Initial commit - Church Music Database

legacy-site/backend/optimize_database.sql

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+-- Database Optimization Script
+-- Date: January 4, 2026
+-- Purpose: Remove redundant indexes, optimize queries, improve performance
+
+-- ============================================
+-- STEP 1: Remove Redundant Indexes
+-- ============================================
+
+-- Remove duplicate index on profile_song_keys
+-- Keep: uq_profile_song_key (unique constraint)
+-- Keep: idx_profile_song_keys (for lookups)
+-- Remove: idx_profile_keys (exact duplicate)
+DROP INDEX IF EXISTS idx_profile_keys;
+
+-- Remove redundant single-column index on plan_songs
+-- Keep: idx_plan_songs_order (composite index: plan_id, order_index)
+-- Remove: idx_plan_songs_plan (redundant - composite index handles this)
+DROP INDEX IF EXISTS idx_plan_songs_plan;
+
+-- ============================================
+-- STEP 2: Optimize Low-Cardinality Indexes
+-- ============================================
+
+-- Replace full index on users.active with partial index
+-- Most users are active, so only index the exceptions
+DROP INDEX IF EXISTS idx_user_active;
+CREATE INDEX IF NOT EXISTS idx_user_inactive ON users (id) WHERE active = false;
+
+-- ============================================
+-- STEP 3: Add Composite Indexes for Common Queries
+-- ============================================
+
+-- Optimize query: "find plans by profile within date range"
+CREATE INDEX IF NOT EXISTS idx_plan_profile_date ON plans (profile_id, date) 
+WHERE profile_id IS NOT NULL;
+
+-- Add index for plan song lookups (if not exists)
+CREATE INDEX IF NOT EXISTS idx_plan_songs_song ON plan_songs (song_id);
+
+-- Add index for profile song reverse lookups (if not exists)
+CREATE INDEX IF NOT EXISTS idx_profile_songs_song ON profile_songs (song_id);
+
+-- ============================================
+-- STEP 4: Verify Index Effectiveness
+-- ============================================
+
+-- Show all indexes after cleanup
+SELECT 
+    schemaname,
+    tablename,
+    indexname,
+    indexdef
+FROM pg_indexes 
+WHERE schemaname = 'public'
+ORDER BY tablename, indexname;
+
+-- Show index sizes
+SELECT
+    schemaname,
+    tablename,
+    indexname,
+    pg_size_pretty(pg_relation_size(indexrelid)) as index_size
+FROM pg_stat_user_indexes
+WHERE schemaname = 'public'
+ORDER BY pg_relation_size(indexrelid) DESC;
+
+-- ============================================
+-- STEP 5: Analyze Tables for Query Planner
+-- ============================================
+
+-- Update statistics for query planner optimization
+ANALYZE users;
+ANALYZE profiles;
+ANALYZE songs;
+ANALYZE plans;
+ANALYZE plan_songs;
+ANALYZE profile_songs;
+ANALYZE profile_song_keys;
+ANALYZE biometric_credentials;
+
+-- ============================================
+-- VERIFICATION QUERIES
+-- ============================================
+
+-- Check for unused indexes (run after a week of production use)
+-- SELECT 
+--     schemaname,
+--     tablename,
+--     indexname,
+--     idx_scan as scans,
+--     pg_size_pretty(pg_relation_size(indexrelid)) as size
+-- FROM pg_stat_user_indexes
+-- WHERE schemaname = 'public'
+-- AND idx_scan = 0
+-- AND indexrelid IS NOT NULL
+-- ORDER BY pg_relation_size(indexrelid) DESC;
+
+-- Check for missing indexes on foreign keys
+-- SELECT 
+--     c.conname AS constraint_name,
+--     t.relname AS table_name,
+--     ARRAY_AGG(a.attname ORDER BY u.attposition) AS columns
+-- FROM pg_constraint c
+-- JOIN pg_class t ON c.conrelid = t.oid
+-- JOIN pg_namespace n ON t.relnamespace = n.oid
+-- JOIN LATERAL UNNEST(c.conkey) WITH ORDINALITY AS u(attnum, attposition) ON TRUE
+-- JOIN pg_attribute a ON a.attrelid = t.oid AND a.attnum = u.attnum
+-- WHERE c.contype = 'f'
+-- AND n.nspname = 'public'
+-- GROUP BY c.conname, t.relname;
+
+COMMIT;