如何使用 symfony2 学说查询构建器选择不同的查询? [英] How to select distinct query using symfony2 doctrine query builder?

问题描述

我有这个 symfony 代码，它检索与我的项目中的博客部分相关的所有类别:

I have this symfony code where it retrieves all the categories related to a blog section on my project:

$category = $catrep->createQueryBuilder('cc')
    ->Where('cc.contenttype = :type')
    ->setParameter('type', 'blogarticle')
    ->getQuery();

$categories = $category->getResult();

这有效，但查询包含重复项:

This works, but the query includes duplicates:

Test Content
Business
Test Content

我想在查询中使用 DISTINCT 命令.我见过的唯一示例要求我编写原始 SQL.我想尽可能避免这种情况，因为我试图保持所有代码相同，以便它们都使用 Symfony2/Doctrine 提供的 QueryBuilder 功能.

I want to use the DISTINCT command in my query. The only examples I have seen require me to write raw SQL. I want to avoid this as much as possible as I am trying to keep all of my code the same so they all use the QueryBuilder feature supplied by Symfony2/Doctrine.

我尝试将 distinct() 添加到我的查询中，如下所示:

I tried adding distinct() to my query like this:

$category = $catrep->createQueryBuilder('cc')
    ->Where('cc.contenttype = :type')
    ->setParameter('type', 'blogarticle')
    ->distinct('cc.categoryid')
    ->getQuery();

$categories = $category->getResult();

但它导致以下错误:

致命错误:调用未定义的方法 DoctrineORMQueryBuilder::distinct()

Fatal error: Call to undefined method DoctrineORMQueryBuilder::distinct()

我如何告诉 symfony 选择不同的?

How do I tell symfony to select distinct?

推荐答案

你可以写

select DISTINCT f from t;

作为

select f from t group by f;

问题是，我目前刚刚进入 Doctrine，所以我不能给你一个真正的答案.但你可以如上所示，用 group by 并将其转换为 学说.如果你想添加进一步的过滤，那么在 group by 之后使用 HAVING.

thing is, I am just currently myself getting into Doctrine, so I cannot give you a real answer. but you could as shown above, simulate a distinct with group by and transform that into Doctrine. if you want add further filtering then use HAVING after group by.

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