branch-4.1: [fix](mtmv) Infer null-reject from INNER JoinEdge for multi-hop outer join MV rewrite #62492#62635
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… join MV rewrite (#62492) ### What problem does this PR solve? Related PR: #30374 Problem Summary: In multi-hop LEFT JOIN materialized view transparent rewrite (e.g., `fact LEFT JOIN dim1 LEFT JOIN dim2`), when the query has a WHERE clause that null-rejects only the outermost dimension table (e.g., `WHERE dim2.col = 'value'`), the MV rewrite fails with "Predicate compensate fail". **Root cause:** In `AbstractMaterializedViewRule.containsNullRejectSlot()`, the original code only checked **filter predicates** (`queryPredicates`) for NOT NULL evidence. After the Nereids rewrite pipeline runs: 1. `EliminateOuterJoin` converts all eligible LEFT JOINs → INNER (cascading through `InferJoinNotNull` across multiple passes) 2. `EliminateNotNull` **unconditionally removes** all generated NOT NULL predicates (`isGeneratedIsNotNull=true`) By the time MV rewrite (exploration phase) runs, the query plan has INNER JOINs but **zero NOT NULL filter predicates**. The only surviving predicate is the user's WHERE clause (e.g., `dim2.region_name = 'West'`), which can only prove NOT NULL for outermost dim2 slots — leaving intermediate dim1 slots uncovered. **Fix:** Read INNER JoinEdge conditions directly from the query HyperGraph. After `EliminateOuterJoin` converts LEFT→INNER, JoinEdge objects retain their INNER type and join condition expressions even though `EliminateNotNull` removes filter-level NOT NULL predicates. `ExpressionUtils.inferNotNullSlots()` extracts NOT NULL slots from these INNER join conditions, covering all intermediate join tables. | File | Change Description | |------|-------------------| | `AbstractMaterializedViewRule.java` | `containsNullRejectSlot()`: Add loop over INNER JoinEdges to collect NOT NULL slots from join conditions via `inferNotNullSlots`. Also add `shuttleExpressionWithLineage` for correct slot-level mapping. | | `NullRejectInferenceTest.java` (new) | FE unit test: query=2-hop INNER JOIN vs view=2-hop LEFT JOIN, verifies `predicatesCompensate` succeeds | | `outer_join_two_hop_null_reject.groovy` (new) | Regression test: 3 tables, async MV with 2-hop LEFT JOIN + WHERE + aggregate rollup, verifies rewrite success and result correctness | **2-hop example walkthrough:** ``` Query HyperGraph (after EliminateOuterJoin): JoinEdge 1 (INNER): o.store_id = d.id → {o.store_id, d.id} NOT NULL JoinEdge 2 (INNER): d.id = r.store_id → {d.id, r.store_id} NOT NULL FilterEdge: r.region_name = 'West' → {r.region_name} NOT NULL queryNullRejectSlots = {o.store_id, d.id, r.store_id, r.region_name} requireNoNullableViewSlot (view has LEFT JOINs): Set 1: {d.id, d.store_name} ∩ queryNullRejectSlots → {d.id} ≠ ∅ ✓ Set 2: {r.store_id, r.region_name} ∩ queryNullRejectSlots → {r.store_id, r.region_name} ≠ ∅ ✓ ``` ### Release note Fix multi-hop LEFT JOIN materialized view transparent rewrite failure when the WHERE clause only references the outermost dimension table. --------- Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
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Cherry-picked from #62492