如何消除SQL中的重复计算? [英] How to eliminate duplicate calculation in SQL?

问题描述

我有一个可以简化为的 SQL:

I have a SQL that can be simplified to:

SELECT * 
  FROM table 
 WHERE LOCATE( column, :keyword ) > 0 
ORDER BY LOCATE( column, :keyword )

您可以看到LOCATE( column, :keyword )"的重复项.有没有办法只计算一次?

You can see there is a duplicate of "LOCATE( column, :keyword )". Is there a way to calculate it only once ?

推荐答案

HAVING 在 MySQL 中使用别名:

HAVING works with aliases in MySQL:

SELECT *, LOCATE( column, :keyword ) AS somelabel 
FROM table 
HAVING somelabel > 0 
ORDER BY somelabel

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