在论坛碰到有人问到无法Attach数据库的问题,错误信息为:Msg5171,Level16,State1,Line2path\\allen_log.ldfisnotaprimarydatabasefile.很明显这个错误表示Attch
在论坛碰到有人问到无法Attach数据库的问题,错误信息为:
很明显这个错误表示Attch数据库选择的文件不是主数据库文件,但是看附加的数据文件确实是MDF结尾的。问用户是否有多个MDF文件,用户说是,但是他确定选择的文件肯定是主数据文件,不会有错。他认为数据库文件是损坏了,我很确信这个错误是因为选择的主数据文件不对。
用Profiler Trace抓了一下,网站空间,看到后台执行下面的语句:
declare @command nvarchar(300)
valuesql_variantNULL)
insert #smoPrimaryFileProp exec(@command)
里边使用了'dbcc checkprimaryfile,美国服务器,从网上查了一下这个DBCC命令可以查询Detach的数据库主数据文件信息,有四个选项可以使用:
0)
GO
1)
GO
2)
GO
3)
结果如下:
0表示文件是不是MDF文件
1最详细可以查询数据库文件大小增长文件ID
2显示数据库名称,内部版本号已经排序规则
3是1的缩减版结果
使用DBCC checkprimaryfile查询刚才附件的文件就报了上面的错误,所以确信这个MDF文件错误了,使用其他文件就可以正确附加。
其实解决这个问题没必要这么麻烦,几个MDF文件试一次就可以了。但是知道了这个命令,香港虚拟主机,以后想查询Detach数据库信息了,就非常容易了。
另外有一个好的命名习惯是很重要的,不要将所有的辅助文件也命名为MDF,应该为NDF或者自己制定规则。
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