db-derby-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Rick Hillegas (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (DERBY-5875) Derby returns wrong results when you set the ESCAPE character to NULL in a LIKE clause.
Date Mon, 23 Jul 2012 13:37:36 GMT

    [ https://issues.apache.org/jira/browse/DERBY-5875?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13420652#comment-13420652
] 

Rick Hillegas commented on DERBY-5875:
--------------------------------------

Hi Knut. Yes, I agree. If the LIKE pattern is set to NULL, that is supposed to cause the whole
LIKE clause to evaluate to NULL, not to raise an exception. This is required by the same rule
in the SQL Standard: part 2, section 8.5 <like predicate>, general rule 3.a.ii. Thanks.
                
> Derby returns wrong results when you set the ESCAPE character to NULL in a LIKE clause.
> ---------------------------------------------------------------------------------------
>
>                 Key: DERBY-5875
>                 URL: https://issues.apache.org/jira/browse/DERBY-5875
>             Project: Derby
>          Issue Type: Bug
>          Components: SQL
>    Affects Versions: 10.10.0.0
>            Reporter: Rick Hillegas
>
> The LIKE clause is supposed to evaluate to NULL if the optional ESCAPE character is set
to NULL. Instead, Derby treats this condition as equivalent to omitting the ESCAPE clause.
This violates part 2 of the SQL Standard, section 8.5 <like predicate>, general rule
3.a.ii.
> Thanks to Knut for disclosing this problem via the following script:
> connect 'jdbc:derby:memory:db;create=true';
> prepare ps as 'select tablename from sys.systables where tablename like ''SYSD%'' escape
?';
> -- should return no rows, but actually returns 2
> execute ps using 'values cast( null as char(1) )'; 

--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators: https://issues.apache.org/jira/secure/ContactAdministrators!default.jspa
For more information on JIRA, see: http://www.atlassian.com/software/jira

        

Mime
View raw message