不能截断表，因为它正在被FOREIGN KEY约束引用。

使用MSSQL2005，如果我首先截断子表（具有FK关系主键的表），我可以截断具有外键约束的表吗？

我知道我也可以

使用没有where子句的DELETE ，然后RESEED身份（或）
删除FK，截断表，并重新创buildFK。

我认为，只要我截断父表之前的子表，我会没事没有做任何上述选项，但我得到这个错误：

无法截断表'TableName'，因为它正被FOREIGN KEY约束引用。

正确; 你不能截断一个有FK约束的表。

通常我的过程是这样的：

放下限制
截断表格
重新创build约束。

（当然，全部在交易中）

当然，这只适用于孩子已被截断的情况。 否则，我走一条不同的路线，完全依赖于我的数据看起来像什么。（太多的variables进入这里。）

原来的海报确定了为什么是这样的情况; 看到这个答案更多的细节。

 DELETE FROM TABLENAME DBCC CHECKIDENT ('DATABASENAME.dbo.TABLENAME',RESEED, 0)

由于TRUNCATE TABLE是DDL命令，因此无法检查表中的logging是否正在被子表中的logging引用。

这就是为什么DELETE工作和TRUNCATE TABLE不能：因为数据库能够确保它没有被另一个logging引用。

没有ALTER TABLE

 -- Delete all records DELETE FROM [TableName] -- Set current ID to "1" -- If table already contains data, use "0" -- If table is empty and never insert data, use "1" -- Use SP https://github.com/reduardo7/TableTruncate DBCC CHECKIDENT ([TableName], RESEED, [0|1])

作为存储过程

https://github.com/reduardo7/TableTruncate

上面提供的解决scheme@denver_citizen并不适用于我，但我喜欢它的精神，所以我修改了一些东西：

使它成为一个存储过程
改变了外键填充和重新创build的方式
原始脚本截断所有引用的表，这可能会导致外键违规错误引用表具有其他外键引用。该脚本仅截断指定为参数的表。由用户决定，以正确的顺序在所有表上多次调用该存储过程

为了公众的利益，这里是更新的脚本：

 CREATE PROCEDURE [dbo].[truncate_non_empty_table] @TableToTruncate VARCHAR(64) AS BEGIN SET NOCOUNT ON -- GLOBAL VARIABLES DECLARE @i int DECLARE @Debug bit DECLARE @Recycle bit DECLARE @Verbose bit DECLARE @TableName varchar(80) DECLARE @ColumnName varchar(80) DECLARE @ReferencedTableName varchar(80) DECLARE @ReferencedColumnName varchar(80) DECLARE @ConstraintName varchar(250) DECLARE @CreateStatement varchar(max) DECLARE @DropStatement varchar(max) DECLARE @TruncateStatement varchar(max) DECLARE @CreateStatementTemp varchar(max) DECLARE @DropStatementTemp varchar(max) DECLARE @TruncateStatementTemp varchar(max) DECLARE @Statement varchar(max) -- 1 = Will not execute statements SET @Debug = 0 -- 0 = Will not create or truncate storage table -- 1 = Will create or truncate storage table SET @Recycle = 0 -- 1 = Will print a message on every step set @Verbose = 1 SET @i = 1 SET @CreateStatement = 'ALTER TABLE [dbo].[<tablename>] WITH NOCHECK ADD CONSTRAINT [<constraintname>] FOREIGN KEY([<column>]) REFERENCES [dbo].[<reftable>] ([<refcolumn>])' SET @DropStatement = 'ALTER TABLE [dbo].[<tablename>] DROP CONSTRAINT [<constraintname>]' SET @TruncateStatement = 'TRUNCATE TABLE [<tablename>]' -- Drop Temporary tables IF OBJECT_ID('tempdb..#FKs') IS NOT NULL DROP TABLE #FKs -- GET FKs SELECT ROW_NUMBER() OVER (ORDER BY OBJECT_NAME(parent_object_id), clm1.name) as ID, OBJECT_NAME(constraint_object_id) as ConstraintName, OBJECT_NAME(parent_object_id) as TableName, clm1.name as ColumnName, OBJECT_NAME(referenced_object_id) as ReferencedTableName, clm2.name as ReferencedColumnName INTO #FKs FROM sys.foreign_key_columns fk JOIN sys.columns clm1 ON fk.parent_column_id = clm1.column_id AND fk.parent_object_id = clm1.object_id JOIN sys.columns clm2 ON fk.referenced_column_id = clm2.column_id AND fk.referenced_object_id= clm2.object_id --WHERE OBJECT_NAME(parent_object_id) not in ('//tables that you do not wont to be truncated') WHERE OBJECT_NAME(referenced_object_id) = @TableToTruncate ORDER BY OBJECT_NAME(parent_object_id) -- Prepare Storage Table IF Not EXISTS(SELECT 1 FROM INFORMATION_SCHEMA.TABLES WHERE TABLE_NAME = 'Internal_FK_Definition_Storage') BEGIN IF @Verbose = 1 PRINT '1. Creating Process Specific Tables...' -- CREATE STORAGE TABLE IF IT DOES NOT EXISTS CREATE TABLE [Internal_FK_Definition_Storage] ( ID int not null identity(1,1) primary key, FK_Name varchar(250) not null, FK_CreationStatement varchar(max) not null, FK_DestructionStatement varchar(max) not null, Table_TruncationStatement varchar(max) not null ) END ELSE BEGIN IF @Recycle = 0 BEGIN IF @Verbose = 1 PRINT '1. Truncating Process Specific Tables...' -- TRUNCATE TABLE IF IT ALREADY EXISTS TRUNCATE TABLE [Internal_FK_Definition_Storage] END ELSE PRINT '1. Process specific table will be recycled from previous execution...' END IF @Recycle = 0 BEGIN IF @Verbose = 1 PRINT '2. Backing up Foreign Key Definitions...' -- Fetch and persist FKs WHILE (@i <= (SELECT MAX(ID) FROM #FKs)) BEGIN SET @ConstraintName = (SELECT ConstraintName FROM #FKs WHERE ID = @i) SET @TableName = (SELECT TableName FROM #FKs WHERE ID = @i) SET @ColumnName = (SELECT ColumnName FROM #FKs WHERE ID = @i) SET @ReferencedTableName = (SELECT ReferencedTableName FROM #FKs WHERE ID = @i) SET @ReferencedColumnName = (SELECT ReferencedColumnName FROM #FKs WHERE ID = @i) SET @DropStatementTemp = REPLACE(REPLACE(@DropStatement,'<tablename>',@TableName),'<constraintname>',@ConstraintName) SET @CreateStatementTemp = REPLACE(REPLACE(REPLACE(REPLACE(REPLACE(@CreateStatement,'<tablename>',@TableName),'<column>',@ColumnName),'<constraintname>',@ConstraintName),'<reftable>',@ReferencedTableName),'<refcolumn>',@ReferencedColumnName) SET @TruncateStatementTemp = REPLACE(@TruncateStatement,'<tablename>',@TableName) INSERT INTO [Internal_FK_Definition_Storage] SELECT @ConstraintName, @CreateStatementTemp, @DropStatementTemp, @TruncateStatementTemp SET @i = @i + 1 IF @Verbose = 1 PRINT ' > Backing up [' + @ConstraintName + '] from [' + @TableName + ']' END END ELSE PRINT '2. Backup up was recycled from previous execution...' IF @Verbose = 1 PRINT '3. Dropping Foreign Keys...' -- DROP FOREING KEYS SET @i = 1 WHILE (@i <= (SELECT MAX(ID) FROM [Internal_FK_Definition_Storage])) BEGIN SET @ConstraintName = (SELECT FK_Name FROM [Internal_FK_Definition_Storage] WHERE ID = @i) SET @Statement = (SELECT FK_DestructionStatement FROM [Internal_FK_Definition_Storage] WITH (NOLOCK) WHERE ID = @i) IF @Debug = 1 PRINT @Statement ELSE EXEC(@Statement) SET @i = @i + 1 IF @Verbose = 1 PRINT ' > Dropping [' + @ConstraintName + ']' END IF @Verbose = 1 PRINT '4. Truncating Tables...' -- TRUNCATE TABLES -- SzP: commented out as the tables to be truncated might also contain tables that has foreign keys -- to resolve this the stored procedure should be called recursively, but I dont have the time to do it... /* SET @i = 1 WHILE (@i <= (SELECT MAX(ID) FROM [Internal_FK_Definition_Storage])) BEGIN SET @Statement = (SELECT Table_TruncationStatement FROM [Internal_FK_Definition_Storage] WHERE ID = @i) IF @Debug = 1 PRINT @Statement ELSE EXEC(@Statement) SET @i = @i + 1 IF @Verbose = 1 PRINT ' > ' + @Statement END */ IF @Verbose = 1 PRINT ' > TRUNCATE TABLE [' + @TableToTruncate + ']' IF @Debug = 1 PRINT 'TRUNCATE TABLE [' + @TableToTruncate + ']' ELSE EXEC('TRUNCATE TABLE [' + @TableToTruncate + ']') IF @Verbose = 1 PRINT '5. Re-creating Foreign Keys...' -- CREATE FOREING KEYS SET @i = 1 WHILE (@i <= (SELECT MAX(ID) FROM [Internal_FK_Definition_Storage])) BEGIN SET @ConstraintName = (SELECT FK_Name FROM [Internal_FK_Definition_Storage] WHERE ID = @i) SET @Statement = (SELECT FK_CreationStatement FROM [Internal_FK_Definition_Storage] WHERE ID = @i) IF @Debug = 1 PRINT @Statement ELSE EXEC(@Statement) SET @i = @i + 1 IF @Verbose = 1 PRINT ' > Re-creating [' + @ConstraintName + ']' END IF @Verbose = 1 PRINT '6. Process Completed' END

使用delete语句删除该表中的所有行后，使用以下命令

 delete from tablename DBCC CHECKIDENT ('tablename', RESEED, 0)

编辑：更正SQL Server的语法

你可以按照这个步骤，通过reseeding table你可以删除reseeding table的数据。

 delete from table_name dbcc checkident('table_name',reseed,0)

如果出现一些错误，则必须重新设置主表。

这是我为了使这个过程自动化而写的一个脚本。我希望它有帮助。

 SET NOCOUNT ON -- GLOBAL VARIABLES DECLARE @i int DECLARE @Debug bit DECLARE @Recycle bit DECLARE @Verbose bit DECLARE @TableName varchar(80) DECLARE @ColumnName varchar(80) DECLARE @ReferencedTableName varchar(80) DECLARE @ReferencedColumnName varchar(80) DECLARE @ConstraintName varchar(250) DECLARE @CreateStatement varchar(max) DECLARE @DropStatement varchar(max) DECLARE @TruncateStatement varchar(max) DECLARE @CreateStatementTemp varchar(max) DECLARE @DropStatementTemp varchar(max) DECLARE @TruncateStatementTemp varchar(max) DECLARE @Statement varchar(max) -- 1 = Will not execute statements SET @Debug = 0 -- 0 = Will not create or truncate storage table -- 1 = Will create or truncate storage table SET @Recycle = 0 -- 1 = Will print a message on every step set @Verbose = 1 SET @i = 1 SET @CreateStatement = 'ALTER TABLE [dbo].[<tablename>] WITH NOCHECK ADD CONSTRAINT [<constraintname>] FOREIGN KEY([<column>]) REFERENCES [dbo].[<reftable>] ([<refcolumn>])' SET @DropStatement = 'ALTER TABLE [dbo].[<tablename>] DROP CONSTRAINT [<constraintname>]' SET @TruncateStatement = 'TRUNCATE TABLE [<tablename>]' -- Drop Temporary tables DROP TABLE #FKs -- GET FKs SELECT ROW_NUMBER() OVER (ORDER BY OBJECT_NAME(parent_object_id), clm1.name) as ID, OBJECT_NAME(constraint_object_id) as ConstraintName, OBJECT_NAME(parent_object_id) as TableName, clm1.name as ColumnName, OBJECT_NAME(referenced_object_id) as ReferencedTableName, clm2.name as ReferencedColumnName INTO #FKs FROM sys.foreign_key_columns fk JOIN sys.columns clm1 ON fk.parent_column_id = clm1.column_id AND fk.parent_object_id = clm1.object_id JOIN sys.columns clm2 ON fk.referenced_column_id = clm2.column_id AND fk.referenced_object_id= clm2.object_id WHERE OBJECT_NAME(parent_object_id) not in ('//tables that you do not wont to be truncated') ORDER BY OBJECT_NAME(parent_object_id) -- Prepare Storage Table IF Not EXISTS(SELECT 1 FROM INFORMATION_SCHEMA.TABLES WHERE TABLE_NAME = 'Internal_FK_Definition_Storage') BEGIN IF @Verbose = 1 PRINT '1. Creating Process Specific Tables...' -- CREATE STORAGE TABLE IF IT DOES NOT EXISTS CREATE TABLE [Internal_FK_Definition_Storage] ( ID int not null identity(1,1) primary key, FK_Name varchar(250) not null, FK_CreationStatement varchar(max) not null, FK_DestructionStatement varchar(max) not null, Table_TruncationStatement varchar(max) not null ) END ELSE BEGIN IF @Recycle = 0 BEGIN IF @Verbose = 1 PRINT '1. Truncating Process Specific Tables...' -- TRUNCATE TABLE IF IT ALREADY EXISTS TRUNCATE TABLE [Internal_FK_Definition_Storage] END ELSE PRINT '1. Process specific table will be recycled from previous execution...' END IF @Recycle = 0 BEGIN IF @Verbose = 1 PRINT '2. Backing up Foreign Key Definitions...' -- Fetch and persist FKs WHILE (@i <= (SELECT MAX(ID) FROM #FKs)) BEGIN SET @ConstraintName = (SELECT ConstraintName FROM #FKs WHERE ID = @i) SET @TableName = (SELECT TableName FROM #FKs WHERE ID = @i) SET @ColumnName = (SELECT ColumnName FROM #FKs WHERE ID = @i) SET @ReferencedTableName = (SELECT ReferencedTableName FROM #FKs WHERE ID = @i) SET @ReferencedColumnName = (SELECT ReferencedColumnName FROM #FKs WHERE ID = @i) SET @DropStatementTemp = REPLACE(REPLACE(@DropStatement,'<tablename>',@TableName),'<constraintname>',@ConstraintName) SET @CreateStatementTemp = REPLACE(REPLACE(REPLACE(REPLACE(REPLACE(@CreateStatement,'<tablename>',@TableName),'<column>',@ColumnName),'<constraintname>',@ConstraintName),'<reftable>',@ReferencedTableName),'<refcolumn>',@ReferencedColumnName) SET @TruncateStatementTemp = REPLACE(@TruncateStatement,'<tablename>',@TableName) INSERT INTO [Internal_FK_Definition_Storage] SELECT @ConstraintName, @CreateStatementTemp, @DropStatementTemp, @TruncateStatementTemp SET @i = @i + 1 IF @Verbose = 1 PRINT ' > Backing up [' + @ConstraintName + '] from [' + @TableName + ']' END END ELSE PRINT '2. Backup up was recycled from previous execution...' IF @Verbose = 1 PRINT '3. Dropping Foreign Keys...' -- DROP FOREING KEYS SET @i = 1 WHILE (@i <= (SELECT MAX(ID) FROM [Internal_FK_Definition_Storage])) BEGIN SET @ConstraintName = (SELECT FK_Name FROM [Internal_FK_Definition_Storage] WHERE ID = @i) SET @Statement = (SELECT FK_DestructionStatement FROM [Internal_FK_Definition_Storage] WITH (NOLOCK) WHERE ID = @i) IF @Debug = 1 PRINT @Statement ELSE EXEC(@Statement) SET @i = @i + 1 IF @Verbose = 1 PRINT ' > Dropping [' + @ConstraintName + ']' END IF @Verbose = 1 PRINT '4. Truncating Tables...' -- TRUNCATE TABLES SET @i = 1 WHILE (@i <= (SELECT MAX(ID) FROM [Internal_FK_Definition_Storage])) BEGIN SET @Statement = (SELECT Table_TruncationStatement FROM [Internal_FK_Definition_Storage] WHERE ID = @i) IF @Debug = 1 PRINT @Statement ELSE EXEC(@Statement) SET @i = @i + 1 IF @Verbose = 1 PRINT ' > ' + @Statement END IF @Verbose = 1 PRINT '5. Re-creating Foreign Keys...' -- CREATE FOREING KEYS SET @i = 1 WHILE (@i <= (SELECT MAX(ID) FROM [Internal_FK_Definition_Storage])) BEGIN SET @ConstraintName = (SELECT FK_Name FROM [Internal_FK_Definition_Storage] WHERE ID = @i) SET @Statement = (SELECT FK_CreationStatement FROM [Internal_FK_Definition_Storage] WHERE ID = @i) IF @Debug = 1 PRINT @Statement ELSE EXEC(@Statement) SET @i = @i + 1 IF @Verbose = 1 PRINT ' > Re-creating [' + @ConstraintName + ']' END IF @Verbose = 1 PRINT '6. Process Completed'

在networking上的其他地方find

 EXEC sp_MSForEachTable 'ALTER TABLE ? NOCHECK CONSTRAINT ALL' EXEC sp_MSForEachTable 'ALTER TABLE ? DISABLE TRIGGER ALL' -- EXEC sp_MSForEachTable 'DELETE FROM ?' -- Uncomment to execute EXEC sp_MSForEachTable 'ALTER TABLE ? CHECK CONSTRAINT ALL' EXEC sp_MSForEachTable 'ALTER TABLE ? ENABLE TRIGGER ALL'

那么，因为我没有find我使用的非常简单的解决scheme的例子，这是：

放弃外键;
截断表
重新创build外键

这里是：

1）find引起失败的外键名称（例如：FK_PROBLEM_REASON，字段ID ，来自表TABLE_OWNING_CONSTRAINT ）2）从表中删除该键：

 ALTER TABLE TABLE_OWNING_CONSTRAINT DROP CONSTRAINT FK_PROBLEM_REASON

3）截断想要的表格

 TRUNCATE TABLE TABLE_TO_TRUNCATE

4）重新添加到第一个表的关键：

 ALTER TABLE TABLE_OWNING_CONSTRAINT ADD CONSTRAINT FK_PROBLEM_REASON FOREIGN KEY(ID) REFERENCES TABLE_TO_TRUNCATE (ID)

而已。

如果我理解正确，你想要做的是为涉及集成testing的数据库设置一个干净的环境。

我的方法是删除整个模式，然后重新创build。

原因：

您可能已经有一个“创build架构”脚本。重新使用它进行testing隔离是很容易的。
创build一个模式非常快。
通过这种方法，设置脚本使每个灯具创build一个新的模式（使用临时名称）非常简单，然后就可以开始同时运行testing灯具，使testing套件中速度最慢的部分快得多。

如果不删除约束，则不能截断表。禁用也不起作用。你需要放下一切。我做了一个脚本，放下所有的约束，然后重新创build。

一定要把它包装在一个交易中;）

 SET NOCOUNT ON GO 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 --DROP CONSTRAINT: DECLARE @dynSQL varchar(MAX); DECLARE cur CURSOR FOR SELECT ' ALTER TABLE [' + ForeignKeyConstraintTableSchema + '].[' + ForeignKeyConstraintTableName + '] DROP CONSTRAINT ' + ForeignKeyConstraintName + ' ' FROM @table OPEN cur FETCH cur into @dynSQL WHILE @@FETCH_STATUS = 0 BEGIN exec(@dynSQL) print @dynSQL FETCH cur into @dynSQL END CLOSE cur DEALLOCATE cur --------------------- --HERE GOES YOUR TRUNCATES!!!!! --HERE GOES YOUR TRUNCATES!!!!! --HERE GOES YOUR TRUNCATES!!!!! truncate table your_table --HERE GOES YOUR TRUNCATES!!!!! --HERE GOES YOUR TRUNCATES!!!!! --HERE GOES YOUR TRUNCATES!!!!! --------------------- --ADD CONSTRAINT: DECLARE cur2 CURSOR FOR SELECT ' ALTER TABLE [' + ForeignKeyConstraintTableSchema + '].[' + ForeignKeyConstraintTableName + '] ADD CONSTRAINT ' + ForeignKeyConstraintName + ' FOREIGN KEY(' + ForeignKeyConstraintColumnName + ') REFERENCES [' + PrimaryKeyConstraintTableSchema + '].[' + PrimaryKeyConstraintTableName + '](' + PrimaryKeyConstraintColumnName + ') ' FROM @table OPEN cur2 FETCH cur2 into @dynSQL WHILE @@FETCH_STATUS = 0 BEGIN exec(@dynSQL) print @dynSQL FETCH cur2 into @dynSQL END CLOSE cur2 DEALLOCATE cur2

截断没有为我工作，删除+种子是最好的出路。如果有些人需要遍历大量的表来执行delete + reseed，那么你可能遇到一些没有标识列的表的问题，下面的代码会在尝试之前检查标识列是否存在种子

  EXEC ('DELETE FROM [schemaName].[tableName]') IF EXISTS (Select * from sys.identity_columns where object_name(object_id) = 'tableName') BEGIN EXEC ('DBCC CHECKIDENT ([schemaName.tableName], RESEED, 0)') END

下面的工作对我来说甚至与FK的限制，并结合下面的答案只删除指定的表 ：

事务自动回滚
循环通过逗号分隔的列表
执行dynamicSQL（使用variables中的表名）
DELETE和RESEED表 （在这个线程中）

 USE [YourDB]; DECLARE @TransactionName varchar(20) = 'stopdropandroll'; BEGIN TRAN @TransactionName; set xact_abort on; /* automatic rollback https://stackoverflow.com/a/1749788/1037948 */ -- ===== DO WORK // ===== -- dynamic sql placeholder DECLARE @SQL varchar(300); -- LOOP: https://stackoverflow.com/a/10031803/1037948 -- list of things to loop DECLARE @delim char = ';'; DECLARE @foreach varchar(MAX) = 'Table;Names;Separated;By;Delimiter' + @delim + 'AnotherName' + @delim + 'Still Another'; DECLARE @token varchar(MAX); WHILE len(@foreach) > 0 BEGIN -- set current loop token SET @token = left(@foreach, charindex(@delim, @foreach+@delim)-1) -- ======= DO WORK // =========== -- dynamic sql (parentheses are required): https://stackoverflow.com/a/989111/1037948 SET @SQL = 'DELETE FROM [' + @token + ']; DBCC CHECKIDENT (''' + @token + ''',RESEED, 0);'; -- https://stackoverflow.com/a/11784890 PRINT @SQL; EXEC (@SQL); -- ======= // END WORK =========== -- continue loop, chopping off token SET @foreach = stuff(@foreach, 1, charindex(@delim, @foreach+@delim), '') END -- ===== // END WORK ===== -- review and commit SELECT @@TRANCOUNT as TransactionsPerformed, @@ROWCOUNT as LastRowsChanged; COMMIT TRAN @TransactionName;

注意：

我认为它仍然有助于按照您希望它们删除的顺序来声明表（即先杀死依赖关系）。正如在这个答案中看到的，而不是循环特定的名字，你可以用所有的表replace

 EXEC sp_MSForEachTable 'DELETE FROM ?; DBCC CHECKIDENT (''?'',RESEED, 0);';

这是我解决这个问题的方法。我用它来改变PK，但想法是一样的。希望这会有用）

 PRINT 'Script starts' DECLARE @foreign_key_name varchar(255) DECLARE @keycnt int DECLARE @foreign_table varchar(255) DECLARE @foreign_column_1 varchar(255) DECLARE @foreign_column_2 varchar(255) DECLARE @primary_table varchar(255) DECLARE @primary_column_1 varchar(255) DECLARE @primary_column_2 varchar(255) DECLARE @TablN varchar(255) -->> Type the primary table name SET @TablN = '' --------------------------------------------------------------------------------------- ------------------------------ --Here will be created the temporary table with all reference FKs --------------------------------------------------------------------------------------------------------------------- PRINT 'Creating the temporary table' select cast(f.name as varchar(255)) as foreign_key_name , r.keycnt , cast(c.name as varchar(255)) as foreign_table , cast(fc.name as varchar(255)) as foreign_column_1 , cast(fc2.name as varchar(255)) as foreign_column_2 , cast(p.name as varchar(255)) as primary_table , cast(rc.name as varchar(255)) as primary_column_1 , cast(rc2.name as varchar(255)) as primary_column_2 into #ConTab from sysobjects f inner join sysobjects c on f.parent_obj = c.id inner join sysreferences r on f.id = r.constid inner join sysobjects p on r.rkeyid = p.id inner join syscolumns rc on r.rkeyid = rc.id and r.rkey1 = rc.colid inner join syscolumns fc on r.fkeyid = fc.id and r.fkey1 = fc.colid left join syscolumns rc2 on r.rkeyid = rc2.id and r.rkey2 = rc.colid left join syscolumns fc2 on r.fkeyid = fc2.id and r.fkey2 = fc.colid where f.type = 'F' and p.name = @TablN ORDER BY cast(p.name as varchar(255)) --------------------------------------------------------------------------------------------------------------------- --Cursor, below, will drop all reference FKs --------------------------------------------------------------------------------------------------------------------- DECLARE @CURSOR CURSOR /*Fill in cursor*/ PRINT 'Cursor 1 starting. All refernce FK will be droped' SET @CURSOR = CURSOR SCROLL FOR select foreign_key_name , keycnt , foreign_table , foreign_column_1 , foreign_column_2 , primary_table , primary_column_1 , primary_column_2 from #ConTab OPEN @CURSOR FETCH NEXT FROM @CURSOR INTO @foreign_key_name, @keycnt, @foreign_table, @foreign_column_1, @foreign_column_2, @primary_table, @primary_column_1, @primary_column_2 WHILE @@FETCH_STATUS = 0 BEGIN EXEC ('ALTER TABLE ['+@foreign_table+'] DROP CONSTRAINT ['+@foreign_key_name+']') FETCH NEXT FROM @CURSOR INTO @foreign_key_name, @keycnt, @foreign_table, @foreign_column_1, @foreign_column_2, @primary_table, @primary_column_1, @primary_column_2 END CLOSE @CURSOR PRINT 'Cursor 1 finished work' --------------------------------------------------------------------------------------------------------------------- --Here you should provide the chainging script for the primary table --------------------------------------------------------------------------------------------------------------------- PRINT 'Altering primary table begin' TRUNCATE TABLE table_name PRINT 'Altering finished' --------------------------------------------------------------------------------------------------------------------- --Cursor, below, will add again all reference FKs -------------------------------------------------------------------------------------------------------------------- PRINT 'Cursor 2 starting. All refernce FK will added' SET @CURSOR = CURSOR SCROLL FOR select foreign_key_name , keycnt , foreign_table , foreign_column_1 , foreign_column_2 , primary_table , primary_column_1 , primary_column_2 from #ConTab OPEN @CURSOR FETCH NEXT FROM @CURSOR INTO @foreign_key_name, @keycnt, @foreign_table, @foreign_column_1, @foreign_column_2, @primary_table, @primary_column_1, @primary_column_2 WHILE @@FETCH_STATUS = 0 BEGIN EXEC ('ALTER TABLE [' +@foreign_table+ '] WITH NOCHECK ADD CONSTRAINT [' +@foreign_key_name+ '] FOREIGN KEY(['+@foreign_column_1+']) REFERENCES [' +@primary_table+'] (['+@primary_column_1+'])') EXEC ('ALTER TABLE [' +@foreign_table+ '] CHECK CONSTRAINT [' +@foreign_key_name+']') FETCH NEXT FROM @CURSOR INTO @foreign_key_name, @keycnt, @foreign_table, @foreign_column_1, @foreign_column_2, @primary_table, @primary_column_1, @primary_column_2 END CLOSE @CURSOR PRINT 'Cursor 2 finished work' --------------------------------------------------------------------------------------------------------------------- PRINT 'Temporary table droping' drop table #ConTab PRINT 'Finish'

If none of these answers worked like in my case do this:

Drop constraints
Set all values to allow nulls
Truncate table
Add constraints that were dropped.

祝你好运！

SET FOREIGN_KEY_CHECKS=0;

truncate table "tableName";

SET FOREIGN_KEY_CHECKS=1;

For MS SQL , at least the newer versions, you can just disable the constrains with code like this:

 ALTER TABLE Orders NOCHECK CONSTRAINT [FK_dbo.Orders_dbo.Customers_Customer_Id] GO TRUNCATE TABLE Customers GO ALTER TABLE Orders WITH CHECK CHECK CONSTRAINT [FK_dbo.Orders_dbo.Customers_Customer_Id] GO

In SSMS I had Diagram open showing the Key. After deleting the Key and truncating the file I refreshed then focused back on the Diagram and created an update by clearing then restoring an Identity box. Saving the Diagram brought up a Save dialog box, than a "Changes were made in the database while you where working" dialog box, clicking Yes restored the Key, restoring it from the latched copy in the Diagram.

If you're doing this at any sort of a frequency, heck even on a schedule, I would absolutely, unequivocally never use a DML statement. The cost of writing to the transaction log is just to high, and setting the entire database into SIMPLE recovery mode to truncate one table is ridiculous.

The best way, is unfortunately the hard or laborious way. That being:

Drop constraints
Truncate table
Re-create constraints

My process for doing this involves the following steps:

In SSMS right-click on the table in question, and select View Dependencies
Take note of the tables referenced (if any)
Back in object explorer, expand the Keys node and take note of the foreign keys (if any)
Start scripting (drop / truncate / re-create)

Scripts of this nature should be done within a begin tran and commit tran block.

I write the following ways and tried to parameterized them, so you can Run them in a Query document Or Make a useful SP with them easily .

A) Delete

If your table has not millions of records this works good and hasn't any Alter commands :

 --------------------------------------------------------------- ------------------- Just Fill Parameters Value ---------------- --------------------------------------------------------------- DECLARE @DbName AS NVARCHAR(30) = 'MyDb' --< Db Name DECLARE @Schema AS NVARCHAR(30) = 'dbo' --< Schema DECLARE @TableName AS NVARCHAR(30) = 'Book' --< Table Name ------------------ /Just Fill Parameters Value ---------------- DECLARE @Query AS NVARCHAR(500) = 'Delete FROM ' + @TableName EXECUTE sp_executesql @Query SET @Query=@DbName+'.'+@Schema+'.'+@TableName DBCC CHECKIDENT (@Query,RESEED, 0)

In above answer of mine the method of resolve the mentioned problem in the question is based on @s15199d answer .

B) Truncate

If your table has millions of records or you hasn't any problem with Alter command in your codes, then use this one:

 -- Book Student -- -- | BookId | Field1 | | StudentId | BookId | -- --------------------- ------------------------ -- | 1 | A | | 2 | 1 | -- | 2 | B | | 1 | 1 | -- | 3 | C | | 2 | 3 | --------------------------------------------------------------- ------------------- Just Fill Parameters Value ---------------- --------------------------------------------------------------- DECLARE @DbName AS NVARCHAR(30) = 'MyDb' DECLARE @Schema AS NVARCHAR(30) = 'dbo' DECLARE @TableName_ToTruncate AS NVARCHAR(30) = 'Book' DECLARE @TableName_OfOwnerOfConstraint AS NVARCHAR(30) = 'Student' --< Decelations About FK_Book_Constraint DECLARE @Ref_ColumnName_In_TableName_ToTruncate AS NVARCHAR(30) = 'BookId' --< Decelations About FK_Book_Constraint DECLARE @FK_ColumnName_In_TableOfOwnerOfConstraint AS NVARCHAR(30) = 'Fk_BookId' --< Decelations About FK_Book_Constraint DECLARE @FK_ConstraintName AS NVARCHAR(30) = 'FK_Book_Constraint' --< Decelations About FK_Book_Constraint ------------------ /Just Fill Parameters Value ---------------- DECLARE @Query AS NVARCHAR(2000) SET @Query= 'ALTER TABLE '+@TableName_OfOwnerOfConstraint+' DROP CONSTRAINT '+@FK_ConstraintName EXECUTE sp_executesql @Query SET @Query= 'Truncate Table '+ @TableName_ToTruncate EXECUTE sp_executesql @Query SET @Query= 'ALTER TABLE '+@TableName_OfOwnerOfConstraint+' ADD CONSTRAINT '+@FK_ConstraintName+' FOREIGN KEY('+@FK_ColumnName_In_TableOfOwnerOfConstraint+') REFERENCES '+@TableName_ToTruncate+'('+@Ref_ColumnName_In_TableName_ToTruncate+')' EXECUTE sp_executesql @Query

In above answer of mine the method of resolve the mentioned problem in the question is based on @LauroWolffValenteSobrinho answer .

If you have more than one CONSTRAINT then you should append its codes like me to the above query

Also you can change the above code base @SerjSagan answer to disable an enable the constraint

You could try DELETE FROM <your table >; 。

The server will show you the name of the restriction and the table, and deleting that table you can delete what you need.

I have just found that you can use TRUNCATE table on a parent table with foreign key constraints on a child as long as you DISABLE the constraints on the child table first. 例如

Foreign key CONSTRAINT child_par_ref on child table, references PARENT_TABLE

 ALTER TABLE CHILD_TABLE DISABLE CONSTRAINT child_par_ref; TRUNCATE TABLE CHILD_TABLE; TRUNCATE TABLE PARENT_TABLE; ALTER TABLE CHILD_TABLE ENABLE CONSTRAINT child_par_ref;

最简单的方法是：
1 – Enter in phpmyadmin
2 – Click on table name in left column
3 – Click in Operation (top menu)
4 – Click "Empty the table (TRUNCATE)
5 – Disable box "Enable foreign key checks"
6 – Done!

Link to image tutorial
Tutorial: http://www.imageno.com/wz6gv1wuqajrpic.html
(sorry, I don't have enough reputation to upload images here :P)

 SET FOREIGN_KEY_CHECKS=0; TRUNCATE table1; TRUNCATE table2; SET FOREIGN_KEY_CHECKS=1;

reference – truncate foreign key constrained table

Working for me in MYSQL

不能截断表，因为它正在被FOREIGN KEY约束引用。

作为存储过程

原因：

A) Delete

B) Truncate

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