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index-concurrently

CREATE INDEX without CONCURRENTLY — locks the table against writes.

SARJ108 Rule source Tests Catalog JSON

Why

Building an index normally blocks writes to an existing PostgreSQL table for the duration of the build.

Fix

Use CREATE INDEX CONCURRENTLY in a nontransactional migration.

Examples

Before — flagged Blocking index build on an existing table

migrations/002_email_index.sql

CREATE INDEX users_email_idx ON users (email);

After — preferred Concurrent index build

migrations/002_email_index.sql

CREATE INDEX CONCURRENTLY users_email_idx ON users (email);