unfinished purchase

internal/database/migrations/20251104084540_purchase-items.up.sql

@@ -0,0 +1,59 @@
+CREATE TABLE IF NOT EXISTS purchase_items (
+    id BIGSERIAL PRIMARY KEY,
+    purchase_id BIGINT NOT NULL,
+    product_id BIGINT NOT NULL,
+    warehouse_id BIGINT NOT NULL,
+    product_warehouse_id BIGINT,
+    received_date TIMESTAMPTZ,
+    travel_number VARCHAR,
+    travel_number_docs VARCHAR,
+    vehicle_number VARCHAR,
+    sub_qty NUMERIC(15, 3) NOT NULL,
+    total_qty NUMERIC(15, 3) DEFAULT 0,
+    total_used NUMERIC(15, 3) DEFAULT 0,
+    price NUMERIC(15, 3) DEFAULT 0,
+    total_price NUMERIC(15, 3) DEFAULT 0,
+    created_at TIMESTAMPTZ DEFAULT NOW(),
+    updated_at TIMESTAMPTZ DEFAULT NOW(),
+    deleted_at TIMESTAMPTZ
+);
+
+DO $$
+BEGIN
+    IF EXISTS (SELECT 1 FROM pg_tables WHERE tablename = 'products') THEN
+        EXECUTE
+        'ALTER TABLE purchase_items
+         ADD CONSTRAINT fk_purchase_items_product
+         FOREIGN KEY (product_id)
+         REFERENCES products(id)
+         ON DELETE RESTRICT ON UPDATE CASCADE';
+    END IF;
+
+    IF EXISTS (SELECT 1 FROM pg_tables WHERE tablename = 'warehouses') THEN
+        EXECUTE
+        'ALTER TABLE purchase_items
+         ADD CONSTRAINT fk_purchase_items_warehouse
+         FOREIGN KEY (warehouse_id)
+         REFERENCES warehouses(id)
+         ON DELETE RESTRICT ON UPDATE CASCADE';
+    END IF;
+
+    IF EXISTS (SELECT 1 FROM pg_tables WHERE tablename = 'product_warehouses') THEN
+        EXECUTE
+        'ALTER TABLE purchase_items
+         ADD CONSTRAINT fk_purchase_items_product_warehouse
+         FOREIGN KEY (product_warehouse_id)
+         REFERENCES product_warehouses(id)
+         ON DELETE SET NULL ON UPDATE CASCADE';
+    END IF;
+END $$;
+
+CREATE UNIQUE INDEX IF NOT EXISTS idx_purchase_items_unique_allocation
+    ON purchase_items (purchase_id, product_id, warehouse_id)
+    WHERE deleted_at IS NULL;
+
+CREATE INDEX IF NOT EXISTS idx_purchase_items_product_id ON purchase_items (product_id);
+CREATE INDEX IF NOT EXISTS idx_purchase_items_warehouse_id ON purchase_items (warehouse_id);
+CREATE INDEX IF NOT EXISTS idx_purchase_items_product_warehouse_id ON purchase_items (product_warehouse_id);
+CREATE INDEX IF NOT EXISTS idx_purchase_items_purchase_id ON purchase_items (purchase_id);
+CREATE INDEX IF NOT EXISTS idx_purchase_items_deleted_at ON purchase_items (deleted_at);