如何通过DQL中的计算值进行排序 [英] How to order by a computed value in DQL

问题描述

我正在尝试通过查询是否与属性上的原始实体匹配来排序查询结果。我可以在mySQL中轻松地执行以下查询：

I'm trying to order the results of my query by whether or not they match my original entity on a property. I could do this easily in mySQL with the following query:

SELECT * FROM table
ORDER BY prop = 'value' DESC;

但是，在Doctrine中，当我尝试以下操作：

However, in Doctrine, when I attempt the following:

// $qb is an instance of query builder
$qb->select('e')
   ->from('Entity', 'e')
   ->orderBy('e.prop = :value', 'DESC')
   ->setParameter('value', 'value');
// grab values

我得到一个Doctrine语法错误，string of string。我研究创建一个自定义函数，但这似乎是过度的。我是Doctrine的新手，有没有更好的方法呢？

I get a Doctrine syntax error, 'end of string'. I looked into creating a custom function, but that seems like overkill. I'm fairly new to Doctrine, is there a better way to do this?

推荐答案

自从Doctrine ORM 2.2以来，你可以使用 HIDDEN 关键字，并选择其他字段，在本例中为CASE 表达式：

Since Doctrine ORM 2.2, you can use the HIDDEN keyword and select additional fields, in this case with a CASE expression:

SELECT
    e,
    CASE WHEN e.prop = :value THEN 1 ELSE 0 END AS HIDDEN sortCondition
FROM
    Entity e
ORDER BY
    sortCondition DESC

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