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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)

? 1 2 3 4 5 6 7 8 9 10 11 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)

? 1 2 3 4 5 6 7 8 9 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

? 1 2 3 4 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

? 1 2 3 4 select  name,'yuwen'  as   subjects,yuwen  as  score  from  user_score2  union  all select  name,'shuxue'  as   subjects,shuxue  as  score  from  user_score2 union  all select  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