這篇文章通過sql示例代碼給大家介紹了mysql數據庫如何實現行列轉換，下面話不多說，直接來看示例代碼吧。
原表：
表名 :user----------------------------------------name | course | grade----------------------------------------zhangsan | Java | 70----------------------------------------zhangsan | C++ | 80----------------------------------------lisi | java | 90----------------------------------------lisi | C# | 60----------------------------------------
用一條 SQL 語句得到如下形式：
----------------------------------------name | java | C++ | C#----------------------------------------zhangsan | 70 | 80 | null----------------------------------------lisi | 90 | null | 60----------------------------------------
方案一
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
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
總結
以上就是這篇文章的全部內容了，希望本文的內容對大家的學習或者工作能有一定的幫助，如果有疑問大家可以留言交流。
新聞熱點
疑難解答
