如何使用T-SQL临时禁用外键约束?

时间:2008-10-01 18:33:44

标签: sql-server tsql foreign-keys constraints

是否禁用和启用SQL Server中支持的外键约束?或者我是唯一选择 drop 然后重新create 约束?

16 个答案:

答案 0 :(得分:1068)

如果要禁用数据库中的所有约束,只需运行以下代码:

-- disable all constraints
EXEC sp_MSforeachtable "ALTER TABLE ? NOCHECK CONSTRAINT all"

要重新打开它们,请运行:(打印是可选的,当然只是列出表格)

-- enable all constraints
exec sp_MSforeachtable @command1="print '?'", @command2="ALTER TABLE ? WITH CHECK CHECK CONSTRAINT all"

我发现将数据从一个数据库填充到另一个数据库时很有用。这比删除约束要好得多。正如您所提到的,在将所有数据放入数据库并重新填充数据库时(例如在测试环境中),它非常方便。

如果要删除所有数据,可能会发现this solution有用。

有时候禁用所有触发器也很方便,你可以看到完整的解决方案here

答案 1 :(得分:377)

http://www.sqljunkies.com/WebLog/roman/archive/2005/01/30/7037.aspx

-- Disable all table constraints

ALTER TABLE MyTable NOCHECK CONSTRAINT ALL

-- Enable all table constraints

ALTER TABLE MyTable WITH CHECK CHECK CONSTRAINT ALL

-- Disable single constraint

ALTER TABLE MyTable NOCHECK CONSTRAINT MyConstraint

-- Enable single constraint

ALTER TABLE MyTable WITH CHECK CHECK CONSTRAINT MyConstraint

答案 2 :(得分:28)

要禁用约束,请使用NOCHECK

更改表格
ALTER TABLE [TABLE_NAME] NOCHECK CONSTRAINT [ALL|CONSTRAINT_NAME]

要启用,您必须使用双CHECK

ALTER TABLE [TABLE_NAME] WITH CHECK CHECK CONSTRAINT [ALL|CONSTRAINT_NAME]
  • 启用时请注意双检查检查
  • ALL表示表格中的所有约束。

完成后,如果需要检查状态,请使用此脚本列出约束状态。非常有帮助:

    SELECT (CASE 
        WHEN OBJECTPROPERTY(CONSTID, 'CNSTISDISABLED') = 0 THEN 'ENABLED'
        ELSE 'DISABLED'
        END) AS STATUS,
        OBJECT_NAME(CONSTID) AS CONSTRAINT_NAME,
        OBJECT_NAME(FKEYID) AS TABLE_NAME,
        COL_NAME(FKEYID, FKEY) AS COLUMN_NAME,
        OBJECT_NAME(RKEYID) AS REFERENCED_TABLE_NAME,
        COL_NAME(RKEYID, RKEY) AS REFERENCED_COLUMN_NAME
   FROM SYSFOREIGNKEYS
ORDER BY TABLE_NAME, CONSTRAINT_NAME,REFERENCED_TABLE_NAME, KEYNO 

答案 3 :(得分:27)

您最好的选择是DROP和CREATE外键约束。

我在这篇文章中没有找到可以“按原样”为我工作的例子,如果外键引用不同的模式,则无法工作,如果外键引用多个列,则另一个不起作用。此脚本同时考虑每个外键的多个模式和多个列。

这是生成“ADD CONSTRAINT”语句的脚本,对于多个列,它将用逗号分隔它们(确保在执行DROP语句之前保存此输出):

PRINT N'-- CREATE FOREIGN KEY CONSTRAINTS --';

SET NOCOUNT ON;
SELECT '
PRINT N''Creating '+ const.const_name +'...''
GO
ALTER TABLE ' + const.parent_obj + '
    ADD CONSTRAINT ' + const.const_name + ' FOREIGN KEY (
            ' + const.parent_col_csv + '
            ) REFERENCES ' + const.ref_obj + '(' + const.ref_col_csv + ')
GO'
FROM (
    SELECT QUOTENAME(fk.NAME) AS [const_name]
        ,QUOTENAME(schParent.NAME) + '.' + QUOTENAME(OBJECT_name(fkc.parent_object_id)) AS [parent_obj]
        ,STUFF((
                SELECT ',' + QUOTENAME(COL_NAME(fcP.parent_object_id, fcp.parent_column_id))
                FROM sys.foreign_key_columns AS fcP
                WHERE fcp.constraint_object_id = fk.object_id
                FOR XML path('')
                ), 1, 1, '') AS [parent_col_csv]
        ,QUOTENAME(schRef.NAME) + '.' + QUOTENAME(OBJECT_NAME(fkc.referenced_object_id)) AS [ref_obj]
        ,STUFF((
                SELECT ',' + QUOTENAME(COL_NAME(fcR.referenced_object_id, fcR.referenced_column_id))
                FROM sys.foreign_key_columns AS fcR
                WHERE fcR.constraint_object_id = fk.object_id
                FOR XML path('')
                ), 1, 1, '') AS [ref_col_csv]
    FROM sys.foreign_key_columns AS fkc
    INNER JOIN sys.foreign_keys AS fk ON fk.object_id = fkc.constraint_object_id
    INNER JOIN sys.objects AS oParent ON oParent.object_id = fkc.parent_object_id
    INNER JOIN sys.schemas AS schParent ON schParent.schema_id = oParent.schema_id
    INNER JOIN sys.objects AS oRef ON oRef.object_id = fkc.referenced_object_id
    INNER JOIN sys.schemas AS schRef ON schRef.schema_id = oRef.schema_id
    GROUP BY fkc.parent_object_id
        ,fkc.referenced_object_id
        ,fk.NAME
        ,fk.object_id
        ,schParent.NAME
        ,schRef.NAME
    ) AS const
ORDER BY const.const_name

以下是生成“DROP CONSTRAINT”语句的脚本:

PRINT N'-- DROP FOREIGN KEY CONSTRAINTS --';

SET NOCOUNT ON;

SELECT '
PRINT N''Dropping ' + fk.NAME + '...''
GO
ALTER TABLE [' + sch.NAME + '].[' + OBJECT_NAME(fk.parent_object_id) + ']' + ' DROP  CONSTRAINT ' + '[' + fk.NAME + ']
GO'
FROM sys.foreign_keys AS fk
INNER JOIN sys.schemas AS sch ON sch.schema_id = fk.schema_id
ORDER BY fk.NAME

答案 4 :(得分:9)

SQL-92标准允许将constaint声明为DEFERRABLE,以便可以在事务范围内延迟(隐式或显式)。遗憾的是,SQL Server仍然缺少这种SQL-92功能。

对我来说,将约束更改为NOCHECK类似于动态更改数据库结构 - 当然是删除约束 - 并且需要避免的事情(例如用户需要增加的权限)。

答案 5 :(得分:9)

   --Drop and Recreate Foreign Key Constraints

SET NOCOUNT ON

DECLARE @table TABLE(
   RowId INT PRIMARY KEY IDENTITY(1, 1),
   ForeignKeyConstraintName NVARCHAR(200),
   ForeignKeyConstraintTableSchema NVARCHAR(200),
   ForeignKeyConstraintTableName NVARCHAR(200),
   ForeignKeyConstraintColumnName NVARCHAR(200),
   PrimaryKeyConstraintName NVARCHAR(200),
   PrimaryKeyConstraintTableSchema NVARCHAR(200),
   PrimaryKeyConstraintTableName NVARCHAR(200),
   PrimaryKeyConstraintColumnName NVARCHAR(200)    
)

INSERT INTO @table(ForeignKeyConstraintName, ForeignKeyConstraintTableSchema, ForeignKeyConstraintTableName, ForeignKeyConstraintColumnName)
SELECT 
   U.CONSTRAINT_NAME, 
   U.TABLE_SCHEMA, 
   U.TABLE_NAME, 
   U.COLUMN_NAME 
FROM 
   INFORMATION_SCHEMA.KEY_COLUMN_USAGE U
      INNER JOIN INFORMATION_SCHEMA.TABLE_CONSTRAINTS C
         ON U.CONSTRAINT_NAME = C.CONSTRAINT_NAME
WHERE
   C.CONSTRAINT_TYPE = 'FOREIGN KEY'

UPDATE @table SET
   PrimaryKeyConstraintName = UNIQUE_CONSTRAINT_NAME
FROM 
   @table T
      INNER JOIN INFORMATION_SCHEMA.REFERENTIAL_CONSTRAINTS R
         ON T.ForeignKeyConstraintName = R.CONSTRAINT_NAME

UPDATE @table SET
   PrimaryKeyConstraintTableSchema  = TABLE_SCHEMA,
   PrimaryKeyConstraintTableName  = TABLE_NAME
FROM @table T
   INNER JOIN INFORMATION_SCHEMA.TABLE_CONSTRAINTS C
      ON T.PrimaryKeyConstraintName = C.CONSTRAINT_NAME

UPDATE @table SET
   PrimaryKeyConstraintColumnName = COLUMN_NAME
FROM @table T
   INNER JOIN INFORMATION_SCHEMA.KEY_COLUMN_USAGE U
      ON T.PrimaryKeyConstraintName = U.CONSTRAINT_NAME

--SELECT * FROM @table

--DROP CONSTRAINT:
SELECT
   '
   ALTER TABLE [' + ForeignKeyConstraintTableSchema + '].[' + ForeignKeyConstraintTableName + '] 
   DROP CONSTRAINT ' + ForeignKeyConstraintName + '

   GO'
FROM
   @table

--ADD CONSTRAINT:
SELECT
   '
   ALTER TABLE [' + ForeignKeyConstraintTableSchema + '].[' + ForeignKeyConstraintTableName + '] 
   ADD CONSTRAINT ' + ForeignKeyConstraintName + ' FOREIGN KEY(' + ForeignKeyConstraintColumnName + ') REFERENCES [' + PrimaryKeyConstraintTableSchema + '].[' + PrimaryKeyConstraintTableName + '](' + PrimaryKeyConstraintColumnName + ')

   GO'
FROM
   @table

GO

我同意你的看法,哈姆林。当您使用SSIS传输数据或想要复制数据时,似乎必须暂时禁用或删除外键约束,然后重新启用或重新创建它们。在这些情况下,引用完整性不是问题,因为它已在源数据库中维护。因此,您可以放心这件事。

答案 6 :(得分:9)

SET NOCOUNT ON

DECLARE @table TABLE(
   RowId INT PRIMARY KEY IDENTITY(1, 1),
   ForeignKeyConstraintName NVARCHAR(200),
   ForeignKeyConstraintTableSchema NVARCHAR(200),
   ForeignKeyConstraintTableName NVARCHAR(200),
   ForeignKeyConstraintColumnName NVARCHAR(200),
   PrimaryKeyConstraintName NVARCHAR(200),
   PrimaryKeyConstraintTableSchema NVARCHAR(200),
   PrimaryKeyConstraintTableName NVARCHAR(200),
   PrimaryKeyConstraintColumnName NVARCHAR(200),
   UpdateRule NVARCHAR(100),
   DeleteRule NVARCHAR(100)   
)

INSERT INTO @table(ForeignKeyConstraintName, ForeignKeyConstraintTableSchema, ForeignKeyConstraintTableName, ForeignKeyConstraintColumnName)
SELECT 
   U.CONSTRAINT_NAME, 
   U.TABLE_SCHEMA, 
   U.TABLE_NAME, 
   U.COLUMN_NAME
FROM 
   INFORMATION_SCHEMA.KEY_COLUMN_USAGE U
      INNER JOIN INFORMATION_SCHEMA.TABLE_CONSTRAINTS C
         ON U.CONSTRAINT_NAME = C.CONSTRAINT_NAME
WHERE
   C.CONSTRAINT_TYPE = 'FOREIGN KEY'

UPDATE @table SET
   T.PrimaryKeyConstraintName = R.UNIQUE_CONSTRAINT_NAME,
   T.UpdateRule = R.UPDATE_RULE,
   T.DeleteRule = R.DELETE_RULE
FROM 
   @table T
      INNER JOIN INFORMATION_SCHEMA.REFERENTIAL_CONSTRAINTS R
         ON T.ForeignKeyConstraintName = R.CONSTRAINT_NAME

UPDATE @table SET
   PrimaryKeyConstraintTableSchema  = TABLE_SCHEMA,
   PrimaryKeyConstraintTableName  = TABLE_NAME
FROM @table T
   INNER JOIN INFORMATION_SCHEMA.TABLE_CONSTRAINTS C
      ON T.PrimaryKeyConstraintName = C.CONSTRAINT_NAME

UPDATE @table SET
   PrimaryKeyConstraintColumnName = COLUMN_NAME
FROM @table T
   INNER JOIN INFORMATION_SCHEMA.KEY_COLUMN_USAGE U
      ON T.PrimaryKeyConstraintName = U.CONSTRAINT_NAME

--SELECT * FROM @table

SELECT '
BEGIN TRANSACTION
BEGIN TRY'

--DROP CONSTRAINT:
SELECT
   '
 ALTER TABLE [' + ForeignKeyConstraintTableSchema + '].[' + ForeignKeyConstraintTableName + '] 
 DROP CONSTRAINT ' + ForeignKeyConstraintName + '
   '
FROM
   @table

SELECT '
END TRY

BEGIN CATCH
   ROLLBACK TRANSACTION
   RAISERROR(''Operation failed.'', 16, 1)
END CATCH

IF(@@TRANCOUNT != 0)
BEGIN
   COMMIT TRANSACTION
   RAISERROR(''Operation completed successfully.'', 10, 1)
END
'

--ADD CONSTRAINT:
SELECT '
BEGIN TRANSACTION
BEGIN TRY'

SELECT
   '
   ALTER TABLE [' + ForeignKeyConstraintTableSchema + '].[' + ForeignKeyConstraintTableName + '] 
   ADD CONSTRAINT ' + ForeignKeyConstraintName + ' FOREIGN KEY(' + ForeignKeyConstraintColumnName + ') REFERENCES [' + PrimaryKeyConstraintTableSchema + '].[' + PrimaryKeyConstraintTableName + '](' + PrimaryKeyConstraintColumnName + ') ON UPDATE ' + UpdateRule + ' ON DELETE ' + DeleteRule + '
   '
FROM
   @table

SELECT '
END TRY

BEGIN CATCH
   ROLLBACK TRANSACTION
   RAISERROR(''Operation failed.'', 16, 1)
END CATCH

IF(@@TRANCOUNT != 0)
BEGIN
   COMMIT TRANSACTION
   RAISERROR(''Operation completed successfully.'', 10, 1)
END'

GO

答案 7 :(得分:7)

第一篇文章:)

对于OP,kristof的解决方案将起作用,除非在大删除上存在大量数据和事务日志气球问题。此外,即使使用tlog存储,由于删除了对tlog的写入操作,对于具有数亿行的表,操作可能需要很长时间。

我使用一系列游标来频繁截断并重新加载我们庞大的生产数据库中的大型副本。该解决方案设计了多个模式,多个外键列,最重要的是可以在SSIS中使用。

它涉及创建三个临时表(实际表)以容纳DROP,CREATE和CHECK FK脚本,创建这些脚本并将其插入表中,然后循环遍历表并执行它们。附加的脚本分为四个部分:1。)在三个临时(实际)表中创建和存储脚本,2。通过游标逐个执行drop FK脚本,3。)使用sp_MSforeachtable截断所有除了我们的三个临时表之外的数据库中的表和4.)执行create FK并检查ETL SSIS包末尾的FK脚本。

在SSIS中的“执行SQL”任务中运行脚本创建部分。在第二个执行SQL任务中运行“execute Drop FK Scripts”部分。将截断脚本放在第三个执行SQL任务中,然后在控制流结束时将CREATE和CHECK脚本附加到最终的执行SQL任务(或两个,如果需要)之前,执行您需要执行的任何其他ETL过程。 / p>

当重新应用外键失败时,实际表中脚本的存储已经证明非常有用,因为您可以从sync_CreateFK中选择*,复制/粘贴到查询窗口,一次运行一个,并修复数据一旦找到失败/仍然无法重新申请的问题。

如果脚本失败而不确保在执行此操作之前重新应用所有外键/检查,请不要再次重新运行脚本,否则您很可能会丢失一些创建并检查fk脚本作为我们的临时表在创建要执行的脚本之前删除并重新创建。

----------------------------------------------------------------------------
1)
/*
Author:         Denmach
DateCreated:    2014-04-23
Purpose:        Generates SQL statements to DROP, ADD, and CHECK existing constraints for a 
                database.  Stores scripts in tables on target database for execution.  Executes
                those stored scripts via independent cursors. 
DateModified:
ModifiedBy
Comments:       This will eliminate deletes and the T-log ballooning associated with it.
*/

DECLARE @schema_name SYSNAME; 
DECLARE @table_name SYSNAME; 
DECLARE @constraint_name SYSNAME; 
DECLARE @constraint_object_id INT; 
DECLARE @referenced_object_name SYSNAME; 
DECLARE @is_disabled BIT; 
DECLARE @is_not_for_replication BIT; 
DECLARE @is_not_trusted BIT; 
DECLARE @delete_referential_action TINYINT; 
DECLARE @update_referential_action TINYINT; 
DECLARE @tsql NVARCHAR(4000); 
DECLARE @tsql2 NVARCHAR(4000); 
DECLARE @fkCol SYSNAME; 
DECLARE @pkCol SYSNAME; 
DECLARE @col1 BIT; 
DECLARE @action CHAR(6);  
DECLARE @referenced_schema_name SYSNAME;



--------------------------------Generate scripts to drop all foreign keys in a database --------------------------------

IF OBJECT_ID('dbo.sync_dropFK') IS NOT NULL
DROP TABLE sync_dropFK

CREATE TABLE sync_dropFK
    (
    ID INT IDENTITY (1,1) NOT NULL
    , Script NVARCHAR(4000)
    )

DECLARE FKcursor CURSOR FOR

    SELECT 
        OBJECT_SCHEMA_NAME(parent_object_id)
        , OBJECT_NAME(parent_object_id)
        , name
    FROM 
        sys.foreign_keys WITH (NOLOCK)
    ORDER BY 
        1,2;

OPEN FKcursor;

FETCH NEXT FROM FKcursor INTO 
    @schema_name
    , @table_name
    , @constraint_name

WHILE @@FETCH_STATUS = 0

BEGIN
        SET @tsql = 'ALTER TABLE '
                + QUOTENAME(@schema_name) 
                + '.' 
                + QUOTENAME(@table_name)
                + ' DROP CONSTRAINT ' 
                + QUOTENAME(@constraint_name) 
                + ';';
    --PRINT @tsql;
    INSERT sync_dropFK  (
                        Script
                        )
                        VALUES (
                                @tsql
                                )   

    FETCH NEXT FROM FKcursor INTO 
    @schema_name
    , @table_name
    , @constraint_name
    ;

END;

CLOSE FKcursor;

DEALLOCATE FKcursor;


---------------Generate scripts to create all existing foreign keys in a database --------------------------------
----------------------------------------------------------------------------------------------------------
IF OBJECT_ID('dbo.sync_createFK') IS NOT NULL
DROP TABLE sync_createFK

CREATE TABLE sync_createFK
    (
    ID INT IDENTITY (1,1) NOT NULL
    , Script NVARCHAR(4000)
    )

IF OBJECT_ID('dbo.sync_createCHECK') IS NOT NULL
DROP TABLE sync_createCHECK

CREATE TABLE sync_createCHECK
    (
    ID INT IDENTITY (1,1) NOT NULL
    , Script NVARCHAR(4000)
    )   

DECLARE FKcursor CURSOR FOR

     SELECT 
        OBJECT_SCHEMA_NAME(parent_object_id)
        , OBJECT_NAME(parent_object_id)
        , name
        , OBJECT_NAME(referenced_object_id)
        , OBJECT_ID
        , is_disabled
        , is_not_for_replication
        , is_not_trusted
        , delete_referential_action
        , update_referential_action
        , OBJECT_SCHEMA_NAME(referenced_object_id)

    FROM 
        sys.foreign_keys WITH (NOLOCK)

    ORDER BY 
        1,2;

OPEN FKcursor;

FETCH NEXT FROM FKcursor INTO 
    @schema_name
    , @table_name
    , @constraint_name
    , @referenced_object_name
    , @constraint_object_id
    , @is_disabled
    , @is_not_for_replication
    , @is_not_trusted
    , @delete_referential_action
    , @update_referential_action
    , @referenced_schema_name;

WHILE @@FETCH_STATUS = 0

BEGIN

        BEGIN
            SET @tsql = 'ALTER TABLE '
                        + QUOTENAME(@schema_name) 
                        + '.' 
                        + QUOTENAME(@table_name)
                        +   CASE 
                                @is_not_trusted
                                WHEN 0 THEN ' WITH CHECK '
                                ELSE ' WITH NOCHECK '
                            END
                        + ' ADD CONSTRAINT ' 
                        + QUOTENAME(@constraint_name)
                        + ' FOREIGN KEY (';

        SET @tsql2 = '';

        DECLARE ColumnCursor CURSOR FOR 

            SELECT 
                COL_NAME(fk.parent_object_id
                , fkc.parent_column_id)
                , COL_NAME(fk.referenced_object_id
                , fkc.referenced_column_id)

            FROM 
                sys.foreign_keys fk WITH (NOLOCK)
                INNER JOIN sys.foreign_key_columns fkc WITH (NOLOCK) ON fk.[object_id] = fkc.constraint_object_id

            WHERE 
                fkc.constraint_object_id = @constraint_object_id

            ORDER BY 
                fkc.constraint_column_id;

        OPEN ColumnCursor;

        SET @col1 = 1;

        FETCH NEXT FROM ColumnCursor INTO @fkCol, @pkCol;

        WHILE @@FETCH_STATUS = 0

        BEGIN
            IF (@col1 = 1)
                SET @col1 = 0;
            ELSE
            BEGIN
                SET @tsql = @tsql + ',';
                SET @tsql2 = @tsql2 + ',';
            END;

            SET @tsql = @tsql + QUOTENAME(@fkCol);
            SET @tsql2 = @tsql2 + QUOTENAME(@pkCol);
            --PRINT '@tsql = ' + @tsql 
            --PRINT '@tsql2 = ' + @tsql2
            FETCH NEXT FROM ColumnCursor INTO @fkCol, @pkCol;
            --PRINT 'FK Column ' + @fkCol
            --PRINT 'PK Column ' + @pkCol 
        END;

        CLOSE ColumnCursor;
        DEALLOCATE ColumnCursor;

        SET @tsql = @tsql + ' ) REFERENCES ' 
                    + QUOTENAME(@referenced_schema_name) 
                    + '.' 
                    + QUOTENAME(@referenced_object_name)
                    + ' (' 
                    + @tsql2 + ')';

        SET @tsql = @tsql
                    + ' ON UPDATE ' 
                    + 
                        CASE @update_referential_action
                            WHEN 0 THEN 'NO ACTION '
                            WHEN 1 THEN 'CASCADE '
                            WHEN 2 THEN 'SET NULL '
                                ELSE 'SET DEFAULT '
                        END

                    + ' ON DELETE ' 
                    + 
                        CASE @delete_referential_action
                            WHEN 0 THEN 'NO ACTION '
                            WHEN 1 THEN 'CASCADE '
                            WHEN 2 THEN 'SET NULL '
                                ELSE 'SET DEFAULT '
                        END

                    + 
                    CASE @is_not_for_replication
                        WHEN 1 THEN ' NOT FOR REPLICATION '
                            ELSE ''
                    END
                    + ';';

        END;

    --  PRINT @tsql
        INSERT sync_createFK    
                        (
                        Script
                        )
                        VALUES (
                                @tsql
                                )

-------------------Generate CHECK CONSTRAINT scripts for a database ------------------------------
----------------------------------------------------------------------------------------------------------

        BEGIN

        SET @tsql = 'ALTER TABLE '
                    + QUOTENAME(@schema_name) 
                    + '.' 
                    + QUOTENAME(@table_name)
                    + 
                        CASE @is_disabled
                            WHEN 0 THEN ' CHECK '
                                ELSE ' NOCHECK '
                        END
                    + 'CONSTRAINT ' 
                    + QUOTENAME(@constraint_name)
                    + ';';
        --PRINT @tsql;
        INSERT sync_createCHECK 
                        (
                        Script
                        )
                        VALUES (
                                @tsql
                                )   
        END;

    FETCH NEXT FROM FKcursor INTO 
    @schema_name
    , @table_name
    , @constraint_name
    , @referenced_object_name
    , @constraint_object_id
    , @is_disabled
    , @is_not_for_replication
    , @is_not_trusted
    , @delete_referential_action
    , @update_referential_action
    , @referenced_schema_name;

END;

CLOSE FKcursor;

DEALLOCATE FKcursor;

--SELECT * FROM sync_DropFK
--SELECT * FROM sync_CreateFK
--SELECT * FROM sync_CreateCHECK
---------------------------------------------------------------------------
2.)
-----------------------------------------------------------------------------------------------------------------
----------------------------execute Drop FK Scripts --------------------------------------------------

DECLARE @scriptD NVARCHAR(4000)

DECLARE DropFKCursor CURSOR FOR
    SELECT Script 
    FROM sync_dropFK WITH (NOLOCK)

OPEN DropFKCursor

FETCH NEXT FROM DropFKCursor
INTO @scriptD

WHILE @@FETCH_STATUS = 0
BEGIN
--PRINT @scriptD
EXEC (@scriptD)
FETCH NEXT FROM DropFKCursor
INTO @scriptD
END
CLOSE DropFKCursor
DEALLOCATE DropFKCursor
--------------------------------------------------------------------------------
3.) 

------------------------------------------------------------------------------------------------------------------
----------------------------Truncate all tables in the database other than our staging tables --------------------
------------------------------------------------------------------------------------------------------------------


EXEC sp_MSforeachtable 'IF OBJECT_ID(''?'') NOT IN 
(
ISNULL(OBJECT_ID(''dbo.sync_createCHECK''),0),
ISNULL(OBJECT_ID(''dbo.sync_createFK''),0),
ISNULL(OBJECT_ID(''dbo.sync_dropFK''),0)
)
BEGIN TRY
 TRUNCATE TABLE ?
END TRY
BEGIN CATCH
 PRINT ''Truncation failed on''+ ? +''
END CATCH;' 
GO
-------------------------------------------------------------------------------
-------------------------------------------------------------------------------------------------
----------------------------execute Create FK Scripts and CHECK CONSTRAINT Scripts---------------
----------------------------tack me at the end of the ETL in a SQL task-------------------------
-------------------------------------------------------------------------------------------------
DECLARE @scriptC NVARCHAR(4000)

DECLARE CreateFKCursor CURSOR FOR
    SELECT Script 
    FROM sync_createFK WITH (NOLOCK)

OPEN CreateFKCursor

FETCH NEXT FROM CreateFKCursor
INTO @scriptC

WHILE @@FETCH_STATUS = 0
BEGIN
--PRINT @scriptC
EXEC (@scriptC)
FETCH NEXT FROM CreateFKCursor
INTO @scriptC
END
CLOSE CreateFKCursor
DEALLOCATE CreateFKCursor
-------------------------------------------------------------------------------------------------
DECLARE @scriptCh NVARCHAR(4000)

DECLARE CreateCHECKCursor CURSOR FOR
    SELECT Script 
    FROM sync_createCHECK WITH (NOLOCK)

OPEN CreateCHECKCursor

FETCH NEXT FROM CreateCHECKCursor
INTO @scriptCh

WHILE @@FETCH_STATUS = 0
BEGIN
--PRINT @scriptCh
EXEC (@scriptCh)
FETCH NEXT FROM CreateCHECKCursor
INTO @scriptCh
END
CLOSE CreateCHECKCursor
DEALLOCATE CreateCHECKCursor

答案 8 :(得分:7)

几乎可以肯定

WITH CHECK CHECK

在一些答案和评论中提出了这一点,但我觉得重新称之为重要。

使用以下命令重新启用约束(无WITH CHECK)将有一些serious drawbacks

ALTER TABLE MyTable CHECK CONSTRAINT MyConstraint;
  

WITH CHECK |没有检查

     

指定是否对表中的数据进行验证   新添加或重新启用的FOREIGN KEY或CHECK约束。如果不   指定,WITH CHECK用于新约束,WITH NOCHECK   假定重新启用约束。

     

如果您不想验证新的CHECK或FOREIGN KEY约束   针对现有数据,使用WITH NOCHECK。我们不建议这样做   这是罕见的情况。新约束将在中进行评估   所有以后的数据更新。任何被抑制的约束违规   通过WITH NOCHECK添加约束可能会导致将来更新   如果他们用不符合的数据更新行,则会失败   约束。

     

查询优化器不考虑已定义的约束   没有检查。在重新启用这些约束之前,将忽略这些约束   通过使用ALTER TABLE表WITH CHECK CHECK CONSTRAINT ALL。

注意: WITH NOCHECK是重新启用约束的默认设置。我不知道为什么......

  1. 在执行此命令期间,不会评估表中的现有数据 - 成功完成并不能保证表中的数据根据​​约束有效。
  2. 在下次更新无效记录期间,将评估约束并将失败 - 导致可能与实际更新无关的错误。
  3. 依赖约束来确保数据有效的应用程序逻辑可能会失败。
  4. 查询优化器不会使用以这种方式启用的任何约束。
  5. sys.foreign_keys系统视图提供了对该问题的一些可见性。请注意,它包含is_disabledis_not_trusted列。 is_disabled表示是否将根据约束验证未来的数据操作操作。 is_not_trusted表示当前表中的所有数据是否都已根据约束进行验证。

    ALTER TABLE MyTable WITH CHECK CHECK CONSTRAINT MyConstraint;
    

    您的约束是否值得信任?找出......

    SELECT * FROM sys.foreign_keys WHERE is_not_trusted = 1;
    

答案 9 :(得分:5)

找到约束

SELECT * 
FROM sys.foreign_keys
WHERE referenced_object_id = object_id('TABLE_NAME')

执行此SQL生成的SQL

SELECT 
    'ALTER TABLE ' +  OBJECT_SCHEMA_NAME(parent_object_id) +
    '.[' + OBJECT_NAME(parent_object_id) + 
    '] DROP CONSTRAINT ' + name
FROM sys.foreign_keys
WHERE referenced_object_id = object_id('TABLE_NAME')

西夫韦。

注意:添加了删除约束的解决方案,以便可以删除或修改表而不会出现任何约束错误。

答案 10 :(得分:1)

右键单击表设计并转到“关系”并在左侧窗格和右侧窗格中选择外键,将“强制外键约束”设置为“是”(以启用外键约束)或“否” '(禁用它)。 enter image description here

答案 11 :(得分:1)

标记为“905”的答案看起来不错但不起作用。

以下为我工作。任何主键,唯一键或默认约束 CAN NOT 都将被禁用。事实上,如果'sp_helpconstraint''在status_enabled中显示'n / a' - 意味着它可以 NOT 启用/禁用。

- 生成DISABLE的脚本

select 'ALTER TABLE ' + object_name(id) + ' NOCHECK CONSTRAINT [' + object_name(constid) + ']'
from sys.sysconstraints 
where status & 0x4813 = 0x813 order by object_name(id)

- 生成脚本以启用

select 'ALTER TABLE ' + object_name(id) + ' CHECK CONSTRAINT [' + object_name(constid) + ']'
from sys.sysconstraints 
where status & 0x4813 = 0x813 order by object_name(id)

答案 12 :(得分:1)

您实际上应该能够像暂时禁用其他约束一样禁用外键约束:

import pandas as pd

values = pd.DataFrame({0:[96,54,27,28],
          1:[55,75,32,37],2:[54,99,36,46],3:[35,77,0,10],4:[62,25,0,25],
          5:[0,66,0,89],6:[0,66,0,89],7:[0,0,0,0],8:[0,0,0,0]})

values[values.columns[::-1]].cumsum(axis=1).reindex_axis(values.columns, axis=1)

# returns:
     0    1    2    3    4    5   6  7  8
0  302  206  151   97   62    0   0  0  0
1  462  408  333  234  157  132  66  0  0
2   95   68   36    0    0    0   0  0  0
3  324  296  259  213  203  178  89  0  0

只需确保禁用约束名称中列出的第一个表上的约束。例如,如果我的外键约束是FK_LocationsEmployeesLocationIdEmployeeId,我想使用以下内容:

Alter table MyTable nocheck constraint FK_ForeignKeyConstraintName

即使违反此约束也会产生错误,该错误不一定表明该表是冲突的来源。

答案 13 :(得分:0)

如果您有兴趣,我有一个更有用的版本。我从这里提取了一些代码链接不再有效的代码。我修改它以允许存储过程中的表数组,并在执行所有表之前填充drop,truncate,add语句。这使您可以控制决定哪些表需要截断。

/****** Object:  UserDefinedTableType [util].[typ_objects_for_managing]    Script Date: 03/04/2016 16:42:55 ******/
CREATE TYPE [util].[typ_objects_for_managing] AS TABLE(
    [schema] [sysname] NOT NULL,
    [object] [sysname] NOT NULL
)
GO

create procedure [util].[truncate_table_with_constraints]
@objects_for_managing util.typ_objects_for_managing readonly

--@schema sysname
--,@table sysname

as 
--select
--    @table = 'TABLE',
--    @schema = 'SCHEMA'

declare @exec_table as table (ordinal int identity (1,1), statement nvarchar(4000), primary key (ordinal));

--print '/*Drop Foreign Key Statements for ['+@schema+'].['+@table+']*/'

insert into @exec_table (statement)
select
          'ALTER TABLE ['+SCHEMA_NAME(o.schema_id)+'].['+ o.name+'] DROP CONSTRAINT ['+fk.name+']'
from sys.foreign_keys fk
inner join sys.objects o
          on fk.parent_object_id = o.object_id
where 
exists ( 
select * from @objects_for_managing chk 
where 
chk.[schema] = SCHEMA_NAME(o.schema_id)  
and 
chk.[object] = o.name
) 
;
          --o.name = @table and
          --SCHEMA_NAME(o.schema_id)  = @schema

insert into @exec_table (statement) 
select
'TRUNCATE TABLE ' + src.[schema] + '.' + src.[object] 
from @objects_for_managing src
; 

--print '/*Create Foreign Key Statements for ['+@schema+'].['+@table+']*/'
insert into @exec_table (statement)
select 'ALTER TABLE ['+SCHEMA_NAME(o.schema_id)+'].['+o.name+'] ADD CONSTRAINT ['+fk.name+'] FOREIGN KEY (['+c.name+']) 
REFERENCES ['+SCHEMA_NAME(refob.schema_id)+'].['+refob.name+'](['+refcol.name+'])'
from sys.foreign_key_columns fkc
inner join sys.foreign_keys fk
          on fkc.constraint_object_id = fk.object_id
inner join sys.objects o
          on fk.parent_object_id = o.object_id
inner join sys.columns c
          on      fkc.parent_column_id = c.column_id and
                   o.object_id = c.object_id
inner join sys.objects refob
          on fkc.referenced_object_id = refob.object_id
inner join sys.columns refcol
          on fkc.referenced_column_id = refcol.column_id and
                   fkc.referenced_object_id = refcol.object_id
where 
exists ( 
select * from @objects_for_managing chk 
where 
chk.[schema] = SCHEMA_NAME(o.schema_id)  
and 
chk.[object] = o.name
) 
;

          --o.name = @table and
          --SCHEMA_NAME(o.schema_id)  = @schema



declare @looper int , @total_records int, @sql_exec nvarchar(4000)

select @looper = 1, @total_records = count(*) from @exec_table; 

while @looper <= @total_records 
begin

select @sql_exec = (select statement from @exec_table where ordinal =@looper)
exec sp_executesql @sql_exec 
print @sql_exec 
set @looper = @looper + 1
end

答案 14 :(得分:0)

一个脚本来统治它们:这将truncate和delete命令与sp_MSforeachtable相结合,这样你就可以避免删除和重新创建约束 - 只需指定需要删除而不是截断的表,为了我的目的,我已经包含了一个额外的模式过滤器以获得良好的测量结果(在2008r2中测试)

declare @schema nvarchar(max) = 'and Schema_Id=Schema_id(''Value'')'
declare @deletiontables nvarchar(max) = '(''TableA'',''TableB'')'
declare @truncateclause nvarchar(max) = @schema + ' and o.Name not in ' +  + @deletiontables;
declare @deleteclause nvarchar(max) = @schema + ' and o.Name in ' + @deletiontables;        

exec sp_MSforeachtable 'alter table ? nocheck constraint all', @whereand=@schema
exec sp_MSforeachtable 'truncate table ?', @whereand=@truncateclause
exec sp_MSforeachtable 'delete from ?', @whereand=@deleteclause
exec sp_MSforeachtable 'alter table ? with check check constraint all', @whereand=@schema

答案 15 :(得分:0)

您可以暂时禁用表上的约束,进行工作,然后重新构建它们。

这是一种简单的方法...

禁用所有索引,包括主键,这将禁用所有外键,然后仅重新启用主键,以便您可以使用它们...

DECLARE @sql AS NVARCHAR(max)=''
select @sql = @sql +
    'ALTER INDEX ALL ON [' + t.[name] + '] DISABLE;'+CHAR(13)
from  
    sys.tables t
where type='u'

select @sql = @sql +
    'ALTER INDEX ' + i.[name] + ' ON [' + t.[name] + '] REBUILD;'+CHAR(13)
from  
    sys.key_constraints i
join
    sys.tables t on i.parent_object_id=t.object_id
where
    i.type='PK'


exec dbo.sp_executesql @sql;
go

[执行某些操作,例如加载数据]

然后重新启用并重建索引...

DECLARE @sql AS NVARCHAR(max)=''
select @sql = @sql +
    'ALTER INDEX ALL ON [' + t.[name] + '] REBUILD;'+CHAR(13)
from  
    sys.tables t
where type='u'

exec dbo.sp_executesql @sql;
go