我试图写一个脚本,将完全清空SQL Server数据库。这是我目前所拥有的:

USE [dbname]
GO
EXEC sp_msforeachtable 'ALTER TABLE ? NOCHECK CONSTRAINT all'
EXEC sp_msforeachtable 'DELETE ?'

当我在管理工作室运行它时,我得到:

命令执行成功。

但当我刷新表列表时,它们都还在那里。我做错了什么?


当前回答

当有多个外键表时,它也不适合我。 我发现,代码的工作,并做一切你尝试(删除所有表从你的数据库):

DECLARE @Sql NVARCHAR(500) DECLARE @Cursor CURSOR

SET @Cursor = CURSOR FAST_FORWARD FOR
SELECT DISTINCT sql = 'ALTER TABLE [' + tc2.TABLE_SCHEMA + '].[' +  tc2.TABLE_NAME + '] DROP [' + rc1.CONSTRAINT_NAME + '];'
FROM INFORMATION_SCHEMA.REFERENTIAL_CONSTRAINTS rc1
LEFT JOIN INFORMATION_SCHEMA.TABLE_CONSTRAINTS tc2 ON tc2.CONSTRAINT_NAME =rc1.CONSTRAINT_NAME

OPEN @Cursor FETCH NEXT FROM @Cursor INTO @Sql

WHILE (@@FETCH_STATUS = 0)
BEGIN
Exec sp_executesql @Sql
FETCH NEXT FROM @Cursor INTO @Sql
END

CLOSE @Cursor DEALLOCATE @Cursor
GO

EXEC sp_MSforeachtable 'DROP TABLE ?'
GO

你可以在这里找到帖子。这是格罗克的帖子。

其他回答

你差不多说对了,可以用:

EXEC sp_msforeachtable 'ALTER TABLE ? NOCHECK CONSTRAINT all'
EXEC sp_msforeachtable 'DROP TABLE ?'

但是第二行你可能需要执行不止一次,直到你停止得到错误:

Could not drop object 'dbo.table' because it is referenced by a FOREIGN KEY constraint.

信息:

Command(s) completed successfully.

表示已成功删除所有表。

/* Drop all Primary Key constraints */
DECLARE @name VARCHAR(128)
DECLARE @constraint VARCHAR(254)
DECLARE @SQL VARCHAR(254)

SELECT @name = (SELECT TOP 1 TABLE_NAME FROM INFORMATION_SCHEMA.TABLE_CONSTRAINTS WHERE constraint_catalog=DB_NAME() AND CONSTRAINT_TYPE = 'PRIMARY KEY' ORDER BY TABLE_NAME)

WHILE @name IS NOT NULL
BEGIN
    SELECT @constraint = (SELECT TOP 1 CONSTRAINT_NAME FROM INFORMATION_SCHEMA.TABLE_CONSTRAINTS WHERE constraint_catalog=DB_NAME() AND CONSTRAINT_TYPE = 'PRIMARY KEY' AND TABLE_NAME = @name ORDER BY CONSTRAINT_NAME)
    WHILE @constraint is not null
    BEGIN
        SELECT @SQL = 'ALTER TABLE [dbo].[' + RTRIM(@name) +'] DROP CONSTRAINT [' + RTRIM(@constraint)+']'
        EXEC (@SQL)
        PRINT 'Dropped PK Constraint: ' + @constraint + ' on ' + @name
        SELECT @constraint = (SELECT TOP 1 CONSTRAINT_NAME FROM INFORMATION_SCHEMA.TABLE_CONSTRAINTS WHERE constraint_catalog=DB_NAME() AND CONSTRAINT_TYPE = 'PRIMARY KEY' AND CONSTRAINT_NAME <> @constraint AND TABLE_NAME = @name ORDER BY CONSTRAINT_NAME)
    END
SELECT @name = (SELECT TOP 1 TABLE_NAME FROM INFORMATION_SCHEMA.TABLE_CONSTRAINTS WHERE constraint_catalog=DB_NAME() AND CONSTRAINT_TYPE = 'PRIMARY KEY' ORDER BY TABLE_NAME)
END
GO

/* Drop all tables */
DECLARE @name VARCHAR(128)
DECLARE @SQL VARCHAR(254)

SELECT @name = (SELECT TOP 1 [name] FROM sysobjects WHERE [type] = 'U' AND category = 0 ORDER BY [name])

WHILE @name IS NOT NULL
BEGIN
    SELECT @SQL = 'DROP TABLE [dbo].[' + RTRIM(@name) +']'
    EXEC (@SQL)
    PRINT 'Dropped Table: ' + @name
    SELECT @name = (SELECT TOP 1 [name] FROM sysobjects WHERE [type] = 'U' AND category = 0 AND [name] > @name ORDER BY [name])
END
GO

对于时态表来说,由于可能会有一些外键和例外,这有点复杂:

在表XXX上执行删除表操作失败,因为在系统版本的时态表上不支持该操作

你可以使用的是:

-- Disable constraints (foreign keys)
EXEC sp_MSForEachTable 'ALTER TABLE ? NOCHECK CONSTRAINT ALL'
GO

-- Disable system versioning (temporial tables)
EXEC sp_MSForEachTable '
 IF OBJECTPROPERTY(object_id(''?''), ''TableTemporalType'') = 2
  ALTER TABLE ? SET (SYSTEM_VERSIONING = OFF)
'
GO

-- Removing tables
EXEC sp_MSForEachTable 'DROP TABLE ?'
GO

Azure SQL +表(带约束)的模式与dbo + ipv6_database_firewall_rules条件不同。

这是一个小扩展https://stackoverflow.com/a/43128914/4510954的答案。

DECLARE @sql NVARCHAR(2000)

WHILE(EXISTS(SELECT 1 from INFORMATION_SCHEMA.TABLE_CONSTRAINTS WHERE CONSTRAINT_TYPE='FOREIGN KEY'))
BEGIN
    SELECT TOP 1 @sql=('ALTER TABLE ' + CONSTRAINT_SCHEMA + '.[' + TABLE_NAME + '] DROP CONSTRAINT [' + CONSTRAINT_NAME + ']')
    FROM INFORMATION_SCHEMA.TABLE_CONSTRAINTS
    WHERE CONSTRAINT_TYPE = 'FOREIGN KEY'
    EXEC(@sql)
    PRINT @sql
END

WHILE(EXISTS(SELECT * from INFORMATION_SCHEMA.TABLES WHERE TABLE_NAME != '__MigrationHistory' AND TABLE_NAME != 'database_firewall_rules' AND TABLE_NAME != 'ipv6_database_firewall_rules'))
BEGIN
    SELECT TOP 1 @sql=('DROP TABLE ' + CONSTRAINT_SCHEMA  + '.[' + TABLE_NAME + ']')
    FROM INFORMATION_SCHEMA.TABLE_CONSTRAINTS
    WHERE TABLE_NAME != '__MigrationHistory' AND TABLE_NAME != 'database_firewall_rules'
    EXEC(@sql)
    PRINT @sql
END

如果删除整个数据库,然后重新创建它呢?这对我很有用。

DROP DATABASE mydb;
CREATE DATABASE mydb;