9 Jan
2012
9 Jan
'12
9:41 p.m.
Awesome! Thank you, Mike -- seems to work perfectly! Cheers, Cab Vinton, Director Sanbornton Public Library Sanbornton, NH "Politeness and consideration for others is like investing pennies and getting dollars back." Thomas Sowell 2012/1/9 Mike Hafen <mdhafen@tech.washk12.org>:
SELECT YEAR(issuedate), MONTH(issuedate), categorycode, COUNT(DISTINCT borrowernumber) FROM ( SELECT issuedate, borrowernumber FROM old_issues UNION ALL SELECT issuedate, borrowernumber FROM issues ) AS all_issues
LEFT JOIN borrowers USING (borrowernumber) GROUP BY YEAR(issuedate), MONTH(issuedate), categorycode