CakePHP 3包含​​选择字段

Question

我有以下数据库表:项目,用户,组,itemImages.(项目,组)和(用户,组)之间存在多对多关系,(项目,项目图像)之间存在一对多关系.所有相应的外键都已在CakePHP中设置为关联.

如何使用contains()构造一个查询,该查询选择所有项目及其主图像,这些项目位于已被指定为具有特定ID的用户的主要组的组中？

为了更清楚,这是一个简单的SQL查询的样子:

SELECT items.id AS itemId, items.name, itemImages.url AS itemUrl
FROM items
INNER JOIN groups_items ON groups_items.item_id = items.id
INNER JOIN groups ON groups_images.group_id = groups.id
INNER JOIN groups_users ON groups_users.group_id = groups.id
INNER JOIN users ON groups_users.user_id = users.id
INNER JOIN itemImages ON itemImages.item_id = items.id
WHERE groups_users.isMainGroup = 1
    AND users.id = :userId
    AND itemImages.isMainImage = 1

CakePHP代码我现在有:

$items = $this->Items->find()
            ->hydrate(false)
            ->contain([
                'Groups.Users' => function($q) use ($userId){
                    return $q->where(['isMainGroup' => 1, 'Users.id' => $userId]);
                },
                'ItemImages' => function($q){
                    return $q->where(['isMainImage' => 1]);
                },
            ]);
            //->select(['itemId' => 'Items.id', 'Items.name', 'itemUrl' => 'itemImages.url']);

Answer 1

matching()方法可以帮助解决这个问题

$items = $this->Items->find()
        ->hydrate(false)
        ->select(['Items.id', 'Items.name', 'itemImages.url'])
        ->distinct(['Items.id'])
        ->matching('Groups.Users', function ($q) use ($userId) {
            return $q->where(['Groups.isMainGroup' => 1, 'Users.id' => $userId]);
        })
        ->matching('ItemImages', function ($q) {
            return $q->where(['ItemImages.isMainImage' => 1]);
        })
        ->contain([
            'ItemImages' => function ($q) {
                return $q->autoFields(false)
                         ->select(['id','url'])
                         ->where(['ItemImages.isMainImage' => 1]);
            }
        ]);

我认为,在这种情况下,可以省略最后一个contains语句,因为所需的结果已经在_matchingData属性中.

关于distict ()的注意事项:

由于此函数将创建INNER JOIN,您可能需要考虑在查找查询上调用distinct,因为如果您的条件不过滤它们,您可能会获得重复的行

http://book.cakephp.org/3.0/en/orm/retrieving-data-and-resultsets.html#filtering-by-associated-data