[CASSANDRA-17628] CQL writetime and ttl functions should be forbidden for multicell columns

• Type: Bug
• Status: Resolved
• Priority: Normal
• Resolution: Fixed
• Fix Version/s: 3.0.28, 3.11.14, 4.0.5, 4.1-alpha1, 4.1, 5.0-alpha1, 5.0
• Component/s: CQL/Semantics
• Bug Category: Correctness - API / Semantic Definition
• Severity: Normal
• Complexity: Low Hanging Fruit
• Discovered By: Adhoc Test
• Platform: All
• Since Version: 2.1.13

Source Control Link

https://github.com/apache/cassandra/commit/09692d5a58d96089c699f59e9b7daacd066e902d

Test and Documentation Plan

New tests are included

• Assignee: Andres de la Peña
• Reporter: Andres de la Peña

Authors

Andres de la Peña

Reviewers

Berenguer Blasi

• Created: 16/May/22 10:16
• Updated: 12/Sep/23 13:02
• Resolved: 27/Jun/22 14:34

Description

CQL writetime and ttl functions are currently forbidden for collections, frozen or not. Also, they are always allowed for UDTs, frozen or not:

CREATE TYPE udt (a int, b int);
CREATE TABLE t (k int PRIMARY KEY, s set<int>, fs frozen<set<int>>, t udt, ft frozen<udt>);

SELECT writetime(s) FROM t; -- fails
SELECT writetime(st) FROM t; -- fails
SELECT writetime(t) FROM t; -- allowed
SELECT writetime(ft) FROM t; -- allowed

This is done by checking in Selectable.WritetimeOrTTL#newSelectorFactory whether the column is a collection or not. However, I think that what we should check is whether the column is multi-cell. That way the function would work with frozen collections and UDTs, and it would reject unfrozen collections and UDTs:

SELECT writetime(s) FROM t; -- fails
SELECT writetime(st) FROM t; -- allowed
SELECT writetime(t) FROM t; -- fails
SELECT writetime(ft) FROM t; -- allowed

Issue Links

• Blocked: CASSANDRA-17681 CQL function writetime should not be allowed to apply on UDT columns
• Discovered while testing: CASSANDRA-17425 Add new CQL function maxWritetime
• is related to: CASSANDRA-8877 Ability to read the TTL and WRITE TIME of an element in a collection