SQL Server：如何使服务器检查所有的检查约束？

Question

似乎一些由Enterprise Manager生成的脚本（或者不是，这并不重要）创建了WITH NOCHECK的检查约束。

现在，当任何人修改表时，SQL Server会遇到失败的检查约束并抛出错误。

我是否可以让SQL遍历所有的检查约束，并对它们进行检查？

运行：

sp_msforeachtable 'ALTER TABLE ? CHECK CONSTRAINT all'

仅启用先前被禁用的检查约束，实际上并不检查它们。

脚注

* SQL Server 2000

- Ian Boyd

Answer 1

DBCC CHECKCONSTRAINTS WITH ALL_CONSTRAINTS实际上不会使您的约束条件获得信任。它将报告违反约束条件的任何行。要使所有约束条件真正受信任，您可以执行以下操作：

DBCC CHECKCONSTRAINTS WITH ALL_CONSTRAINTS --This reports any data that violates constraints.

--This reports all constraints that are not trusted
SELECT OBJECT_NAME(parent_object_id) AS table_name, name, is_disabled  
FROM sys.check_constraints 
WHERE is_not_trusted = 1
UNION ALL
SELECT OBJECT_NAME(parent_object_id) AS table_name, name, is_disabled  
FROM sys.foreign_keys
WHERE is_not_trusted = 1
ORDER BY table_name

在 SQL Server 2000 中，您可以使用以下代码查找任何不受信任的约束：

--Reports all constraints that are not trusted (SQL 2000)
SELECT name, type, status,
    (status & 2048) AS IsTrusted,
    (status & 256) AS IsEnabled,
    OBJECTPROPERTY(id,'CnstIsNotTrusted') as is_not_trusted,
    OBJECTPROPERTY(id,'CnstIsDisabled') as is_disabled
FROM sysobjects 
WHERE type IN ('C', 'F') --C=Constraint, F=Foreign Key
AND OBJECTPROPERTY(id,'CnstIsNotTrusted') <> 0
AND OBJECTPROPERTY(id,'CnstIsDisabled') = 0

然后使用check重新启用了约束条件:

--This makes all constraints trusted
-- but first anything reported by DBCC CHECKCONSTRAINTS WITH ALL_CONSTRAINTS must be fixed.
exec sp_msforeachtable 'ALTER TABLE ? WITH CHECK CHECK CONSTRAINT all'

注意: 在最后一个语句中，WITH CHECK CHECK不是笔误。"WITH CHECK"将检查所有表数据以确保没有违规行为，并使约束受信任，而"CHECK"将确保启用约束。

另见： http://sqlblog.com/blogs/tibor_karaszi/archive/2008/01/12/non-trusted-constraints.aspx

http://sqlblog.com/blogs/tibor_karaszi/archive/2008/01/12/non-trusted-constraints-and-performance.aspx

- Nathan

Answer 2

找到它了：

检查当前数据库中所有表的所有约束，无论约束是否启用：

DBCC CHECKCONSTRAINTS WITH ALL_CONSTRAINTS

仅检查启用的约束：

DBCC CHECKCONSTRAINTS

- Ian Boyd

Answer 3

请执行以下操作：

ALTER TABLE dbo.Test
      WITH CHECK CHECK CONSTRAINT CK_Test;

解释: 你能相信你的约束条件吗？

- A-K