ROWNUM Pseudocolumn Implementation - Test Cases and Implementation Guide

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ROWNUM Pseudocolumn Implementation

This issue tracks the implementation of Oracle ROWNUM pseudocolumn support in IvorySQL.

Related to: IvorySQL#41

Documentation

All design documentation, test cases, and Oracle behavior verification are tracked in the repository:

• Design Document: design/rownum/design.md
• Test Suite: design/rownum/test_rownum_oracle.sql (15 comprehensive tests)
• Oracle Test Results: design/rownum/test_rownum_oracle_results.md

Quick Summary

ROWNUM is an Oracle pseudocolumn that returns sequential numbers (1, 2, 3...) as rows are retrieved. It has special behavior:

• ✅ WHERE ROWNUM <= N - Works (returns first N rows)
• ❌ WHERE ROWNUM > 1 - Returns NO rows (critical Oracle quirk)
• ⚠️ ROWNUM assigned before ORDER BY

Implementation Status

See the design document for the complete implementation checklist covering Parser, Optimizer, and Executor layers.

Branch: feat/rownum