[ https://issues.apache.org/jira/browse/CASSANDRA-8053?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14195994#comment-14195994
]
Robert Stupp commented on CASSANDRA-8053:
-----------------------------------------
forgot to mention:
Via {{state-type}} and {{final-type}} people can use UDT or tuple types or collections (see
CASSANDRA-7563) for the state - so they have plenty of room for their temporary data.
It's discussable whether we should allow some "generic" {{any}} type for the {{state-type}},
if {{final-type}} is present - for example to allow people to use e.g. {{java.util.HashMap}}
as the state variable type. Could be expressed by omitting {{STYPE <type>}} and requiring
{{FINALFUNC}} + {{FINALTYPE <type>}} then.
The state is always passed as a parameter named {{state}} into the state and final functions.
> Support for user defined aggregate functions
> --------------------------------------------
>
> Key: CASSANDRA-8053
> URL: https://issues.apache.org/jira/browse/CASSANDRA-8053
> Project: Cassandra
> Issue Type: New Feature
> Reporter: Robert Stupp
> Assignee: Robert Stupp
> Labels: cql, udf
> Fix For: 3.0
>
>
> CASSANDRA-4914 introduces aggregate functions.
> This ticket is about to decide how we can support "user defined aggregate functions".
UD aggregate functions should be supported for all UDF flavors (class, java, jsr223).
> Things to consider:
> * Special implementations for each scripting language should be omitted
> * No exposure of internal APIs (e.g. {{AggregateFunction}} interface)
> * No need for users to deal with serializers / codecs
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
|