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+---
+title: Enable pg_stat_statements for Query Analysis
+impact: LOW-MEDIUM
+impactDescription: Identify top resource-consuming queries
+tags: pg-stat-statements, monitoring, statistics, performance
+---
+
+## Enable pg_stat_statements for Query Analysis
+
+pg_stat_statements tracks execution statistics for all queries, helping identify slow and frequent queries.
+
+**Incorrect (no visibility into query patterns):**
+
+```sql
+-- Database is slow, but which queries are the problem?
+-- No way to know without pg_stat_statements
+```
+
+**Correct (enable and query pg_stat_statements):**
+
+```sql
+-- Enable the extension
+create extension if not exists pg_stat_statements;
+
+-- Find slowest queries by total time
+select
+  calls,
+  round(total_exec_time::numeric, 2) as total_time_ms,
+  round(mean_exec_time::numeric, 2) as mean_time_ms,
+  query
+from pg_stat_statements
+order by total_exec_time desc
+limit 10;
+
+-- Find most frequent queries
+select calls, query
+from pg_stat_statements
+order by calls desc
+limit 10;
+
+-- Reset statistics after optimization
+select pg_stat_statements_reset();
+```
+
+Key metrics to monitor:
+
+```sql
+-- Queries with high mean time (candidates for optimization)
+select query, mean_exec_time, calls
+from pg_stat_statements
+where mean_exec_time > 100  -- > 100ms average
+order by mean_exec_time desc;
+```
+
+Reference: [pg_stat_statements](https://supabase.com/docs/guides/database/extensions/pg_stat_statements)