PostgreSQL Enterprise & Performance
5-8 Years (Senior)
Medium
Production Scenario
How do you perform Zero-Downtime Index Creation in PostgreSQL using `CONCURRENTLY`?
Real-World Scenario / Incident Description
Creating an index on a 40M row production table threw timeout errors and locked incoming user registrations.
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Updated 1 month ago
CREATE INDEX CONCURRENTLY
Standard CREATE INDEX takes an ACCESS EXCLUSIVE lock blocking writes.
CREATE INDEX CONCURRENTLY idx_users_email ON users (email);
- Scans table twice and builds the index without blocking
INSERT/UPDATE/DELETEoperations. - Note: Cannot run inside a multi-statement transaction block.
Related Concepts:
#CREATE INDEX CONCURRENTLY
#Zero Downtime
#PostgreSQL
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