tRPC & TanStack Query v5 Type Safety

-- 1. Identify slow sequential scans and buffer hits
EXPLAIN (ANALYZE, BUFFERS, SETTINGS)
SELECT id, user_id, amount_cents, created_at
FROM transactions
WHERE tenant_id = 'org_7a9f82'
  AND status = 'pending'
  AND created_at >= NOW() - INTERVAL '30 days'
ORDER BY created_at DESC
LIMIT 50;

-- 2. High-performance covering composite index with partial filter
-- Eliminates heap lookups completely via Index-Only Scans
CREATE INDEX CONCURRENTLY idx_transactions_tenant_pending
ON transactions (tenant_id, created_at DESC)
INCLUDE (id, user_id, amount_cents)
WHERE status = 'pending';

-- 3. Tune connection pooling & autovacuum for high write throughput
ALTER TABLE transactions SET (
  autovacuum_vacuum_scale_factor = 0.05,
  autovacuum_analyze_scale_factor = 0.02,
  autovacuum_vacuum_cost_limit = 1000
);