If you mean that multiple tombstones for the same row or column should be merged into a single one at compaction time, then yes, that is what happens.
On Tue, Jan 18, 2011 at 7:53 PM, Germán Kondolf <german.kond...@gmail.com> wrote: > Maybe it could be taken into account when the compaction is executed, > if I only have a consecutive list of uninterrupted tombstones it could > only care about the first. It sounds like the-way-it-should-be, maybe > as a part of the "row-reduce" process. > > Is it feasible? Looking into the CASSANDRA-1074 sounds like it should. > > //GK > http://twitter.com/germanklf > http://code.google.com/p/seide/ > > On Tue, Jan 18, 2011 at 10:55 AM, Sylvain Lebresne <sylv...@riptano.com> > wrote: >> On Tue, Jan 18, 2011 at 2:41 PM, David Boxenhorn <da...@lookin2.com> wrote: >>> Thanks, Aaron, but I'm not 100% clear. >>> >>> My situation is this: My use case spins off rows (not columns) that I no >>> longer need and want to delete. It is possible that these rows were never >>> created in the first place, or were already deleted. This is a very large >>> cleanup task that normally deletes a lot of rows, and the last thing that I >>> want to do is create tombstones for rows that didn't exist in the first >>> place, or lengthen the life on disk of tombstones of rows that are already >>> deleted. >>> >>> So the question is: before I delete, do I have to retrieve the row to see if >>> it exists in the first place? >> >> Yes, in your situation you do. >> >>> >>> >>> >>> On Tue, Jan 18, 2011 at 11:38 AM, Aaron Morton <aa...@thelastpickle.com> >>> wrote: >>>> >>>> AFAIK that's not necessary, there is no need to worry about previous >>>> deletes. You can delete stuff that does not even exist, neither >>>> batch_mutate >>>> or remove are going to throw an error. >>>> All the columns that were (roughly speaking) present at your first >>>> deletion will be available for GC at the end of the first tombstones life. >>>> Same for the second. >>>> Say you were to write a col between the two deletes with the same name as >>>> one present at the start. The first version of the col is avail for GC >>>> after >>>> tombstone 1, and the second after tombstone 2. >>>> Hope that helps >>>> Aaron >>>> On 18/01/2011, at 9:37 PM, David Boxenhorn <da...@lookin2.com> wrote: >>>> >>>> Thanks. In other words, before I delete something, I should check to see >>>> whether it exists as a live row in the first place. >>>> >>>> On Tue, Jan 18, 2011 at 9:24 AM, Ryan King <r...@twitter.com> wrote: >>>>> >>>>> On Sun, Jan 16, 2011 at 6:53 AM, David Boxenhorn <da...@lookin2.com> >>>>> wrote: >>>>> > If I delete a row, and later on delete it again, before GCGraceSeconds >>>>> > has >>>>> > elapsed, does the tombstone live longer? >>>>> >>>>> Each delete is a new tombstone, which should answer your question. >>>>> >>>>> -ryan >>>>> >>>>> > In other words, if I have the following scenario: >>>>> > >>>>> > GCGraceSeconds = 10 days >>>>> > On day 1 I delete a row >>>>> > On day 5 I delete the row again >>>>> > >>>>> > Will the tombstone be removed on day 10 or day 15? >>>>> > >>>> >>> >>> >> > -- Jonathan Ellis Project Chair, Apache Cassandra co-founder of Riptano, the source for professional Cassandra support http://riptano.com
