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Date: Fri, 6 Feb 2015 14:50:37 +0000
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 <CAFqWSgdnspPCouVhJk_oBh0TBRp=HFZtB8JQrLQEHmRWn8WhPA@mail.gmail.com>
Subject: Re: Conditional Update Code?
From: Benedict Elliott Smith <belliottsmith@datastax.com>
To: dev@cassandra.apache.org
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It's quite possible support could be added to evaluate a UDF as part of the
condition check. The code you're looking for are implementors of
CASRequest.appliesTo(), in CQL3CasRequest and
CassandraServer.ThriftCASRequest

It seems like https://issues.apache.org/jira/browse/CASSANDRA-8488 would
offer the basic functionality, except that it is expected to require ALLOW
FILTERING, which is unlikely to be permitted for a CAS operation, since the
implication is that the work is too expensive for normal use. Such a
constraint is probably not necessary if a clustering prefix is provided,
though (i.e. a full CQL row key).

On Fri, Feb 6, 2015 at 2:38 PM, Brian O'Neill <bone@alumni.brown.edu> wrote=
:

>
> All,
>
> I=C2=B9m just looking for a little direction=C5=A0
>
> Anyone know where I can find the code that checks the condition in a
> conditional update?
> We=C2=B9d love to have more expressive conditions, beyond just equality. =
 (e.g.
> column contains? value)
>
> I wanted to see how hard this would be to contribute.
> Is such a JIRA already open?
>
> -brian
>
> ---
> Brian O'Neill
> Chief Technology Officer
> Health Market Science, a LexisNexis Company
> 215.588.6024 Mobile =E2=82=AC @boneill42 <http://www.twitter.com/boneill4=
2>
>
>
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