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From Craig L Russell <Craig.Russ...@Sun.COM>
Subject Fwd: COUNT queries
Date Wed, 09 Nov 2005 18:42:43 GMT
Hi,

Is the behavior of COUNT(manager) (please see below) specified in SQL?

> "SELECT COUNT(manager) FROM Employee"

Thanks,

Craig

Begin forwarded message:

> From: Michael Watzek <mwa.tech@spree.de>
> Date: November 9, 2005 7:12:45 AM PST
> To: jdo-dev@db.apache.org
> Subject: COUNT queries
> Reply-To: jdo-dev@db.apache.org
>
>
> Hi,
>
> does COUNT in JDO consider NULL values? In SQL, NULL values are not  
> considered by COUNT.
>
> In JDO, does COUNT consider duplicates? In SQL, duplicates are  
> considered by COUNT.
>
> Our testdata has five employees. Four employees have the same  
> manager. One employee does not have a manager.
>
> What is the result of the following JDO query: "SELECT COUNT 
> (manager) FROM Employee"?
>
> Is the result 4?
>
> Regards,
> Michael
> -- 
> -------------------------------------------------------------------
> Michael Watzek                  Tech@Spree Engineering GmbH
> mailto:mwa.tech@spree.de        Buelowstr. 66
> Tel.:  ++49/30/235 520 36       10783 Berlin - Germany
> Fax.:  ++49/30/217 520 12       http://www.spree.de/
> -------------------------------------------------------------------
>

Craig Russell
Architect, Sun Java Enterprise System http://java.sun.com/products/jdo
408 276-5638 mailto:Craig.Russell@sun.com
P.S. A good JDO? O, Gasp!


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