尝试从Symfony2中的数据库获取列的总和时出错

Question

我正在尝试在数据库列中获取多个值的总和：

                $goalsScored = $em->createQueryBuilder()
                ->select('sum(homeGoals)')
                ->from('LoginLoginBundle:Matchgame', 'mg')
                ->where("mg.homeTeam LIKE '" . $oneTeam->getTeamid()."'")
                ->getQuery()
                ->getSingleScalarResult();

我收到以下错误：

[Semantical Error] line 0, col 11 near 'homeGoals) FROM': Error: 'homeGoals' is not defined. 

homeGoals在我的数据库中定义，为什么我会收到此错误？是因为某些值为空吗？

Answer 1

您的选择中缺少表别名：

    $goalsScored = $em->createQueryBuilder()
    ->select('sum(mg.homeGoals)')
    ->from('LoginLoginBundle:Matchgame', 'mg')
    ->where("mg.homeTeam LIKE '" . $oneTeam->getTeamid()."'")
    ->getQuery()
    ->getSingleScalarResult();