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HomeDatabaseMysql Tutorial清空数据库中所有表记录,记录ID恢复从0开始

近来发现数据库过大,空间不足,因此打算将数据库的数据进行全面的清理,但表非常多,一张一张的清空,实在麻烦,因此就想利用SQL语句一次清空所有数据.找到了三种方法进行清空.使用的数据库为MS SQL SERVER. 1.搜索出所有表名,构造为一条SQL语句 declare @trun_na

   近来发现数据库过大,空间不足,因此打算将数据库的数据进行全面的清理,但表非常多,一张一张的清空,实在麻烦,因此就想利用SQL语句一次清空所有数据.找到了三种方法进行清空.使用的数据库为MS SQL SERVER.

  1.搜索出所有表名,构造为一条SQL语句

  declare @trun_name varchar(8000)

  set @trun_name=''

  select @trun_name=@trun_name + 'truncate table ' + [name] + ' ' from sysobjects where xtype='U' and status > 0

  exec (@trun_name)

  该方法适合表不是非常多的情况,否则表数量过多,超过字符串的长度,不能进行完全清理.

  2.利用游标清理所有表

  declare @trun_name varchar(50)

  declare name_cursor cursor for

  select 'truncate table ' + name from sysobjects where xtype='U' and status > 0

  open name_cursor

  fetch next from name_cursor into @trun_name

  while @@FETCH_STATUS = 0

  begin

  exec (@trun_name)

  print 'truncated table ' + @trun_name

  fetch next from name_cursor into @trun_name

  end

  close name_cursor

  deallocate name_cursor

  这是我自己构造的,可以做为存储过程调用, 能够一次清空所有表的数据,并且还可以进行有选择的清空表.

  3.利用微软未公开的存储过程

  exec sp_msforeachtable "truncate table ?"

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