清空数据库所有表数据，表和表结构约束都不变

有两个地方需要改,
第一行和最后一行的testdb改成你的数据库名

use testdb

declare @tablename varchar(max)
declare havetable cursor for  select [name] from sysobjects where xtype='U'
open havetable
fetch next from havetable into @tablename
WHILE @@FETCH_STATUS = 0
begin
    exec('delete from '+ @tablename)
    fetch next from havetable into @tablename
end
close havetable
deallocate havetable
DUMP TRANSACTION testdb WITH NO_LOG

use testdb

declare @tablename varchar(max)
declare havetable cursor for  select [name] from sysobjects where xtype='U'
open havetable
fetch next from havetable into @tablename
WHILE @@FETCH_STATUS = 0
begin  
    exec('delete from '+ @tablename)
    fetch next from havetable into @tablename
end
close havetable
deallocate havetable
DUMP TRANSACTION testdb WITH NO_LOG