In many projects the database schema lives in the database instead of the repository — grown out of years of hand-run ALTERs, fully documented nowhere. It only becomes visible when a second environment is needed or a deploy breaks. Postgres database CI/CD flips that relationship: the repository describes the desired state, and every environment — from the throwaway … Read more
The bug was a typo in an ALTER TABLE — and it was found by the staging deploy on a Friday afternoon. Yet that exact find is automatable: set up a GitHub Actions Postgres deployment against a throwaway database, and every pull request becomes a full dress rehearsal. Syntax and semantic errors, ordering problems, and broken idempotency surface before … Read more
The backfill ran a second time on the second deploy — and overwrote values that had been corrected by the business in the meantime. Accidents like this are not prevented by discipline, only by a memory: if you want to track database schema changes without introducing Flyway or Liquibase, all it takes is exactly one table and … Read more
The ALTER TABLE ran through cleanly on your machine — on staging, the same deploy fails with column “country_code” of relation “customer” contains null values. The difference is not the SQL, it is the data: the local table was empty, the one on staging was not. If you want to add a NOT NULL column to an existing table that … Read more
