How do you recommend I implement that feature in hbase? Regards,
Cheyenne O. Forbes On Wed, Aug 30, 2017 at 11:57 PM, Anoop John <[email protected]> wrote: > You cannot rely on postDelete for cells removed because of TTL.. > Because it is not a user started delete op and there wont be any > postDelete happening for this cell.. The cell is there in some > HFile. Even after the TTL time elapsed also.. When a read happens, > the read flow will filter out such cells from reaching client.. Also > if there been a compaction happened involving this file, the cell > would have got removed. So you can not really guarantee. > > -Anoop- > > On Wed, Aug 30, 2017 at 3:15 AM, Ted Yu <[email protected]> wrote: > > I wonder if you can make use of per Cell TTL ? > > > > See third paragraph under http://hbase.apache.org/book.html#ttl > > > > Basically there would be two flags (same row): one for marking whether > user > > has submitted the comment, the other is for the TTL you described. > > When postDelete() is called on the TTL'ed cell, you can retrieve the > first > > flag and make decision. > > > > FYI > > > > On Mon, Aug 28, 2017 at 10:31 PM, Cheyenne Forbes < > > [email protected]> wrote: > > > >> I'm sorry, "*postDelete*" wasnt supposed to be a link, I copied the text > >> and gmail sent it as a link. > >> > >> *Use case:* > >> > >> When a user is commenting with a photo it is uploaded to be able to be > >> previewed and the id of the photo is added to a hbase table "tempFiles" > >> with a 5 hour TTL for each row, if the user submits the comment, the > row is > >> deleted manually and *postDelete* would "ignore" it but if it isnt > >> submitted and the TTL reaches, *postDelete* would run a piece of code > which > >> would delete the file from my file server > >> > >> > >> On Mon, Aug 28, 2017 at 5:33 PM, Ted Yu <[email protected]> wrote: > >> > >> > There is no such indication from the book you mentioned. > >> > Can you tell us your use case where such distinction is needed ? > >> > -------- Original message --------From: Cheyenne Forbes < > >> > [email protected]> Date: 8/28/17 2:51 PM (GMT-08:00) > To: > >> > [email protected] Subject: Co-processors: Know if row is being > >> > deleted by TTL > >> > Is is possible to know if a row is being deleted manually or by the > >> > reaching of the TTL on "*postDelete > >> > <https://hbase.apache.org/0.94/apidocs/org/apache/hadoop/ > >> > hbase/coprocessor/BaseRegionObserver.html# > postDelete(org.apache.hadoop. > >> > hbase.coprocessor.ObserverContext,%20org.apache. > >> > hadoop.hbase.client.Delete,%20org.apache.hadoop.hbase. > >> > regionserver.wal.WALEdit,%20boolean)>* > >> > "? > >> > > >> > Regards, > >> > > >> > Cheyenne O. Forbes > >> > > >> >
