Prevent sorting and count queries for non-SELECT statements.

[kssumin]

Changes

This PR addresses issue #2856 by adding proper validation to QueryEnhancer implementations to prevent invalid operations on non-SELECT statements.

Summary

Previously, QueryEnhancer would silently return default values or apply inappropriate operations when attempting to:

• Create count queries for INSERT/UPDATE/DELETE/MERGE statements
• Apply sorting to INSERT/UPDATE/DELETE/MERGE statements

This behavior was problematic as it could lead to unexpected results or silent failures.

What Changed

1. Statement Type Detection

   • Added StatementType enum to QueryInformation class
   • Implemented statement type detection using regex pattern matching in DefaultQueryEnhancer
   • Extended introspector classes (JpqlQueryIntrospector, HqlQueryIntrospector, EqlQueryIntrospector) to detect and propagate statement types

2. Validation Logic

   • QueryEnhancer.rewrite(): Now throws IllegalStateException when attempting to apply sorting to non-SELECT statements
   • QueryEnhancer.createCountQueryFor(): Now throws IllegalStateException when attempting to create count queries for non-SELECT statements
   • Unsorted rewriting is still allowed for all statement types (no-op behavior)

3. Affected Classes

   • DefaultQueryEnhancer: Added statement type detection and validation
   • JpaQueryEnhancer: Added validation for sorting and count queries
   • JSqlParserQueryEnhancer: Changed from returning original query to throwing exceptions
   • QueryInformation: Added StatementType enum and helper methods
   • HibernateQueryInformation: Extended to support statement type

4. Test Coverage

   • Added test cases to QueryEnhancerUnitTests for JPQL queries:
     • INSERT/UPDATE/DELETE statements throwing exceptions for count queries
     • INSERT/UPDATE/DELETE statements throwing exceptions for sorting
     • Unsorted operations working for all statement types
   • Added test cases to JSqlParserQueryEnhancerUnitTests for native queries:
     • INSERT/UPDATE statements throwing exceptions for count queries and sorting
     • Unsorted operations working for all statement types

Closes: #2856

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[mp911de]

Thank you for your contribution. That's merged and polished now.

The summary above looks as if it was AI-generated from the changeset which is basically repeating all technical aspects that are immediately visible from the change itself. For the future, descriptions should rather talk about the motivation and aspects that are introduced by a change as repeating what the diff is going to contain is rather noise and distracting from the actual change.