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https://issues.apache.org/jira/browse/CASSANDRA-10783?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15031159#comment-15031159
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Robert Stupp commented on CASSANDRA-10783:
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The problem is to choose the "right" function even if there are overloads.
({{CREATE FUNCTION foo(a int) ...}}, {{CREATE FUNCTION foo(a bigint) ...}},
{{CREATE FUNCTION foo(a smallint) ...}}, {{CREATE FUNCTION foo(a varint) ...}}).
I.e. we don't know _for sure_ that there will _always_ be just an int. In other
words: the result must be the same whenever you prepare the statement. Or: the
statement must not become ambiguous if you overload a function.
(This may become even more complicated/ambiguous if there's just use a bind
parameter.)
> Allow literal value as parameter of UDF & UDA
> ---------------------------------------------
>
> Key: CASSANDRA-10783
> URL: https://issues.apache.org/jira/browse/CASSANDRA-10783
> Project: Cassandra
> Issue Type: Improvement
> Components: CQL
> Reporter: DOAN DuyHai
> Assignee: Robert Stupp
> Priority: Minor
> Fix For: 3.x
>
>
> I have defined the following UDF
> {code:sql}
> CREATE OR REPLACE FUNCTION maxOf(current int, testValue int) RETURNS NULL ON
> NULL INPUT
> RETURNS int
> LANGUAGE java
> AS 'return Math.max(current,testValue);'
> CREATE TABLE maxValue(id int primary key, val int);
> INSERT INTO maxValue(id, val) VALUES(1, 100);
> SELECT maxOf(val, 101) FROM maxValue WHERE id=1;
> {code}
> I got the following error message:
> {code}
> SyntaxException: <ErrorMessage code=2000 [Syntax error in CQL query]
> message="line 1:19 no viable alternative at input '101' (SELECT maxOf(val1,
> [101]...)">
> {code}
> It would be nice to allow literal value as parameter of UDF and UDA too.
> I was thinking about an use-case for an UDA groupBy() function where the end
> user can *inject* at runtime a literal value to select which aggregation he
> want to display, something similar to GROUP BY ... HAVING <filter clause>
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