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From Michael Watzek <mwa.t...@spree.de>
Subject COUNT queries
Date Wed, 09 Nov 2005 15:12:45 GMT

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?

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/

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