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From Sylvain Lebresne <sylv...@datastax.com>
Subject Re: time to live rows
Date Tue, 08 Feb 2011 16:02:18 GMT
>
> I hope you don't consider this a hijack of the thread...
>
> What I'd like to know is the following:
>
> The GC removes TTL rows some time after they expire, at its convenience.
> But will they stop being returned as soon as they expire? (This is the
> expected behavior...)
>

It is the individual column that have TTL. When a column expires, it becomes
a delete tombstone. Now, a row with tombstones (even only them) will show
during range request. But the explanation is here:
http://wiki.apache.org/cassandra/FAQ#range_ghosts


>
> On Tue, Feb 8, 2011 at 5:11 PM, Kallin Nagelberg <
> kallin.nagelberg@gmail.com> wrote:
>
>> So the empty row will be ultimately removed then? Is there a way to
>> for the GC to verify this?
>>
>> Thanks,
>> -Kal
>>
>> On Tue, Feb 8, 2011 at 2:21 AM, Stu Hood <stuhood@gmail.com> wrote:
>> > The expired columns were converted into tombstones, which will live for
>> the
>> > GC timeout. The "empty" row will be cleaned up when those tombstones are
>> > removed.
>> > Returning the empty row is unfortunate... we'd love to find a more
>> > appropriate solution that might not involve endless scanning.
>> > See
>> > http://wiki.apache.org/cassandra/FAQ#i_deleted_what_gives
>> > http://wiki.apache.org/cassandra/FAQ#range_ghosts
>> >
>> > On Mon, Feb 7, 2011 at 1:49 PM, Kallin Nagelberg
>> > <kallin.nagelberg@gmail.com> wrote:
>> >>
>> >> I also tried forcing a major compaction on the column family using JMX
>> >> but the row remains.
>> >>
>> >> On Mon, Feb 7, 2011 at 4:43 PM, Kallin Nagelberg
>> >> <kallin.nagelberg@gmail.com> wrote:
>> >> > I tried that but I still see the row coming back on a list
>> >> > <columnfamily> in the CLI. My concern is that there will be a
pointer
>> >> > to an empty row for all eternity.
>> >> >
>> >> > -Kal
>> >> >
>> >> > On Mon, Feb 7, 2011 at 4:38 PM, Aaron Morton <
>> aaron@thelastpickle.com>
>> >> > wrote:
>> >> >> Deleting all the columns in a row via TTL has the same affect as
>> >> >> deleting th
>> >> >> row, the data will physically by removed during compaction.
>> >> >>
>> >> >> Aaron
>> >> >>
>> >> >>
>> >> >> On 08 Feb, 2011,at 10:24 AM, Bill Speirs <bill.speirs@gmail.com>
>> wrote:
>> >> >>
>> >> >> I don't think this is supported (but I could be completely wrong).
>> >> >> However, I'd love to see this functionality as well.
>> >> >>
>> >> >> How would one go about requesting such a feature?
>> >> >>
>> >> >> Bill-
>> >> >>
>> >> >> On Mon, Feb 7, 2011 at 4:15 PM, Kallin Nagelberg
>> >> >> <kallin.nagelberg@gmail.com> wrote:
>> >> >>> Hey,
>> >> >>>
>> >> >>> I have read about the new TTL columns in Cassandra 0.7. In
my case
>> I'd
>> >> >>> like to expire an entire row automatically after a certain
amount
>> of
>> >> >>> time. Is this possible as well?
>> >> >>>
>> >> >>> Thanks,
>> >> >>> -Kal
>> >> >>>
>> >> >>
>> >> >
>> >
>> >
>>
>
>

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