[CASSANDRA-11805] Row deleted when value updated to null

• Type: Bug
• Status: Resolved
• Priority: Normal
• Resolution: Not A Problem
• Component/s: Legacy/Core

Environment

C* 3.5, both single node and cluster, C* 3.6 snapshot single node

• Severity: Normal
• Assignee: Unassigned
• Reporter: Jaroslav Kamenik
• Created: 14/May/16 17:02
• Updated: 16/Apr/19 09:30
• Resolved: 17/May/16 08:38

Description

It seems that the behaviour of the value update to null differs when row is created by insert or update. When it is inserted the row stays and the value is null, when updated the row is deleted.

Simple example:

Inserts:

create table aaa (a ascii, b ascii, c ascii, primary key (a,b));

insert into aaa (a,b,c) values ('a','b','c');
insert into aaa (a,b,c) values ('a','c','d');
insert into aaa (a,b,c) values ('a','d','e');

select * from aaa;

a | b | c
-----
a | b | c
a | c | d
a | d | e

update aaa set c = null where a='a' and b='b';

select * from aaa;

a | b | c
--------
a | b | null
a | c | d
a | d | e

Updates:

create table bbb (a ascii, b ascii, c ascii, primary key (a,b));

update bbb set c = 'c' where a='a' and b='b';
update bbb set c = 'd' where a='a' and b='c';
update bbb set c = 'e' where a='a' and b='d';

select * from bbb;

a | b | c
-----
a | b | c
a | c | d
a | d | e

update bbb set c = null where a='a' and b='b';

select * from bbb;

a | b | c
-----
a | c | d
a | d | e

Issue Links

• is duplicated by: CASSANDRA-14505 Removal of last element on a List deletes the entire row