Hi, Ram and Anoop, Thanks for the nice reference on the java file, which I will check through.
It is interesting to know about the recent feature on preCompactScannerOpen() hook. Ram, it would be nice if I can know how to specify conditions like c1 = 'a'. I have also checked the example code in hbase 6496 link <https://issues.apache.org/jira/browse/HBASE-6496>. which show how to delete data before time as in a on-demand specification... Cheers, Yun On Wed, Oct 17, 2012 at 8:46 AM, Ramkrishna.S.Vasudevan < ramkrishna.vasude...@huawei.com> wrote: > Also to see the code how the delete happens pls refer to StoreScanner.java > and how the ScanQueryMatcher.match() works. > > That is where we decide if any kv has to be avoided due to already deleted > tombstone marker. > > Forgot to tell you about this. > > Regards > Ram > > > -----Original Message----- > > From: yun peng [mailto:pengyunm...@gmail.com] > > Sent: Wednesday, October 17, 2012 5:54 PM > > To: user@hbase.apache.org > > Subject: Where is code in hbase that physically delete a record? > > > > Hi, All, > > I want to find internal code in hbase where physical deleting a record > > occurs. > > > > -some of my understanding. > > Correct me if I am wrong. (It is largely based on my experience and > > even > > speculation.) Logically deleting a KeyValue data in hbase is performed > > by > > marking tombmarker (by Delete() per records) or setting TTL/max_version > > (per Store). After these actions, however, the physical data are still > > there, somewhere in the system. Physically deleting a record in hbase > > is > > realised by *a scanner to discard a keyvalue data record* during the > > major_compact. > > > > -what I need > > I want to extend hbase to associate some actions with physically > > deleting a > > record. Does hbase provide such hook (or coprocessor API) to inject > > code > > for each KV record that is skipped by hbase storescanner in > > major_compact. > > If not, anyone knows where should I look into in hbase (-0.94.2) for > > such > > code modification? > > > > Thanks. > > Yun > >
