Mysql 如何从表中选择数据以转置或交叉表的方式获得输出？

我有一个表reportdata，其中包含以下值：

 reportdata       memberCount     monthname     year
Assigned user        588           February     2017
Assigned user        2             January      2017
Assigned user        22            May          2017
FHD                  571           February     2017
FHD                  15            May          2017
ICM                  1             May          2017
sortingCompleted     1             February     2017
sortingCompleted     2             May          2017

我希望输出像：

   reportdata           January   February      May
    Assigned user           2       588          22
       FHD                  0       571          15
       ICM                  0        0            1
   sortingCompleted         0        1            2

我尝试了以下问题：

select d.reportdata,
CASE WHEN d.monthname='January' THEN d.MemberCount END AS January,
CASE WHEN d.monthname='February' THEN d.MemberCount END AS February,  
CASE WHEN d.monthname='May' THEN d.MemberCount END AS May from
(
select reportdata, memberCount,monthname
from cme_report where year='2017'
) as d

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请建议获得预期输出的方法。感谢是预付款。

您可以尝试以下方法：

SELECT
    reportdata,
    SUM(CASE WHEN (monthname = 'January') THEN memberCount ELSE 0 END) AS 'January',
    SUM(CASE WHEN (monthname = 'February') THEN memberCount ELSE 0 END) AS 'February',
    SUM(CASE WHEN (monthname = 'May') THEN memberCount ELSE 0 END) AS 'May', 
FROM reportdata
WHERE year = '2017'
GROUP BY reportdata

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非常感谢@Sebastian Brosch，这一切都很好。。。。。谢谢。。。。