LIMIT在ActiveDataProvider中不起作用

Question

嗨,大家好我正在使用以下代码,并limit没有工作,但如果我看到的命令比它显示limit在那,但当我将查询传递给ActiveDataProvider它获取所有记录

$data= User::find()->where(['category_id'=> 5])->orderBy(['rand()' => SORT_DESC])->limit(4);

    $command = $data->createCommand();

    $data2 = $command->queryAll();// This works fine and fetch only 4 data 

    $dataProvider = new ActiveDataProvider([
        'query' => $data,

    ]); // But this displays all data without limit

我在这做什么错了???

Answer 1

以下是在准备模型时发生的情况yii\data\ActiveDataProvider:

/**
 * @inheritdoc
 */
protected function prepareModels()
{
    if (!$this->query instanceof QueryInterface) {
        throw new InvalidConfigException('The "query" property must be an instance of a class that implements the QueryInterface e.g. yii\db\Query or its subclasses.');
    }
    $query = clone $this->query;
    if (($pagination = $this->getPagination()) !== false) {
        $pagination->totalCount = $this->getTotalCount();
        $query->limit($pagination->getLimit())->offset($pagination->getOffset());
    }
    if (($sort = $this->getSort()) !== false) {
        $query->addOrderBy($sort->getOrders());
    }

    return $query->all($this->db);
}

我们对这部分感兴趣:

if (($pagination = $this->getPagination()) !== false) {
    $pagination->totalCount = $this->getTotalCount();
    $query->limit($pagination->getLimit())->offset($pagination->getOffset());
}

因此,您可以看到分页是否不是false,自动管理限制.

您可以设置分页false,然后手动设置限制将起作用:

$dataProvider = new ActiveDataProvider([
    'query' => $query,
    'pagination' => false,
]); 

Answer 2

您可以在ActiveDataProvider中使用Limit 并保持分页，如下所示：

$dataProvider = new ActiveDataProvider([
        'query' => $query,
         'pagination' => [
             'pageSize' => 50, 
         ],
    ]);
$dataProvider->setTotalCount(1000);

这将使$this->getTotalCount() = 1000并保持分页。转到此处和此处以获取更多参考。