是否可以在已经具有唯一非聚集索引的表中添加主键?
我有一个表 cargo_car,我需要将 cd_cargo_car 定义为 PK。
我试过这个:
ALTER TABLE dbo.cargo_car ADD PRIMARY KEY (cd_cargo_car)
但我收到了错误:
Error (1921) An index with the same columns inthe same order alredy exists onthe table
该表有很多依赖项,当我尝试删除收到的索引时:
Error (3712) Cannot drop index 'cargo_car.XPKcargo_car' because it still has referential integrity constraints.
这是创建脚本:
CREATE TABLE dbo.cargo_car
(
cd_cargo_car SMALLINT NOT NULL,
nm_cargo_car VARCHAR (40) NOT NULL,
cd_refini_car CHAR (4) NOT NULL,
cd_reffin_car CHAR (4) NOT NULL,
cd_jornada1_car CHAR (2) NOT NULL,
cd_jornada2_car CHAR (2) NOT NULL
)
GO
CREATE UNIQUE NONCLUSTERED INDEX XPKcargo_car
ON dbo.cargo_car (cd_cargo_car)
GO
关于如何做到这一点的建议?
Tks