mysql - 计算

Question

我想返回简单计算的结果，但我不确定如何执行此操作。我的表格如下:

SELECT
    COUNT(fb.engineer_id) AS `total_feedback`, 
    SUM(fb.rating) AS `total_rating`, fb.engineer_id 
FROM 
    `feedback` AS fb 

现在，当我返回结果时，我使用 PHP 进行计算，但现在我想按结果对结果进行排序(此查询嵌套在一个更大的查询中)。

计算如下:

$p = ((($total_rating*20)*$total_feedback)/10);

这可以在初始查询中完成吗？

Answer 1

你可以做到

SELECT
    COUNT(fb.engineer_id) AS `total_feedback`, 
    SUM(fb.rating) AS `total_rating`, fb.engineer_id 
FROM 
    `feedback` AS fb 
ORDER BY total_rating*20*total_feedback/10

或者如果您希望该列出现在结果中:

SELECT
    COUNT(fb.engineer_id) AS `total_feedback`, 
    SUM(fb.rating) AS `total_rating`, fb.engineer_id 
    total_rating*20*total_feedback/10 AS p
FROM 
    `feedback` AS fb 
ORDER BY p