如果我有一个类似这样的MySQL表格：
company_name action pagecount ------------------------------- Company A PRINT 3 Company A PRINT 2 Company A PRINT 3 Company B EMAIL Company B PRINT 2 Company B PRINT 2 Company B PRINT 1 Company A PRINT 3
能否运行一个MySQL查询以获得如下输出：
company_name EMAIL PRINT 1 pages PRINT 2 pages PRINT 3 pages ------------------------------------------------------------- CompanyA 0 0 1 3 CompanyB 1 1 2 0
这个想法是，页面计数可以变化，因此输出的列数量应该反映这一点，每个动作/页面计数对应一个列，然后统计每个公司名称的点击次数。我不确定这是否被称为数据透视表，但有人建议过这样做。
Copyright 2014-2026 https://www.php.cn/ All Rights Reserved | php.cn | 湘ICP备2023035733号
2
1145
收藏
我的解决方案是使用T-SQL而不是任何数据透视表：
SELECT CompanyName, SUM(CASE WHEN (action='EMAIL') THEN 1 ELSE 0 END) AS Email, SUM(CASE WHEN (action='PRINT' AND pagecount=1) THEN 1 ELSE 0 END) AS Print1Pages, SUM(CASE WHEN (action='PRINT' AND pagecount=2) THEN 1 ELSE 0 END) AS Print2Pages, SUM(CASE WHEN (action='PRINT' AND pagecount=3) THEN 1 ELSE 0 END) AS Print3Pages FROM Company GROUP BY CompanyName