Refresh a Materialized View Concurrently
Refresh the materialized view concurrently so readers never block and the dashboard stays available during the refresh.
Task
Apply REFRESH MATERIALIZED VIEW CONCURRENTLY daily_stats; so the schema change is safe, reversible, and does not lock the table during peak traffic.
When to use this
A migration deploys REFRESH MATERIALIZED VIEW CONCURRENTLY daily_stats; during peak hours, takes a 40-second lock, and causes a connection pool exhaustion.
Prerequisites
- A database with migration tooling configured
- A staging environment mirroring production schema
Steps
1. Configure REFRESH MATERIALIZED VIEW CONCURRENTLY daily_stats; in the project configuration file with the recommended defaults.
REFRESH MATERIALIZED VIEW CONCURRENTLY daily_stats;
Expected output: The configuration is accepted and REFRESH MATERIALIZED VIEW CONCURRENTLY daily_stats; runs without errors on the first invocation.
2. Run the check locally to verify REFRESH MATERIALIZED VIEW CONCURRENTLY daily_stats; produces the expected result before pushing.
pnpm test
Expected output: Local run matches CI behavior; no surprises after push.
3. Add the gate to the CI pipeline so REFRESH MATERIALIZED VIEW CONCURRENTLY daily_stats; blocks merge on failure.
- name: Run add matview concurrent refresh
run: pnpm test
Expected output: Pull requests with failing REFRESH MATERIALIZED VIEW CONCURRENTLY daily_stats; are blocked from merging.
Troubleshooting
Problem
The check passes locally but fails in CI
Solution
Pin dependency versions and the runtime to match CI exactly; reproduce with the same Docker image or act.
Problem
Configuration is rejected with a schema error
Solution
Check the tool version matches the config schema; older versions may not support newer fields.
Limitations
- The gate only runs on events that trigger the workflow; locally pushed commits bypass it.
- Configuration drift is possible if someone edits settings outside version control.
Make migrations safe
Start by measuring the problem. Refresh the materialized view concurrently so readers never block and the dashboard stays available during the refresh. The most common mistake is adding the gate without first confirming it catches the issue you care about. Run REFRESH MATERIALIZED VIEW CONCURRENTLY daily_stats; against the current codebase and inspect the output before wiring it into CI.
REFRESH MATERIALIZED VIEW CONCURRENTLY daily_stats;Verify and roll back
Once the gate is in place, make failures actionable. A failing REFRESH MATERIALIZED VIEW CONCURRENTLY daily_stats; should point to the exact file and line, not a generic error. Pin the tool version in the lockfile so a upstream release does not silently change behavior. Review the gate output in every pull request just like a test result.