[Koha-devel] Active borrowers report

[Galen Charlton]

Hi,

On 01/09/2012 03:30 PM, Mike Hafen wrote:
> I've seen UNION used to join those two tables in queries.  I'm
> imaginning something like:
>
> SELECT YEAR(issuedate), MONTH(issuedate), categorycode, COUNT(DISTINCT
> borrowernumber)
> FROM (
>    SELECT issuedate,categorycode,borrowernumber FROM old_issues
>   UNION ALL
>    SELECT issuedate,categorycode,borrowernumber FROM issues
>   )
> LEFT JOIN borrowers USING (borrowernumber)
> GROUP BY YEAR(issuedate), MONTH(issuedate), categorycode;

A UNION ALL is indeed a valid way to do it.

Regards,

Galen
-- 
Galen Charlton
Director of Support and Implementation
Equinox Software, Inc. / The Open Source Experts
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