Home | About | Sematext search-lucene.com search-hadoop.com
 Search Hadoop and all its subprojects:

Switch to Threaded View
HBase >> mail # user >> delete rows without writing HLog may be appear in the future?


Copy link to this message
-
Re: delete rows without writing HLog may be appear in the future?
In our apps, deletes will be frequent, and it occurs to each records every
time, if write hlog, the performance and response will be low. In fact,we
can bear with some records with delete fail, but recently I have found more
records delete some time ago, for example, one week , they reappear
again.Then, that makes me curious about what should do next., delete with
writing hlog, or put without hlog....
On Nov 21, 2012 11:19 PM, "Kevin O'dell" <[EMAIL PROTECTED]> wrote:

> Bing,
>
>   I am curious to hear more about Mike's question.  Why are you not using
> the WAL for your deletes?
>
> On Wed, Nov 21, 2012 at 10:17 AM, Bing Jiang <[EMAIL PROTECTED]
> >wrote:
>
> > yes,hbase has made a compaction between batch-put and deletes. any ideas?
> >
> > On Nov 21, 2012 11:10 PM, "Michael Segel" <[EMAIL PROTECTED]>
> > wrote:
> > >
> > > Some time later?
> > >
> > > Time of course is relative, so I have to ask what occurred between the
> > write and the delete?
> > > How much time? Did you have any compactions in between the write and
> the
> > delete?
> > >
> > > Why are you not consistent in your use of the WAL ?
> > >
> > >
> > > On Nov 21, 2012, at 6:37 AM, Bing Jiang <[EMAIL PROTECTED]>
> > wrote:
> > >
> > > > hi,all.
> > > > I want to describe a phenomenon that happens to our hbase cluster.
> > > > I use puts(List<Put>) to insert many records with writing hlog
> enable,
> > > > and some time later I delete all of these records with writing hlog
> > disable.
> > > > When one week later, i scan the table, I found some records I have
> > delete
> > > > reappear again.
> > > > It is an interesting case. In my opinion, if we delete data without
> > enable
> > > > writing hlog, when regionserver fails, the log will replay in another
> > > > regionserver.
> > > > Can anyone tell me if I persist on deleting records without enable
> > writing
> > > > hlog, is there a way to prevent these records from reappearing again
> > some
> > > > time later?
> > > >
> > > > Cheers!
> > > > --
> > > > Bing Jiang
> > > > weibo: http://weibo.com/jiangbinglover
> > > > BLOG: http://blog.sina.com.cn/jiangbinglover
> > > > BLOG: http://www.binospace.com
> > > > National Research Center for Intelligent Computing Systems
> > > > Institute of Computing technology
> > > > Graduate University of Chinese Academy of Science
> > >
> >
>
>
>
> --
> Kevin O'Dell
> Customer Operations Engineer, Cloudera
>