supabase-performance-tuning

# Supabase Performance Tuning ## Overview Systematically improve Supabase query and database performance across three layers: PostgreSQL engine (indexes, query plans, materialized views), Supabase infrastructure (Supavisor connection pooling, Edge Functions, read replicas), and client SDK patterns (column selection, pagination, RPC functions). Every technique here is measurable — run `EXPLAIN ANALYZE` before and after to confirm the improvement. ## Prerequisites - Supabase project (local or hosted) with `@supabase/supabase-js` v2+ installed - Supabase CLI installed (`npx supabase --version` to verify) - Access to the SQL Editor in the Supabase Dashboard or a direct Postgres connection - `pg_stat_statements` extension enabled (Step 1 covers this) ## Instructions ### Step 1: Diagnose — Find What Is Slow Start every performance effort with data. Enable `pg_stat_statements` and run the Supabase CLI diagnostics to identify bottlenecks before optimizing. **Enable the stats extension:** ```sql CREATE EXTENSION IF NOT EXISTS pg_stat_statements; ``` **Find the slowest queries by average execution time:** ```sql SELECT query, calls, mean_exec_time::numeric(10,2) AS avg_ms, total_exec_time::numeric(10,2) AS total_ms, rows FROM pg_stat_statements ORDER BY mean_exec_time DESC LIMIT 10; ``` **Check index usage and cache hit rates with the Supabase CLI:** ```bash # Which indexes are actually being used? npx supabase inspect db index-usage # What percentage of queries...