sql server创建复合主键的2种方法
sql server创建复合主键的2种方法，需要的朋友可以参考一下
创建复合主键：方法一：创建表之后，alter table table_name add primary key(字段1，字段2)
方法二：CREATE TABLE 表名 (字段名1 Int Not Null,
字段名2 nvarchar(13) Not Null
字段名3…………
字段名N…………)
GO
ALTER TABLE 表名 WITH NOCHECK ADD
CONSTRAINT [PK_表名] PRIMARY KEY NONCLUSTERED
(
[字段名1],
[字段名2]
)
GO
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