Postgres
Renaming a column without downtime: expand, migrate, contract
ALTER TABLE ... RENAME COLUMN takes a millisecond and breaks every running pod. A step-by-step expand and contract rename in Postgres, with the trigger we use.
Topic · 4 stories
Postgres
Indexes, query plans, migrations and the locks behind them, written from the point of view of the team that owns the database.
Tooling
Feature flags without a vendor: one table, one function, one rule
For most teams, feature flags are a Postgres table, a hashing function and a policy about expiry dates. Here is ours, and when we would pay for a product instead.
Postgres
The index that did nothing: reading an EXPLAIN plan line by line
We added an index to fix a 1.2 second query and the plan did not change. Here is how EXPLAIN ANALYZE told us why, and the partial index that worked.
Reliability
Idempotency keys for webhooks: the ten lines that stop double charges
Webhook providers deliver at least once, so your handler will see duplicates. A unique key and one transaction in Postgres make that harmless.