Walkthrough

This PR fixes incorrect LIMIT result handling when negative LIMIT values are used within subqueries and UNION operations. A state management issue in LimitRecordCursorFactory is addressed by resetting skipToRows to -1 after row skipping, and a corresponding test validates the fix.

Changes

Sequence Diagram

sequenceDiagram
    participant Cursor as LimitRecordCursor
    participant SkipRows as skipRows()
    
    Cursor->>SkipRows: skipRows(skippedRows)
    Note over SkipRows: May modify skipToRows<br/>during execution
    SkipRows-->>Cursor: Returns control
    
    rect rgb(240, 248, 255)
        Note over Cursor: FIX: Reset state
        Cursor->>Cursor: skipToRows = -1
    end
    
    Note over Cursor: State preserved for<br/>negative limit handling

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~8 minutes

• The core fix is a single-line assignment ensuring proper state reset in a localized method
• Test method addition follows standard patterns and is straightforward to validate
• Minimal surface area: two distinct changes with clear purposes
• The fix addresses a specific state management concern rather than broad refactoring

Areas requiring attention:

• Verify that resetting skipToRows = -1 after skipRows() does not interfere with other execution paths or cursor lifecycle states
• Confirm the test's assertion logic correctly validates both the result set (expected timestamps) and the execution plan structure for negative LIMIT handling
• Ensure the fix applies universally to all contexts where toTop() is called, particularly in nested/union query scenarios

Suggested reviewers

• RaphDal

Pre-merge checks and finishing touches

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[PR Coverage check]

😍 pass : 1 / 1 (100.00%)

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