[CASSANDRA-11339] WHERE clause in SELECT DISTINCT can be ignored

• Type: Bug
• Status: Resolved
• Priority: Normal
• Resolution: Fixed
• Fix Version/s: 2.2.x, 3.11.5
• Component/s: Legacy/CQL
• Severity: Normal
• Assignee: Alex Petrov
• Reporter: Philip Thompson

Authors

Alex Petrov

Reviewers

Benjamin Lerer

• Created: 10/Mar/16 19:02
• Updated: 01/Aug/21 11:28
• Resolved: 14/Apr/16 10:40

Description

I've tested this out on 2.1-head. I'm not sure if it's the same behavior on newer versions.

For a given table t, with PRIMARY KEY (id, v) the following two queries return the same result:
SELECT DISTINCT id FROM t WHERE v > X ALLOW FILTERING
SELECT DISTINCT id FROM t

The WHERE clause in the former is silently ignored, and all id are returned, regardless of the value of v in any row.

It seems like this has been a known issue for a while:
http://stackoverflow.com/questions/26548788/select-distinct-cql-ignores-where-clause

However, if we don't support filtering on anything but the partition key, we should reject the query, rather than silently dropping the where clause