Files uploaded

Lesson08/Exercise32/Trigger.sql

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+DROP FUNCTION update_stock;
+CREATE FUNCTION update_stock() RETURNS TRIGGER AS $stock_trigger$
+DECLARE
+    stock_qty integer;
+BEGIN
+    stock_qty := get_stock(NEW.product_code) - NEW.qty;
+    UPDATE products SET stock = stock_qty WHERE product_code=NEW.product_code; 
+    RETURN NEW;
+END; $stock_trigger$
+LANGUAGE PLPGSQL;
+
+CREATE TRIGGER update_trigger
+AFTER INSERT ON order_info
+FOR EACH ROW
+    EXECUTE PROCEDURE update_stock();