mysql - 我的SQL查询找到＃状态

我有一个表，其中包含列名“课程”和“状态”，如下所示

Course    Status
---------------------------
Math      Complete
Math      Complete
Math      Complete
Science   Incomplete
Science   Complete
Science   Complete

我想对谁给出以下结果的MySQL查询

Course    % Status_complete
--------------------------
Math        100%
Science     33.3%

最佳答案

SELECT  Course,
        SUM(Status = 'Complete') / COUNT(*) * 1.0 AS STATUS_COMPLETE
FROM    TableName
GROUP   BY Course

SQLFiddle Demo
SQLFiddle Demo (with % symbol and ROUND())

关于mysql - 我的SQL查询找到＃状态，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/16687760/