DM-55685: Expanded aggregation support

[malensek]

The query analysis AggregatePlugin previously assumed a flat, top-level list of expressions from the parser adapter. As a result, the adapter layer restricted aggregations to simple column references only. This change enables the plugin to handle both a flat list of expressions from the legacy adapter as well as a potentially deeper tree of expressions produced by the Hyrise adapter.

Additionally, this change enables BIT_ aggregations, since they can be split and merged via AccumulateOp like MIN, MAX, SUM.

Here are some of the new possibilities supported by this change (using the qcase02 test dataset):

SELECT ROUND(100.0 * COUNT(yFlags) / COUNT(*), 1) FROM qcase02.Object;
SELECT MAX(ABS(decl_PS)) FROM qcase02.Object;
SELECT MAX(objectId + 1) FROM qcase02.Object;
SELECT MIN(LENGTH(objectId)) FROM qcase02.Object;
SELECT 25 + SUM(uNumObs) + 100 FROM qcase02.Object;
SELECT BIT_OR(uFlags & 255) FROM qcase02.Object;

Summary of Changes

• AggregatePlugin now recursively traverses ValueExpr and ValueFactor trees
• SchemaFactory now preserves UNSIGNED_FLAG when creating integer columns
• BIT_XOR, BIT_AND, BIT_OR are now allowed by the parser adapter and processed in query analysis
• HAVING aggregations that can't be resolved are now rejected up front
• New unit and integration tests for this functionality

Related issues (existing behavior, being tracked in DM-56009):

• HAVING with non-aggregate expressions are not currently validated against the SELECT list
• GROUP BY keys are not validated against the SELECT list
• SELECT * does not populate _usedValueExprs, so nothing in ORDER BY / HAVING matches

[Copilot]

🟡 Changes recommended

Critical aggregate-placement and grouped-merge planning issues remain unresolved.

Once you've addressed the issues Copilot identified, you can request another Copilot review.

Pull request overview

Expands distributed aggregation to support nested expressions, bitwise aggregates, and unsigned intermediate result types.

Changes:

• Recursively detects and rewrites aggregate expression trees.
• Adds BIT_AND, BIT_OR, and BIT_XOR support.
• Adds unit and integration coverage.

File summaries

File	Description
src/query/ValueFactor.h	Declares recursive aggregation detection.
src/query/ValueFactor.cc	Implements recursive factor traversal.
src/query/ValueExpr.cc	Delegates aggregation detection to factors.
src/query/AggOp.cc	Adds bitwise accumulation operations.
src/qproc/testQueryAnaAggregation.cc	Tests rewritten plans; critically, a grouped merge expects chunkId that the parallel query does not emit.
src/qana/CheckAggregation.h	Removes the obsolete shallow checker.
src/qana/AggregatePlugin.cc	Recursively rewrites aggregate trees.
src/mysql/SchemaFactory.cc	Preserves unsigned integer metadata.
src/ccontrol/testHyriseGeneratedIR.cc	Updates adapter aggregation tests.
src/ccontrol/HyriseAdapter.cc	Expands aggregate parsing; critically, invalid aggregate placements beyond WHERE, including HAVING, are not safely rejected or rewritten.
data/case01/queries/2117_nestedAggregateExpressionGroupBy.sql	Tests grouped nested aggregation.
data/case01/queries/2116_nestedAggregateExpression.sql	Tests nested aggregate arithmetic.
data/case01/queries/2115_bitwiseAggregatesEmptyInput.sql	Tests empty-input identities.
data/case01/queries/2114_bitwiseAggregateWideValue.sql	Tests unsigned 64-bit results.
data/case01/queries/2113_bitwiseAggregateExpression.sql	Tests expression arguments.
data/case01/queries/2112_bitwiseAggregatesGroupBy.sql	Tests grouped bitwise aggregation.
data/case01/queries/2111_bitwiseAggregatesEmptyChunks.sql	Tests empty worker chunks.
data/case01/queries/2110_bitwiseAggregates.sql	Tests basic bitwise aggregates.

Review details

• Files reviewed: 18/18 changed files
• Comments generated: 2
• Review effort level: Balanced

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[Copilot]

🟢 Approval recommended

The recursive rewrite, placement validation, schema handling, and edge cases are covered consistently by focused unit and integration tests.

Review details

• Files reviewed: 21/21 changed files
• Comments generated: 0 new
• Review effort level: Balanced