AboEl3iz opened a new pull request, #24818:
URL: https://github.com/apache/datafusion/pull/24818
## Which issue does this PR close?
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- Closes #24816
## Rationale for this change
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When an aggregate query contains both supported expressions (such as
`MIN(a)`) and unsupported expressions (such as `MIN(c + 1)`), DataFusion
previously built a dynamic filter using only the supported expressions.
Because all aggregate expressions in an `AggregateExec` share the same input
scan stream, pushing a dynamic filter constructed from a subset of aggregate
expressions prunes rows required by the unsupported expressions, producing
incorrect aggregate results.
Aggregate dynamic filter pushdown must be an all-or-nothing optimization: if
any aggregate expression in the `AggregateExec` cannot produce a valid dynamic
filter predicate, dynamic filtering must be disabled (`dynamic_filter = None`)
for that node.
## What changes are included in this PR?
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- Updated `AggregateExec::init_dynamic_filter` in
`datafusion/physical-plan/src/aggregates/mod.rs` to return early when an
aggregate argument is not a single `Column` reference.
- Added unit test
`test_dynamic_filter_disabled_when_unsupported_expr_present` in
`datafusion/physical-plan/src/aggregates/mod.rs`.
- Added integration test
`dynamic_rg_pruning_disabled_when_unsupported_aggregate_present` in
`datafusion/core/tests/parquet/dynamic_row_group_pruning.rs` reproducing issue
#24816.
## What is the testing strategy for this PR?
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- Unit test: `test_dynamic_filter_disabled_when_unsupported_expr_present` in
`datafusion-physical-plan` checks that `dynamic_filter` remains `None` when an
unsupported expression like `MIN(a + 1)` is present.
- Integration test:
`dynamic_rg_pruning_disabled_when_unsupported_aggregate_present` in
`datafusion/core/tests/parquet/dynamic_row_group_pruning.rs` verifies that
queries with `MIN(a), MAX(a), MAX(b), MIN(c + 1)` evaluate correctly (`71`)
without row groups being pruned.
## Are there any user-facing changes?
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No breaking API or user-facing changes. Correctness fix for aggregate
queries with dynamic filter pushdown.
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