Mailing-List: contact derby-dev-help@db.apache.org; run by ezmlm
Precedence: bulk
Reply-To: <derby-dev@db.apache.org>
Date: Thu, 13 Sep 2012 04:14:07 +1100 (NCT)
From: "Dag H. Wanvik (JIRA)" <jira@apache.org>
To: derby-dev@db.apache.org
Message-ID: <1337962831.70083.1347470047765.JavaMail.jiratomcat@arcas>
In-Reply-To: <1346960935.5633.1346152748045.JavaMail.jiratomcat@arcas>
Subject: [jira] [Commented] (DERBY-5911) WHERE condition getting pushed into
 sub-query with FETCH
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: 7bit


    [ https://issues.apache.org/jira/browse/DERBY-5911?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13454134#comment-13454134 ] 

Dag H. Wanvik commented on DERBY-5911:
--------------------------------------

Backported to 10.9 as svn 1384041.

                
> WHERE condition getting pushed into sub-query with FETCH
> --------------------------------------------------------
>
>                 Key: DERBY-5911
>                 URL: https://issues.apache.org/jira/browse/DERBY-5911
>             Project: Derby
>          Issue Type: Bug
>          Components: SQL
>    Affects Versions: 10.9.1.0
>         Environment: Tested with Derby 10.9.1.0 on Windows 7 x64, Java 1.6.0_27-b07 server
>            Reporter: Stefan Zeiger
>            Assignee: Dag H. Wanvik
>             Fix For: 10.9.1.1, 10.10.0.0
>
>         Attachments: derby5911a.diff, derby5911a.stat, derby5911b.diff, derby5911b.stat
>
>
> Derby pushes query conditions down into subqueries with FETCH limits, thus creating wrong results. Take the following snippet:
>     CREATE TABLE COFFEES (COF_NAME VARCHAR(254),PRICE INTEGER);
>     
>     INSERT INTO COFFEES (COF_NAME,PRICE) VALUES ('Colombian',       5);
>     INSERT INTO COFFEES (COF_NAME,PRICE) VALUES ('French_Roast',    5);
>     INSERT INTO COFFEES (COF_NAME,PRICE) VALUES ('Colombian_Decaf', 20);
>     
>     select COF_NAME, PRICE from COFFEES order by COF_NAME fetch next 2 rows only;
>     
>     select * from (
>       select COF_NAME, PRICE from COFFEES order by COF_NAME fetch next 2 rows only
>     ) t where t.PRICE < 10;
> The first query correctly returns the rows (Colombian,5), (Colombian_Decaf,20).
> The second query (which filters the result of the first one) returns (Colombian,5), (French_Roast,5). The row (French_Roast,5) should not be there since it is not a result of the first query. It shows up because (supposedly) the filter condition has been evaluated before the fetch limit.

--
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