用SQL语句快速添加约束是怎样添加?

CONSTRAINT 用法

/*例5-11 建立一个SC表，定义SNO,CNO为SC的外部键。*/
/*程序清单如下：*/

Use db
CREATE TABLE SC
(SNO CHAR(10) NOT NULL
CONSTRAINT S_FORE FOREIGN KEY REFERENCES S(SNO),
CNO CHAR(10) NOT NULL
CONSTRAINT C_FORE FOREIGN KEY REFERENCES C(CNO),
SCORE NUMERIC(3),
CONSTRAINT S_C_PRIM PRIMARY KEY (SNO,CNO))