feat(F-177): completed feature

project/migrations/051_order_state_changed_at.js

@@ -0,0 +1,28 @@
+/** @param {import('node-pg-migrate').MigrationBuilder} pgm */
+exports.shorthands = undefined;
+
+exports.up = (pgm) => {
+  pgm.sql(`
+    ALTER TABLE orders_orders
+    ADD COLUMN IF NOT EXISTS state_changed_at timestamptz;
+
+    UPDATE orders_orders
+    SET state_changed_at = updated_at
+    WHERE state_changed_at IS NULL;
+
+    ALTER TABLE orders_orders
+    ALTER COLUMN state_changed_at SET DEFAULT now(),
+    ALTER COLUMN state_changed_at SET NOT NULL;
+
+    CREATE INDEX IF NOT EXISTS orders_orders_stale_state_idx
+    ON orders_orders (state, state_changed_at)
+    WHERE state IN ('PENDING', 'SHIPPED');
+  `);
+};
+
+exports.down = (pgm) => {
+  pgm.sql(`
+    DROP INDEX IF EXISTS orders_orders_stale_state_idx;
+    ALTER TABLE orders_orders DROP COLUMN IF EXISTS state_changed_at;
+  `);
+};