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Pull request overview
This pull request refactors the MVCC (Multi-Version Concurrency Control) commit logic to reduce code duplication and adds correctness assertions. The PR depends on #5596 which added initial MVCC correctness asserts, and this PR continues that work with additional refactoring.
Changes:
- Extracted common read-only transaction commit logic into
commit_read_only_txhelper function - Extracted version timestamp conversion logic into
convert_version_timestampshelper function - Added runtime assertions to enforce MVCC invariants (transactions not depending on themselves, proper timestamp ordering)
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Extract commit_read_only_tx() to unify the read-only transaction commit logic used by both the Initial fast-path and the WaitForDependencies path. The WaitForDependencies path previously called pager_commit_lock.unlock() directly inside the is_exclusive_tx guard, while Initial used unlock_commit_lock_if_held(). Both were correct (exclusive txs always hold the commit lock), but the helper is used now for consistency.
Deduplicate the TxID-to-Timestamp conversion loops for table rows and index rows during commit postprocessing. The same logic (match begin/end against tx_id, replace with Timestamp, append to log_record, check sqlite_schema) was repeated for both row types.
avinassh
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Description
Depends on #5596