Playbook

Slow DB Query

Identify, analyze, and optimize slow database queries.

Check slow query logs (PostgreSQL pg_stat_statements, MySQL slow_log).

Monitor DB CPU and I/O wait times.

Look for high-latency spans in distributed tracing (Jaeger, Honeycomb).

Run 'EXPLAIN ANALYZE' on the targeted query.

Look for Sequential Scans on large tables.

Check for missing indexes or outdated table statistics.

Add missing indexes (B-tree, GIN, Hash).

Rewrite subqueries to JOINs where applicable.

Use connection pooling (PgBouncer, HikariCP) to reduce overhead.

PostgreSQL: Show Top Slow Queries

SELECT query, calls, total_time, rows FROM pg_stat_statements ORDER BY total_time DESC LIMIT 10;

MySQL: Analyze Query Execution

EXPLAIN FORMAT=JSON SELECT * FROM users WHERE active = 1;

Check Table Bloat (Postgres)

SELECT relname, n_dead_tup, last_vacuum FROM pg_stat_user_tables;