CREATE TABLE DeliveryItem (
DeliveryItemID smallint NOT NULL,
DeliveryID smallint NOT NULL,
OrderItemID smallint NOT NULL,
Received smallint NOT NULL,
CONSTRAINT PKDIID PRIMARY KEY (DeliveryItemID),
CONSTRAINT FKDLRYID FOREIGN KEY (DeliveryID)
REFERENCES delivery(deliveryid),
CONSTRAINT FKOIID FOREIGN KEY (OrderItemID)REFERENCES
orderitem(orderitemid),
CONSTRAINT UKRECEIVED UNIQUE (Received)
);这个表中对字段Received定义了唯一性约束
所以插入两条Received=30或者20的记录就违反了唯一性约束限制。
DeliveryItemID smallint NOT NULL,
DeliveryID smallint NOT NULL,
OrderItemID smallint NOT NULL,
Received smallint NOT NULL,
CONSTRAINT PKDIID PRIMARY KEY (DeliveryItemID),
CONSTRAINT FKDLRYID FOREIGN KEY (DeliveryID)
REFERENCES delivery(deliveryid),
CONSTRAINT FKOIID FOREIGN KEY (OrderItemID)REFERENCES
orderitem(orderitemid),
CONSTRAINT UKRECEIVED UNIQUE (Received)
);这个表中对字段Received定义了唯一性约束
所以插入两条Received=30或者20的记录就违反了唯一性约束限制。
解决方案 »
免费领取超大流量手机卡,每月29元包185G流量+100分钟通话, 中国电信官方发货