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Merging upstream version 6.3.1.

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Signed-off-by: Daniel Baumann <daniel@debian.org>
This commit is contained in:
Daniel Baumann 2025-02-13 14:45:11 +01:00
parent 81e6900b0a
commit 393757f998
Signed by: daniel
GPG key ID: FBB4F0E80A80222F
41 changed files with 1558 additions and 267 deletions
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44
sqlglot/optimizer/merge_subqueries.py
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@ -44,6 +44,7 @@ UNMERGABLE_ARGS = set(exp.Select.arg_types) - {
"joins",
"where",
"order",
"hint",
}
@ -67,21 +68,22 @@ def merge_ctes(expression, leave_tables_isolated=False):
singular_cte_selections = [v[0] for k, v in cte_selections.items() if len(v) == 1]
for outer_scope, inner_scope, table in singular_cte_selections:
inner_select = inner_scope.expression.unnest()
if _mergeable(outer_scope, inner_select, leave_tables_isolated):
from_or_join = table.find_ancestor(exp.From, exp.Join)
from_or_join = table.find_ancestor(exp.From, exp.Join)
if _mergeable(outer_scope, inner_select, leave_tables_isolated, from_or_join):
node_to_replace = table
if isinstance(node_to_replace.parent, exp.Alias):
node_to_replace = node_to_replace.parent
alias = node_to_replace.alias
else:
alias = table.name
_rename_inner_sources(outer_scope, inner_scope, alias)
_merge_from(outer_scope, inner_scope, node_to_replace, alias)
_merge_expressions(outer_scope, inner_scope, alias)
_merge_joins(outer_scope, inner_scope, from_or_join)
_merge_where(outer_scope, inner_scope, from_or_join)
_merge_order(outer_scope, inner_scope)
_merge_hints(outer_scope, inner_scope)
_pop_cte(inner_scope)
return expression
@ -90,9 +92,9 @@ def merge_derived_tables(expression, leave_tables_isolated=False):
for outer_scope in traverse_scope(expression):
for subquery in outer_scope.derived_tables:
inner_select = subquery.unnest()
if _mergeable(outer_scope, inner_select, leave_tables_isolated):
from_or_join = subquery.find_ancestor(exp.From, exp.Join)
if _mergeable(outer_scope, inner_select, leave_tables_isolated, from_or_join):
alias = subquery.alias_or_name
from_or_join = subquery.find_ancestor(exp.From, exp.Join)
inner_scope = outer_scope.sources[alias]
_rename_inner_sources(outer_scope, inner_scope, alias)
@ -101,10 +103,11 @@ def merge_derived_tables(expression, leave_tables_isolated=False):
_merge_joins(outer_scope, inner_scope, from_or_join)
_merge_where(outer_scope, inner_scope, from_or_join)
_merge_order(outer_scope, inner_scope)
_merge_hints(outer_scope, inner_scope)
return expression
def _mergeable(outer_scope, inner_select, leave_tables_isolated):
def _mergeable(outer_scope, inner_select, leave_tables_isolated, from_or_join):
"""
Return True if `inner_select` can be merged into outer query.
@ -112,6 +115,7 @@ def _mergeable(outer_scope, inner_select, leave_tables_isolated):
outer_scope (Scope)
inner_select (exp.Select)
leave_tables_isolated (bool)
from_or_join (exp.From|exp.Join)
Returns:
bool: True if can be merged
"""
@ -123,6 +127,16 @@ def _mergeable(outer_scope, inner_select, leave_tables_isolated):
and inner_select.args.get("from")
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 (
isinstance(from_or_join, exp.Join)
and inner_select.args.get("where")
and from_or_join.side in {"FULL", "LEFT", "RIGHT"}
)
and not (
isinstance(from_or_join, exp.From)
and inner_select.args.get("where")
and any(j.side in {"FULL", "RIGHT"} for j in outer_scope.expression.args.get("joins", []))
)
)
@ -170,6 +184,12 @@ def _merge_from(outer_scope, inner_scope, node_to_replace, alias):
"""
new_subquery = inner_scope.expression.args.get("from").expressions[0]
node_to_replace.replace(new_subquery)
for join_hint in outer_scope.join_hints:
tables = join_hint.find_all(exp.Table)
for table in tables:
if table.alias_or_name == node_to_replace.alias_or_name:
new_table = new_subquery.this if isinstance(new_subquery, exp.Alias) else new_subquery
table.set("this", exp.to_identifier(new_table.alias_or_name))
outer_scope.remove_source(alias)
outer_scope.add_source(new_subquery.alias_or_name, inner_scope.sources[new_subquery.alias_or_name])
@ -273,6 +293,18 @@ def _merge_order(outer_scope, inner_scope):
outer_scope.expression.set("order", inner_scope.expression.args.get("order"))
def _merge_hints(outer_scope, inner_scope):
inner_scope_hint = inner_scope.expression.args.get("hint")
if not inner_scope_hint:
return
outer_scope_hint = outer_scope.expression.args.get("hint")
if outer_scope_hint:
for hint_expression in inner_scope_hint.expressions:
outer_scope_hint.append("expressions", hint_expression)
else:
outer_scope.expression.set("hint", inner_scope_hint)
def _pop_cte(inner_scope):
"""
Remove CTE from the AST.