We looking for solution for same problem. We have a wide column family with counters and we want to delete old data like 1 months old. One of potential ideas was to implement hook in compaction code and drop column which we don't need. Is this a viable option?
From: aaron morton Sent: Tuesday, February 12, 2013 9:01 AM To: Subject: Re: Deleting old items
So is it possible to delete all the data inserted in some CF between 2 dates or data older than 1 month ?
You need to issue row level deletes. If you don't know the row key you'll need to do range scans to locate them.
If you are deleting parts of wide rows consider reducing the min_compaction_level_threshold on the CF to 2
Aaron Morton
Freelance Cassandra Developer
Ilya Grebnov's gravatar image asked Feb 13 2013 at 10:08 in Cassandra-User by Ilya Grebnov

2 Answers

That's what the TTL does.
Manually delete all the older data now, then start using TTL.
----------------- Aaron Morton Freelance Cassandra Developer New Zealand
@aaronmorton http://www.thelastpickle.com
aaron morton's gravatar image answered Feb 17 2013 at 17:16 by aaron morton
According to https://issues.apache.org/jira/browse/CASSANDRA-2103 There is no support for time to live (TTL) on counter columns. Did I miss something?
From: aaron morton Sent: Sunday, February 17, 2013 9:16 AM To: Subject: Re: Deleting old items during compaction (WAS: Deleting old items)
That's what the TTL does.
Manually delete all the older data now, then start using TTL.
Aaron Morton
Freelance Cassandra Developer
Ilya Grebnov's gravatar image answered Feb 17 2013 at 21:43 by Ilya Grebnov

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