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Merging upstream version 10.4.2.

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Signed-off-by: Daniel Baumann <daniel@debian.org>
This commit is contained in:
Daniel Baumann 2025-02-13 15:01:55 +01:00
parent de4e42d4d3
commit 0c79f8b507
Signed by: daniel
GPG key ID: FBB4F0E80A80222F
88 changed files with 1637 additions and 436 deletions
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47
sqlglot/optimizer/eliminate_joins.py
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@ -129,10 +129,23 @@ def join_condition(join):
"""
name = join.this.alias_or_name
on = (join.args.get("on") or exp.true()).copy()
on = on if isinstance(on, exp.And) else exp.and_(on, exp.true())
source_key = []
join_key = []
def extract_condition(condition):
left, right = condition.unnest_operands()
left_tables = exp.column_table_names(left)
right_tables = exp.column_table_names(right)
if name in left_tables and name not in right_tables:
join_key.append(left)
source_key.append(right)
condition.replace(exp.true())
elif name in right_tables and name not in left_tables:
join_key.append(right)
source_key.append(left)
condition.replace(exp.true())
# find the join keys
# SELECT
# FROM x
@ -141,20 +154,30 @@ def join_condition(join):
#
# should pull y.b as the join key and x.a as the source key
if normalized(on):
on = on if isinstance(on, exp.And) else exp.and_(on, exp.true())
for condition in on.flatten():
if isinstance(condition, exp.EQ):
left, right = condition.unnest_operands()
left_tables = exp.column_table_names(left)
right_tables = exp.column_table_names(right)
extract_condition(condition)
elif normalized(on, dnf=True):
conditions = None
if name in left_tables and name not in right_tables:
join_key.append(left)
source_key.append(right)
condition.replace(exp.true())
elif name in right_tables and name not in left_tables:
join_key.append(right)
source_key.append(left)
condition.replace(exp.true())
for condition in on.flatten():
parts = [part for part in condition.flatten() if isinstance(part, exp.EQ)]
if conditions is None:
conditions = parts
else:
temp = []
for p in parts:
cs = [c for c in conditions if p == c]
if cs:
temp.append(p)
temp.extend(cs)
conditions = temp
for condition in conditions:
extract_condition(condition)
on = simplify(on)
remaining_condition = None if on == exp.true() else on