Suppose we have the usual order & order line item entities: CREATE TABLE "order" ( id INT PRIMARY KEY, date DATE NOT NULL );
CREATE TABLE orderlineitem ( id INT PRIMARY KEY, orderid INT REFERENCES "order"(id), seq INT NOT NULL, CONSTRAINT con1 UNIQUE (orderid, seq), productid INT NOT NULL, quantity INT NOT NULL, price NUMERIC(18,4) NOT NULL ); how do we enforce things like, for example: a) each order must contain at least 1 line item; or b) each order must have a non-zero total value; without making INSERT painful? I'm new to triggers, so I'm thinking of something like a "before COMMIT" trigger but there's no such thing apparently. Regards, dave ---------------------------(end of broadcast)--------------------------- TIP 5: don't forget to increase your free space map settings
