implement the except (distinct | all ) for table model

[alpass163]

This PR implements the EXCEPT DISTINCT and EXCEPT ALL operators. This is achieved by introducing two new optimizer rules that translate the ExceptNode into a more fundamental execution plan:

(1)ImplementExceptDistinctAsUnion (EXCEPT DISTINCT)

This rule translates EXCEPT DISTINCT into a Union + Aggregation + Filter plan.

It utilizes SetOperationNodeTranslator to append marker columns, then uses Aggregation (GROUP BY) to count the occurrences of each row in each sub-relation.

Finally, a FilterNode selects rows that appear in the first relation (count1 >= 1) but not in any of the subsequent relations (count2...n == 0).

(2)ImplementExceptAllAsUnion (EXCEPT ALL)

This rule translates EXCEPT ALL into a Union + Window + Filter plan.

It uses a Window function to compute the exact occurrence count for each row from each sub-relation (count1, count2...) along with a ROW_NUMBER().

A FilterNode then applies the expression row_number <= greatest(greatest(count1 - count2, 0) - count3...) to precisely implement the bag semantics subtraction required by EXCEPT ALL.

The SetOperationNodeTranslator class contains the core, shared logic used by both translation rules.

[Copilot]

Pull request overview

This PR implements the SQL EXCEPT operator with both DISTINCT and ALL variants for the table model. The implementation follows the same pattern as the existing INTERSECT operator, translating EXCEPT operations into lower-level execution plans using unions, aggregations, and window functions.

Key Changes:

• Introduces ExceptNode as a new logical plan node that extends SetOperationNode
• Adds two optimizer rules: ImplementExceptDistinctAsUnion (translates EXCEPT DISTINCT using Union + Aggregation + Filter) and ImplementExceptAll (translates EXCEPT ALL using Union + Window + Filter)
• Extends existing infrastructure to support ExceptNode (visitors, pattern matchers, optimizers)

Reviewed changes

Copilot reviewed 16 out of 16 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
ExceptNode.java	New logical plan node for EXCEPT operations, mirrors IntersectNode structure
ImplementExceptDistinctAsUnion.java	Optimizer rule that translates EXCEPT DISTINCT to Union + Aggregation + Filter plan
ImplementExceptAll.java	Optimizer rule that translates EXCEPT ALL to Union + Window + Filter plan
SetOperationNodeTranslator.java	Updated comment to reflect usage by both INTERSECT and EXCEPT operations
LogicalOptimizeFactory.java	Registers the new EXCEPT optimizer rules alongside existing set operation rules
UnaliasSymbolReferences.java	Adds visitExcept method to handle symbol aliasing for ExceptNode
Patterns.java	Adds pattern matching support for ExceptNode and removes old commented code
RelationPlanner.java	Implements visitExcept to create ExceptNode during query planning, removes placeholder exception
PlanVisitor.java	Adds visitExcept visitor method for ExceptNode traversal
PlanGraphPrinter.java	Adds visitExcept for plan visualization
PlanNodeType.java	Registers TABLE_EXCEPT_NODE type (1036) for serialization infrastructure
PruneDistinctAggregation.java	Extends optimization to handle EXCEPT DISTINCT nodes
ImplementIntersectDistinctAsUnion.java	Updates GenericLiteral creation to use LongType.INT64.getDisplayName()
TestMetadata.java	Updates SUBTRACT operator handling to use SubtractionResolver for proper type resolution
ExceptTest.java	Unit tests verifying logical plan structure for EXCEPT operations
IoTDBExceptTableIT.java	Integration tests covering EXCEPT DISTINCT, EXCEPT ALL, type compatibility, and error cases

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