这篇文章通过sql示例代码给大家介绍了mysql数据库如何实现行列转换，下面话不多说，直接来看示例代码吧。
原表：
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表名 :user----------------------------------------name | course | grade----------------------------------------zhangsan | Java | 70----------------------------------------zhangsan | C++ | 80----------------------------------------lisi | java | 90----------------------------------------lisi | C# | 60---------------------------------------- |
用一条 SQL 语句得到如下形式：
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----------------------------------------name | java | C++ | C#----------------------------------------zhangsan | 70 | 80 | null----------------------------------------lisi | 90 | null | 60---------------------------------------- |
方案一
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select name,sum(case when course='java' then grade end) as java,sum(case when course='C++' then grade end) as C++,sum(case when course='C#' then grade end) as C#from test group by name |
方案二
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select distinct c.`name` AS name,(select grade from test where name = c.`name` and course = 'java' )as java,(select grade from test where name = c.`name` and course = 'C++' )as C++,(select grade from test where name = c.`name` and course = 'C#' )as C#from test c |
总结
以上就是这篇文章的全部内容了，希望本文的内容对大家的学习或者工作能有一定的帮助，如果有疑问大家可以留言交流。
