教义2，左加入时计数 [英] Doctrine 2, count when left join

问题描述

我有这个:

->select('COUNT(x)')->setMaxResults(null)->setFirstResult(0)->getQuery()->getSingleScalarResult();

只要我没有加入，这就会起作用.如果我已经退出连接，它还将计算重复的左列.如何预防呢?

this works as long as I dont have join. If I have left join, it will also count the duplicated left-columns. How to prevent that?

推荐答案

您可以通过分组来实现:

You can do that by grouping:

$qb->select('COUNT(x)')
   ->leftJoin('x.another_table', 'a')
   ->groupBy('x.id')
   ->setMaxResults(null)
   ->setFirstResult(0)
   ->getQuery()
   ->getSingleScalarResult();

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