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是否可以运行一个MySQL查询来获得如下输出：
company_name EMAIL PRINT 1页 PRINT 2页 PRINT 3页 ------------------------------------------------------------- CompanyA 0 0 1 3 CompanyB 1 1 2 0思路是
2
1160pagecount可能会变化，所以输出的列数应该反映出这一点，每个action/pagecount对应一个列，然后统计每个company_name的命中次数。我不确定这是否被称为数据透视表，但有人提出了这个建议 
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我的解决方案是使用T-SQL而没有任何数据透视：
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