[jira] [Comment Edited] (CASSANDRA-11805) Row deleted when value updated to null

["Sylvain Lebresne (JIRA)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/CASSANDRA-11805?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15286245#comment-15286245 ] 

Sylvain Lebresne edited comment on CASSANDRA-11805 at 5/17/16 8:55 AM:
-----------------------------------------------------------------------

Well, if you want to absolutely ensure that the row stays but the value for that column is null, you can always batch your update with an insert on the primary key columns only, so in your example:
{noformat}
BEGIN BATCH;
  INSERT INTO bbb(a, b) VALUES ('a', 'b');
  UPDATE bbb SET c = null WHERE a='a' AND b='b';
APPLY BATCH
{noformat}


was (Author: slebresne):
Well, if you want to absolutely ensure that the row stays but the value for that column is null, you can always batch your update with an insert on the primary key columns only, so in your example:
{{noformat}}
BEGIN BATCH;
  INSERT INTO bbb(a, b) VALUES ('a', 'b');
  UPDATE bbb SET c = null WHERE a='a' AND b='b';
APPLY BATCH
{{noformat}}

> Row deleted when value updated to null
> --------------------------------------
>
>                 Key: CASSANDRA-11805
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-11805
>             Project: Cassandra
>          Issue Type: Bug
>          Components: Core
>         Environment: C* 3.5, both single node and cluster, C* 3.6 snapshot single node
>            Reporter: Jaroslav Kamenik
>
> 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



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)