Proposed features:

1. Database as a directory
2. Table as a text file
3. String-typed data
4. Create/rename/delete tables
5. Add/rename/remove columns
6. Insert/update/delete rows
7. Relational algebras - multi-table join, select, project, union, redefine)
8. Order relational algebra result by column
9. Transaction management - commit and rollback support
10. Shared and exclusive table locks - implementation does not rely on flock()
11. Crash-on-read does not corrupt data
12. Crash-on-write is recoverable by calling a repairing function