[CASSANDRA-10783] Allow literal value as parameter of UDF & UDA

• Type: Improvement
• Status: Resolved
• Priority: Low
• Resolution: Fixed
• Fix Version/s: 3.8
• Component/s: Legacy/CQL
• Labels: CQL3 UDF doc-impacting
• Impacts: Clients
• Assignee: Sylvain Lebresne
• Reporter: DuyHai Doan

Authors

Sylvain Lebresne

Reviewers

Benjamin Lerer

• Created: 28/Nov/15 16:49
• Updated: 25/Apr/20 16:29
• Resolved: 15/Jun/16 07:41

Description

I have defined the following UDF

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;

I got the following error message:

SyntaxException: <ErrorMessage code=2000 [Syntax error in CQL query] message="line 1:19 no viable alternative at input '101' (SELECT maxOf(val1, [101]...)">

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>

Issue Links

• depends upon: CASSANDRA-7396 Allow selecting Map values and Set elements
• is depended upon by: CASSANDRA-11871 Allow to aggregate by time intervals
• is duplicated by: CASSANDRA-9243 Literals should be valid selectors in SELECT statements
• is duplicated by: CASSANDRA-9253 Bind markers should be allowed in function arguments of Selectors
• links to: Cassci
• links to: Git branch