alter table tb
add CONSTRAINT [PK_DutyDetail] PRIMARY KEY CLUSTERED
([ID] ASC)
 WITH( PAD_INDEX = OFF, IGNORE_DUP_KEY = OFF) ON [PRIMARY]
 ) ON [PRIMARY]

------解决方案--------------------

SQL code

--sql中为表加约束的sql语句收藏 --为表userinfo的loginName列加唯一约束 

alter table userinfo 

add constraint UQ_loginName unique(loginName) 

--为表userinfo的loginName列加主键约束 

alter table userinfo 

add constraint PK_loginName primary key(loginName) 

--为表userinfo的age列添加检查约束 

alter table userinfo 

add constraint CK_age check(age between 0 and 100) 

--为表userinfo的address列添加默认约束 

alter table userinfo 

add constraint DF_address default('地址不详') for address 

--为表userinfo的classId添加对应classinfo表的classId主键的外键 

alter table userinfo 

add constraint PK_classId foreign key(classId) references classinfo(classId) 

--创建聚集索引 

create clustered index Idx_Area_ID on Company(Area_ID) 

--创建唯一聚集索引 

create unique clustered index Idx_Un_Area_ID on Company(Area_ID) 

--创建非聚集索引 

create nonclustered index Idx_Area_ID on Company(Area_ID) 

--删除约束 

if exists(select * from sys.default_constraints where name='DF_address' and parent_object_id=object_id('userinfo')) 

begin 

alter table userinfo drop constraint DF_address 

end