Write and Transaction Support in SQLite Virtual Tables

This post delves into the implementation details of write and transaction support in SQLite virtual tables. By implementing hooks like xUpdate, xBegin, xSync, xCommit, and xRollback, virtual tables can support write operations and ensure transactional integrity. The article explains how SQLite's rollback journal and super-journal mechanisms coordinate atomic commits in both single and multi-database scenarios, and how virtual tables participate in this two-phase commit protocol. The author emphasizes that durability must be handled in xSync, while xCommit and xRollback should only perform idempotent cleanup operations, avoiding any operations that could fail.