本文实例讲述了mysql横纵表相互转化操作实现方法。分享给大家供大家参考，具体如下：
先创建一个成绩表（纵表）
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create table user_score( name varchar(20), subjects varchar(20), score int);insert into user_score(name,subjects,score) values('张三','语文',60);insert into user_score(name,subjects,score) values('张三','数学',70);insert into user_score(name,subjects,score) values('张三','英语',80);insert into user_score(name,subjects,score) values('李四','语文',90);insert into user_score(name,subjects,score) values('李四','数学',100); |
再创建一个成绩表（横表）
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create table user_score2( name varchar(20), yuwen int, shuxue int, yingyu int);insert into user_score2(name,yuwen,shuxue,yingyu) values('张三',60,70,80);insert into user_score2(name,yuwen,shuxue,yingyu) values('李四',90,100,0); |
纵表转横表
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select name,sum(case subjects when '语文' then score else 0 end) as '语文',sum(case subjects when '数学' then score else 0 end) as '数学', sum(case subjects when '英语' then score else 0 end) as '英语'from user_score group by name; |
纵表转横表
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select name,'yuwen' as subjects,yuwen as score from user_score2 union allselect name,'shuxue' as subjects,shuxue as score from user_score2 union allselect name,'yingyu' as subjects,yingyu as score from user_score2 order by name,subjects desc; |
希望本文所述对大家MySQL数据库计有所帮助。
原文链接：https://blog.csdn.net/huangyuxin_/article/details/79678719
