SQL- Module Adhérents

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SELECT YEAR (issuedate) AS ANNEE, categorycode AS CATEGORIE, COUNT(DISTINCT borrowernumber) AS NB_LECTEURS FROM ( SELECT issuedate, borrowernumber FROM old_issues UNION ALL SELECT issuedate, borrowernumber FROM issues ) AS all_issues LEFT JOIN borrowers USING (borrowernumber) GROUP BY CATEGORIE WITH ROLLUP Cette […]