在使用delete语句删除表中的所有行之后，使用以下命令

delete from tablename

DBCC CHECKIDENT ('tablename', RESEED, 0)

编辑:修正的SQL Server语法

对于MS SQL，至少在更新的版本中，你可以通过如下代码禁用约束:

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

该过程是去除外键约束和截断表 然后按以下步骤添加约束。

这只是MySQL

SET FOREIGN_KEY_CHECKS = 0; 

truncate table "yourTableName";

SET FOREIGN_KEY_CHECKS = 1;

正确的;你不能截断一个有FK约束的表。

通常我的处理方法是:

去掉约束 截断表格 重新创建约束。

(当然，这一切都在一笔交易中。)

当然，这只适用于子节点已经被截断的情况。否则，我会走不同的路线，完全取决于我的数据是什么样子的。(变量太多，不便在此赘述。)

最初的海报决定了为什么会这样;更多细节请看这个答案。

好吧，因为我没有找到我使用的非常简单的解决方案的例子，这是:

删除外键; 截断表 重新创建外键

是这样的:

1)查找导致失败的外键名称(例如:FK_PROBLEM_REASON，带字段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)截断招聘表

TRUNCATE TABLE TABLE_TO_TRUNCATE

4)重新添加第一个表的键:

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

就是这样。

如果不删除约束，就不能截断表。disable也不行。你需要放下一切。我已经做了一个脚本，删除所有约束，然后重新创建。

请确保将其包装在事务中;)

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