How to change the vertical to horizontal arrangement in mysql
This article will introduce how to use sql statements to change table data from vertical display to horizontal display.
Recommended courses: MySQL Tutorial.
In mysql, the case when statement can be used to query vertical to horizontal. The specific steps are as follows:
The first step is to create a data table , I have created it here, and the following is a display data chart.
The second step is to display the total score of each class vertically, using the following statement:
select class,sum(score) from student group by class;
Query results:
The third step is to display the results horizontally, use the case when statement, the statement is as follows:
select sum(case when class='一年一班' then score else 0 end) 一年一班成绩, sum(case when class='一年二班' then score else 0 end) 一年二班成绩, sum(case when class='一年三班' then score else 0 end) 一年三班成绩 from student;
Query results:
The above is the detailed content of How to change the vertical to horizontal arrangement in mysql. For more information, please follow other related articles on the PHP Chinese website!

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