ROADMAP.md

Roadmap

This document is an extended TODO list. It is useful if you want to:

• continue development
• pick a focused topic (optimization, indexes, transactions)
• use this repository as a reference for your own educational project

Indexes and optimization

• BTREE persistence: on-disk format, recovery without rebuild, restart tests.
• Expand plan selection: more rules for predicates and compound conditions.
• Cost-based optimizer: statistics, selectivity estimation, operator choice.
• Multi-column (composite) indexes.

SQL dialect

• UPDATE
• DELETE
• DROP TABLE
• DROP INDEX
• ORDER BY
• LIMIT
• JOIN (start with nested loop join)

Transactions and concurrency

• Remove global query serialization (server-level lock).
• Table/page/row-level locking.
• MVCC or a simplified isolation model (e.g., Read Committed).
• Transaction log (WAL) for durability.

Storage engine

• Stronger flush/close guarantees, educational crash-recovery tests.
• Better free-space management and page compaction.
• Table statistics: row counts and value distributions.

Tooling and DX

• Load test scenarios (benchmarks).
• Better error messages (SQL positions, context).
• CI pipeline (build + tests).