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Merging upstream version 17.7.0.

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Signed-off-by: Daniel Baumann <daniel@debian.org>
This commit is contained in:
Daniel Baumann 2025-02-13 20:46:55 +01:00
parent 87252470ef
commit 137902868c
Signed by: daniel
GPG key ID: FBB4F0E80A80222F
93 changed files with 41580 additions and 39040 deletions
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3
sqlglot/optimizer/eliminate_subqueries.py
View file

@ -144,8 +144,9 @@ def _eliminate_derived_table(scope, existing_ctes, taken):
name, cte = _new_cte(scope, existing_ctes, taken)
table = exp.alias_(exp.table_(name), alias=parent.alias or name)
parent.replace(table)
table.set("joins", parent.args.get("joins"))
parent.replace(table)
return cte

2
sqlglot/optimizer/merge_subqueries.py
View file

@ -176,6 +176,7 @@ def _mergeable(outer_scope, inner_scope, leave_tables_isolated, from_or_join):
return (
isinstance(outer_scope.expression, exp.Select)
and not outer_scope.expression.is_star
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")
@ -242,6 +243,7 @@ def _merge_from(outer_scope, inner_scope, node_to_replace, alias):
alias (str)
"""
new_subquery = inner_scope.expression.args["from"].this
new_subquery.set("joins", node_to_replace.args.get("joins"))
node_to_replace.replace(new_subquery)
for join_hint in outer_scope.join_hints:
tables = join_hint.find_all(exp.Table)

3
sqlglot/optimizer/pushdown_projections.py
View file

@ -61,6 +61,9 @@ def pushdown_projections(expression, schema=None, remove_unused_selections=True)
if remove_unused_selections:
_remove_unused_selections(scope, parent_selections, schema)
if scope.expression.is_star:
continue
# Group columns by source name
selects = defaultdict(set)
for col in scope.columns:

15
sqlglot/optimizer/qualify_columns.py
View file

@ -29,12 +29,13 @@ def qualify_columns(
'SELECT tbl.col AS col FROM tbl'
Args:
expression: expression to qualify
schema: Database schema
expand_alias_refs: whether or not to expand references to aliases
infer_schema: whether or not to infer the schema if missing
expression: Expression to qualify.
schema: Database schema.
expand_alias_refs: Whether or not to expand references to aliases.
infer_schema: Whether or not to infer the schema if missing.
Returns:
sqlglot.Expression: qualified expression
The qualified expression.
"""
schema = ensure_schema(schema)
infer_schema = schema.empty if infer_schema is None else infer_schema
@ -410,7 +411,9 @@ def _expand_stars(
else:
return
scope.expression.set("expressions", new_selections)
# Ensures we don't overwrite the initial selections with an empty list
if new_selections:
scope.expression.set("expressions", new_selections)
def _add_except_columns(

32
sqlglot/optimizer/scope.py
View file

@ -124,8 +124,8 @@ class Scope:
self._ctes.append(node)
elif (
isinstance(node, exp.Subquery)
and isinstance(parent, (exp.From, exp.Join))
and _is_subquery_scope(node)
and isinstance(parent, (exp.From, exp.Join, exp.Subquery))
and _is_derived_table(node)
):
self._derived_tables.append(node)
elif isinstance(node, exp.Subqueryable):
@ -610,13 +610,13 @@ def _traverse_ctes(scope):
scope.sources.update(sources)
def _is_subquery_scope(expression: exp.Subquery) -> bool:
def _is_derived_table(expression: exp.Subquery) -> bool:
"""
We represent (tbl1 JOIN tbl2) as a Subquery, but it's not really a new scope.
If an alias is present, it shadows all names under the Subquery, so that's an
exception to this rule.
We represent (tbl1 JOIN tbl2) as a Subquery, but it's not really a "derived table",
as it doesn't introduce a new scope. If an alias is present, it shadows all names
under the Subquery, so that's one exception to this rule.
"""
return bool(not isinstance(expression.unnest(), exp.Table) or expression.alias)
return bool(expression.alias or isinstance(expression.this, exp.Subqueryable))
def _traverse_tables(scope):
@ -654,7 +654,10 @@ def _traverse_tables(scope):
else:
sources[source_name] = expression
expressions.extend(join.this for join in expression.args.get("joins") or [])
# Make sure to not include the joins twice
if expression is not scope.expression:
expressions.extend(join.this for join in expression.args.get("joins") or [])
continue
if not isinstance(expression, exp.DerivedTable):
@ -664,10 +667,11 @@ def _traverse_tables(scope):
lateral_sources = sources
scope_type = ScopeType.UDTF
scopes = scope.udtf_scopes
elif _is_subquery_scope(expression):
elif _is_derived_table(expression):
lateral_sources = None
scope_type = ScopeType.DERIVED_TABLE
scopes = scope.derived_table_scopes
expressions.extend(join.this for join in expression.args.get("joins") or [])
else:
# Makes sure we check for possible sources in nested table constructs
expressions.append(expression.this)
@ -735,10 +739,16 @@ def walk_in_scope(expression, bfs=True):
isinstance(node, exp.CTE)
or (
isinstance(node, exp.Subquery)
and isinstance(parent, (exp.From, exp.Join))
and _is_subquery_scope(node)
and isinstance(parent, (exp.From, exp.Join, exp.Subquery))
and _is_derived_table(node)
)
or isinstance(node, exp.UDTF)
or isinstance(node, exp.Subqueryable)
):
prune = True
if isinstance(node, (exp.Subquery, exp.UDTF)):
# The following args are not actually in the inner scope, so we should visit them
for key in ("joins", "laterals", "pivots"):
for arg in node.args.get(key) or []:
yield from walk_in_scope(arg, bfs=bfs)