Doctrine 2 使用关联映射进行分页 [英] Doctrine 2 Pagination with Association Mapping

问题描述

我想知道如何对从 Doctrine 2 中的实体关联映射获得的结果进行分页?例如

class Customer {
  /**
   * @OneToMany(targetEntity="Order")
   */
  private $orders;
}

可以这样使用:

$customer->getOrders();

这将返回 Order 对象的集合.

which will return a collection of Order objects.

问题是当有大量订单对象时.

The problem is when there are a large number of order objects.

我们可以在构建自定义查询时使用 DoctrineORMToolsPaginationPaginator，但是在使用关联映射时我看不到任何方法可以挂钩查询生成.

We can use DoctrineORMToolsPaginationPaginator when building custom queries, however I do not see any way to hook into query generation when utilising association mapping.

class Paginator {
  /** 
   * @param Query|QueryBuilder $query A Doctrine ORM query or query builder. 
   */
  function __construct(
    //....

推荐答案

如果使用EXTRA_LAZY fetch 模式，Doctrine 将不会在水合集合时检索所有对象.它只会在您对集合使用 slice() 方法时检索所需的子集.

If you use the EXTRA_LAZY fetch mode, Doctrine will not retrieve all objects when hydrating the collection. It will only retrieve the subset needed when you use the slice() method on the collection.

class Customer {
    /**
     * @OneToMany(targetEntity="Order", fetch="EXTRA_LAZY")
     */
    private $orders;
}

$cust = new Customer;
$orders = $cust->getOrders()->slice(100, 50);

您需要验证它如何与分页交互.

You would need to verify how this interacts with the pagination.

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