基于相关表数据的计数的订单数据 [英] Order data based on count of related table data

问题描述

我有两个比较表，如下所示：

I have Two diff tables as given below:

用户和帖子

根据帖子数量表排序

关系定义为：

User Model:

public $hasMany = array('Post');

Post Model

Public $belongsTo = array('User');

推荐答案

counterCache - / strong>

counterCache - Cache your count()

此函数可帮助您缓存相关数据的计数。不是通过 find（'count'）手动计数记录，模型本身会跟踪对相关 $ hasMany 模型的任何添加/删除，并增加/减少专用整数字段

This function helps you cache the count of related data. Instead of counting the records manually via find('count'), the model itself tracks any addition/deleting towards the associated $hasMany model and increases/decreases a dedicated integer field within the parent model table.

字段的名称由单个模型名称后跟下划线和单词count组成：

The name of the field consists of the singular model name followed by a underscore and the word "count":

my_model_count

具有名为 ImageComment 的模型和名为图像的模型，则可以向图像表中添加一个新的INT字段，并将其命名为 image_comment_count 。

Let’s say you have a model called ImageComment and a model called Image, you would add a new INT-field to the image table and name it image_comment_count.

一旦你添加了计数器字段，你就可以去了。通过添加 counterCache 键并将值设置为 true ，在关联中启用计数器缓存：

Once you have added the counter field you are good to go. Activate counter-cache in your association by adding a counterCache key and set the value to true:

<?php
class Image extends AppModel {
    public $belongsTo = array(
        'ImageAlbum' => array('counterCache' => true)
    );
}

从现在开始，每次添加或删除 / strong>关联到 ImageAlbum ， image_count 中的数字会自动调整。

From now on, every time you add or remove a Image associated to ImageAlbum, the number within image_count is adjusted automatically.

> counterScope 。它允许你指定一个简单的条件，告诉模型什么时候更新（或者什么时候不会，取决于你如何看待它）计数器值。

You can also specify counterScope. It allows you to specify a simple condition which tells the model when to update (or when not to, depending on how you look at it) the counter value.

使用我们的图像模型示例中，我们可以像这样指定：

Using our Image model example, we can specify it like so:

<?php
class Image extends AppModel {
    public $belongsTo = array(
        'ImageAlbum' => array(
            'counterCache' => true,
            'counterScope' => array('Image.active' => 1) // only count if "Image" is active = 1
    ));
}

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