Question

嗨，任何人都可以告诉我如何检查表中是否存在主键，如果不是exql，则在sql server compact（.sdf）中添加主键。

我正在使用它，

  IF NOT EXISTS(SELECT * FROM INFORMATION_SCHEMA.TABLE_CONSTRAINTS WHERE CONSTRAINT_TYPE = 'PRIMARY KEY') 
   BEGIN 
       alter table [tablename] add constraint [name] PRIMARY KEY (columnname)
   END

当我在sql server compact中执行此操作时，我收到此错误..

重大错误0x80040E14，轻微错误25501

IF NOT EXISTS（SELECT * FROM INFORMATION_SCHEMA.TABLE_CONSTRAINTS WHERE CONSTRAINT_TYPE ='PRIMARY KEY'）BEGIN alter table [tablename] add constraint [name] PRIMARY KEY（columnname）END 解析查询时出错。 [令牌行号= 1，令牌行偏移= 1，令牌错误= IF]

谢谢..

Answer 1

 IF NOT EXISTS(SELECT * FROM sys.objects WHERE object_id = OBJECT_ID(N'PRIMARY KEY') AND type in (N'U') )
   BEGIN 
       alter table [tablename] add constraint [PRIMARY KEY] PRIMARY KEY CLUSTERED (columnname)
   END

请使用上述查询，如果有效，请告诉我。感谢。

如何检查和更改约束

1 个答案: