Tag
schema-migrations
- Oct 8, 2025 Which ALTER TABLE Statements Rewrite the Table and Which Only Touch the Catalogue How engines decide between a catalogue edit and a full table copy, what the fast-default and instant-column mechanisms store instead, and where the boundary sits. databases
- Mar 12, 2024 Expand and Contract: Changing a Column While Both Versions Run The four-step sequence that lets old and new application code share one schema, which intermediate states must be safe, and where the sequence breaks down. databases
- Sep 26, 2022 How a Migration Runner Records and Orders Applied Versions The ledger table, version ordering, checksums, and locking that make a migration run reproducible, and what happens when two runners start at the same time. databases