branch-4.1: [fix](mv) Align extra-join elimination safety check #62527#63139
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Problem Summary:
Extra-join elimination rejected some safe LEFT JOIN rewrites too early.
When the right side was guaranteed unique, a LEFT JOIN could still be
safely eliminated even if its ON clause contained right-side
`otherJoinConjuncts`, because those predicates only decide whether the
nullable side matches and do not filter preserved-side rows.
Example:
-- MV
SELECT t1.id, t1.name
FROM t1
LEFT JOIN t2
ON t1.id = t2.id AND t2.id = 1
-- Query
SELECT id, name FROM t1
If `t2.id` is unique and no output or residual filter depends on `t2`,
eliminating `t2` is safe.
This PR relaxes the MV comparison path for that LEFT JOIN case, while
still rejecting eliminations when unmatched residual filters depend on
the eliminated side. For example, filters above the join such as `WHERE
t2.id IS NULL`, or INNER JOIN filters such as `WHERE lineitem.l_shipdate
= '2024-01-01'`, cannot be dropped because they affect which
preserved-side rows survive.
To make that safety check precise, `FilterEdge` now records the actual
input nodes of its predicates during HyperGraph construction, including
projected aliases and slot-free predicates.
Co-authored-by: yangtao555 <yangtao555@jd.com>
Co-authored-by: Dongyang Li <lidongyang@selectdb.com>
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yiguolei
approved these changes
May 11, 2026
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Cherry-picked from #62527