SQL中添加约束的语句

---添加主键约束    
Alter Table stuInfo    
Add Constraint  PK_stuNO primary Key(stuNo)    
---添加唯一约束    
Alter Table stuInfo    
Add Constraint UQ_stuID unique(stuID)    
---添加默认约束    
Alter Table stuInfo    
Add Constraint DF_stuAddress default('地址不详') for stuAddress    
---添加检查约束    
Alter Table stuInfo    
Add Constraint CK_stuAge check(stuAge between 15 and 40)    
---添加外键约束    
Alter Table stuMarks    
Add Constraint FK_stuNo foreign key(stuNo) references stuInfo(stuNo)