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https://issues.apache.org/jira/browse/CASSANDRA-7461?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15310417#comment-15310417
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Sylvain Lebresne commented on CASSANDRA-7461:
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Do you think there is that much difference between those to justify spitting
it? I mean, I don't mind it in principle, but I feel it'll just split the
discussion on what feels to me like essentially the same thing, and will create
arbitrary dependencies between the patches.
Overall, I strongly feel that operator should just be syntactic sugar native
functions. In particular, on the grammar side, I'd let operators act between
any 2 terms, and so supporting {{+}} on numbers or on strings will be the same
outside of dispatching to different (trivial) methods based on the type.
The main issue I see on this ticket is that our current type system is
necessarily up to the task, at least not if we want a good user experience,
mainly due to the fact that we'll need multiple overload of the operator
functions for every type (typically a {{add(int, int)}}, {{add(bigint,
bigint)}}, ....) and that if we do that currently, things like {{add(2, 3)}}
won't type-check because it will complain that multiple overload could apply
(true) and that it can't make a choice. This problem is not really specific
related to operators however, it's more about how we make functions resolution
when there is overloads smarter (which I think we can do but I'll let that
discussion for another comment) and if anything, it's that part that I would
split in a separate ticket (since again, it's not specific to operators, even
if operators are a good motivation for the improvement).
> operator functionality in CQL
> -----------------------------
>
> Key: CASSANDRA-7461
> URL: https://issues.apache.org/jira/browse/CASSANDRA-7461
> Project: Cassandra
> Issue Type: New Feature
> Components: CQL
> Reporter: Robert Stupp
> Assignee: Benjamin Lerer
> Labels: cql
>
> Intention: Allow operators in CQL
> Operators could be decimal arithmetics {{+ - * /}} or boolen arithmetics {{|
> & !}} or string 'arithmetics' {{+}}
> {{SELECT tab.label + ' = ' + tab.value FROM foo.tab}}
> {{SELECT * FROM tab WHERE tab.label + ' = ' + tab.value = 'foo = bar'}}
> as well as
> {{CREATE INDEX idx ON tab ( tab.tabel + '=' + tab.value )}}
> or
> {{CREATE INDEX idx ON tab (label) WHERE contains(tab.tabel,
> 'very-important-key')}}
> Operators could be mapped to UDFs like this:
> {{+}} mapped to UDF {{cstarstd::oper_plus(...)}}
> {{-}} mapped to UDF {{cstarstd::oper_minus(...)}}
> or handled directly via {{Cql.g}} in 'special' code
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