schema change
Database migration
Database Migration
Also known as · DB migration · schema migration · DDL change
Definition
A versioned change that moves operational data structures or constraints from one state to the next. Successful SQL syntax is a separate judgment from compatibility and recoverability.
Searchable examples
- CREATE INDEX CONCURRENTLY
- forward fix
Short example
create table → verify schema → backfill → verify reads/writes
When a change is already applied, a forward-fix migration may be safer than pretending it never happened.