学说额外的懒惰负载不能像预期的那样工作 [英] doctrine extra lazy load doesn't work as expected with count

问题描述

我有一个实体 Shop 和相关实体 ShopProduct ，具有以下关系：

  / ** 
 * @ ORM\OneToMany（targetEntity =ShopProduct，mappedBy =shopid ，fetch =EXTRA_LAZY）
 * / 
 private $ products; 
  

在twig模板中，我想访问 $ c>产品，所以我访问

  {{entity.getProducts（）。count}} 
  

但是，当使用symfony2分析器查看查询的数量和内容时，我看到一个完整的选择是发出的，而不是 COUNT 我会期望（基于文档）。

发送每个 Shop 的内存使用量为250Mb +，页面加载时间为30+秒，这是不需要的。

添加 fetch =EXTRA_LAZY我已经清除了学说缓存。

我是否忽略某些东西，使用错误的方法或误解文档？ / p>

  doctrine / annotations v1.1 
 doctr ine / cache v1.0 
原则/集合v1.1 
原则/常见2.4.0-RC1 
原则/数据夹具dev-master eef10f6 
 doctrine / dbal 2.3。 3 
 doctrine / doctrine-bundle v1.2.0-beta1 
 doctrine / doctrine-fixtures-bundle dev-master 275540d 
 doctrine / doctrine-migrations-bundle dev-master 99c0192 
 doctrine / inflector v1.0 
 doctrine / lexer v1.0 
 doctrine / migrations dev-master e1f6efc 
 doctrine / orm 2.3.3 
  

解决方案

刚刚遇到同样的问题，解决方案非常简单：

{{value.getAlerts.count（）}}

而不是

{{value.getAlerts.count}}

Twig必须覆盖Doctrine count（）方法意味着Extra Laz y加载一个变体，它是自己的实现，只是愚蠢地获取所有的实体来对它们进行计数。

将所有预期的SELECT *查询转换为COUNT（*）...

I have an entity Shop and a related entity ShopProduct, with the following relation:

/**
 * @ORM\OneToMany(targetEntity="ShopProduct", mappedBy="shopid", fetch="EXTRA_LAZY")
 */
private $products;

In a twig template I want to access the count of products, so I access

{{ entity.getProducts().count }}

But when using the symfony2 profiler to look at number and content of the queries, I see that a full select is issued, instead of the COUNT I would expect (based on the documentation).

Issuing the full select for each of the Shops results in a memory usage of 250Mb+ and a page load time of 30+ seconds, which is undesired.

After adding the fetch="EXTRA_LAZY" I've cleared the doctrine caches.

Am I overlooking something, using the wrong approach or misunderstanding the docs?

[edit]

doctrine/annotations                v1.1
doctrine/cache                      v1.0
doctrine/collections                v1.1
doctrine/common                     2.4.0-RC1
doctrine/data-fixtures              dev-master eef10f6
doctrine/dbal                       2.3.3
doctrine/doctrine-bundle            v1.2.0-beta1
doctrine/doctrine-fixtures-bundle   dev-master 275540d
doctrine/doctrine-migrations-bundle dev-master 99c0192
doctrine/inflector                  v1.0
doctrine/lexer                      v1.0
doctrine/migrations                 dev-master e1f6efc
doctrine/orm                        2.3.3

解决方案

Just encountered the same problem and the solution was very simple:

{{ value.getAlerts.count() }}

instead of

{{ value.getAlerts.count }}

Twig must be overriding the Doctrine count() method meant to "Extra Lazy Load" with a variant of it's own implementation that just dumbly fetches all entities to count them.

That turned all expected SELECT * queries into COUNT(*)...

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