mysql實現行轉列的方法:1、用cross join的方式實現,代碼為【cross join(select sum(a.kills) ‘豬八戒】;2、用case語句的方式實現,代碼為【case when user_name=’孫悟空’】。
本教程操作環境:windows7系統、mysql8.0.22版,該方法適用于所有品牌電腦。
mysql實現行轉列的方法:
1、用cross join的方式實現
select?*?from? (select?sum(a.kills)?'孫悟空'? ??from?kills1?as?a? ??LEFT?JOIN?tssrz?as?b? ????on?a.user_id?=?b.id? ?WHERE?b.user_name?=?'孫悟空'? ?GROUP?BY?b.user_name)?e ?cross?join? ?(select?sum(a.kills)?'豬八戒'? ??from?kills1?as?a? ??LEFT?JOIN?tssrz?as?b? ????on?a.user_id?=?b.id? ?WHERE?b.user_name?=?'豬八戒'? ?GROUP?BY?b.user_name)?f
2、用case語句的方式實現
SELECT?sum(case?when?user_name='孫悟空'?then?kills?end)?as?'孫悟空', ??sum(case?when?user_name='豬八戒'?then?kills?END)?as?'豬八戒', ??sum(case?when?user_name='沙和尚'?then?kills?END)?as?'沙和尚' ???from?tssrz?as?a ???join?kills1?as?b ?????on?a.id?=?b.user_id
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