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From Curt Allred <c...@mediosystems.com>
Subject RE: will compaction delete empty rows after all columns expired?
Date Fri, 25 May 2012 18:21:24 GMT
This is an old thread from December 27, 2011.  I interpret the "yes" answer to mean you do
not have to explicitly delete an empty row after all of its columns have been deleted, the
empty row (i.e. row key) will automatically be deleted eventually (after gc_grace).  Is that
true?   I am not seeing that behavior on our v 0.7.9 ring.  We are accumulating a large number
of old empty rows.  They are taking alot of space because the row keys are big, and exploding
the data size by 10x.  I have read conflicting information on blogs and cassandra docs.  Someone
mentioned that there are both row tombstones and column tombstones, implying that you have
to explicitly delete empty rows.  Is that correct.

My basic question is... how do I delete all these empty row keys?

-----------------------------
From: Feng Qu
Sent: Tuesday, December 27, 2011 11:09 AM
Compaction should delete empty rows once gc_grace_seconds is passed, right? 
-----------------------------
From: Peter Schuller
Yes.  
But just to be extra clear: Data will not actually be removed once the row in question participates
in compaction. Compactions will not be actively triggered by Cassandra for tombstone processing
reasons.

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