db-derby-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Knut Anders Hatlen (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (DERBY-6017) IN lists with mixed types may return wrong results
Date Thu, 20 Dec 2012 21:45:12 GMT

    [ https://issues.apache.org/jira/browse/DERBY-6017?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13537406#comment-13537406
] 

Knut Anders Hatlen commented on DERBY-6017:
-------------------------------------------

Thanks for looking at the patch, Bryan.

I'll look into the other data types and see if I find similar problems. If promoting a REAL
to a DOUBLE could cause loss of precision (can it?), they might show the same problem. Promoting
an INT to a REAL could lose precision too, but I think we always promote to DOUBLE when mixing
INTs and REALs (per [1]). It's worth testing, though.

[1] http://db.apache.org/derby/docs/10.9/ref/rrefsqlj27767.html
                
> IN lists with mixed types may return wrong results
> --------------------------------------------------
>
>                 Key: DERBY-6017
>                 URL: https://issues.apache.org/jira/browse/DERBY-6017
>             Project: Derby
>          Issue Type: Bug
>          Components: SQL
>    Affects Versions: 10.9.1.0
>            Reporter: Knut Anders Hatlen
>            Assignee: Knut Anders Hatlen
>         Attachments: d6017-1a-duplicates.diff
>
>
> Given this table:
> ij> connect 'jdbc:derby:memory:db;create=true';
> ij> create table t(x bigint);
> 0 rows inserted/updated/deleted
> ij> insert into t values 9223372036854775805, 9223372036854775806, 9223372036854775807;
> 3 rows inserted/updated/deleted
> A query that uses an IN list that contains all the three values actually stored in the
table, returns all three rows as expected:
> ij> select * from t where x in (9223372036854775805, 9223372036854775806, 9223372036854775807);
> X                   
> --------------------
> 9223372036854775805 
> 9223372036854775806 
> 9223372036854775807 
> 3 rows selected
> However, if we add a value whose type precedence is higher, like a DOUBLE value, and
that value happens to be equal to the approximation of the other values in the IN list when
they are cast from BIGINT to DOUBLE, only one row is returned:
> ij> select * from t where x in (9223372036854775805, 9223372036854775806, 9223372036854775807,
9.223372036854776E18);
> X                   
> --------------------
> 9223372036854775805 
> 1 row selected
> I believe this query should return all three rows too.

--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators
For more information on JIRA, see: http://www.atlassian.com/software/jira

Mime
View raw message