13,15 +13,15 @@ def merge_subqueries(expression, leave_tables_isolated=False):
Example:
>>> import sqlglot
>>> expression = sqlglot.parse_one("SELECT a FROM (SELECT x.a FROM x) JOIN y")
>>> expression = sqlglot.parse_one("SELECT a FROM (SELECT x.a FROM x) CROSS JOIN y")
>>> merge_subqueries(expression).sql()
'SELECT x.a FROM x JOIN y'
'SELECT x.a FROM x CROSS JOIN y'
If `leave_tables_isolated` is True, this will not merge inner queries into outer
queries if it would result in multiple table selects in a single query:
>>> expression = sqlglot.parse_one("SELECT a FROM (SELECT x.a FROM x) JOIN y")
>>> expression = sqlglot.parse_one("SELECT a FROM (SELECT x.a FROM x) CROSS JOIN y")
>>> merge_subqueries(expression, leave_tables_isolated=True).sql()
'SELECT a FROM (SELECT x.a FROM x) JOIN y'
'SELECT a FROM (SELECT x.a FROM x) CROSS JOIN y'
Inspired by https://dev.mysql.com/doc/refman/8.0/en/derived-table-optimization.html
@ -154,7 +154,7 @@ def _mergeable(outer_scope, inner_scope, leave_tables_isolated, from_or_join):
inner_from = inner_scope.expression.args.get("from")
if not inner_from:
return False
inner_from_table = inner_from.expressions[0].alias_or_name
inner_from_table = inner_from.alias_or_name
inner_projections = {s.alias_or_name: s for s in inner_scope.selects}
return any(
col.table != inner_from_table
@ -167,6 +167,7 @@ def _mergeable(outer_scope, inner_scope, leave_tables_isolated, from_or_join):
and isinstance(inner_select, exp.Select)
and not any(inner_select.args.get(arg) for arg in UNMERGABLE_ARGS)
and inner_select.args.get("from")
and not outer_scope.pivots
and not any(e.find(exp.AggFunc, exp.Select) for e in inner_select.expressions)
and not (leave_tables_isolated and len(outer_scope.selected_sources) > 1)
and not (
@ -210,7 +211,7 @@ def _rename_inner_sources(outer_scope, inner_scope, alias):
elif isinstance(source, exp.Table) and source.alias:
source.set("alias", new_alias)
elif isinstance(source, exp.Table):
source.replace(exp.alias_(source.copy(), new_alias))
source.replace(exp.alias_(source, new_alias))
for column in inner_scope.source_columns(conflict):
column.set("table", exp.to_identifier(new_name))
@ -228,7 +229,7 @@ def _merge_from(outer_scope, inner_scope, node_to_replace, alias):
node_to_replace (exp.Subquery|exp.Table)
alias (str)
"""
new_subquery = inner_scope.expression.args.get("from").expressions[0]
new_subquery = inner_scope.expression.args["from"].this
node_to_replace.replace(new_subquery)
for join_hint in outer_scope.join_hints:
tables = join_hint.find_all(exp.Table)
@ -319,7 +320,7 @@ def _merge_where(outer_scope, inner_scope, from_or_join):
# Merge predicates from an outer join to the ON clause
# if it only has columns that are already joined
from_ = expression.args.get("from")
sources = {table.alias_or_name for table in from_.expressions} if from_ else {}
sources = {from_.alias_or_name} if from_ else {}
for join in expression.args["joins"]:
source = join.alias_or_name