如何从与枢轴相关的行--Laravel获取一个Builder对象 [英] How to get a Builder object from rows related to pivot - Laravel

问题描述

我正在尝试获取一个用户拥有的所有书籍：但是我无法做到这一点。

I'm trying to get all the "books" that one user have: but I can't do it how I need.

我使用以下代码：

/*Gets all books from the user whose id is 1*/     
$books= User::find(1)->books();

返回给我一个集合但我需要一个 Builder 对象，当我使用select方法时，我需要。

That return to me an Collection object; but I need a Builder object, as I get when I use the "select" method.

/* This code return me a "Builder" object */
Books::select(array('id', 'name', 'type'));

我需要 Builder 而不是 Collection 因为我在我的项目中使用Bllim / Datatables，而这个包只是接受一个 Builder 对象...

I need the Builder instead of Collection because I using Bllim/Datatables on my project and this package just accept a Builder object...

如果我发送一个集合，它会抛出下一个错误（500 - 内部服务器错误）：

If I send it a Collection its throw me the next error (500 - Internal Server Error):

{
  "error":
   {
           "type":"ErrorException",
           "message":"Undefined property: Illuminate\\Database\\Eloquent\\Builder::$columns",
           "file":"\/var\/www\/proyect\/myproyect\/vendor\/bllim\/datatables\/src\/Bllim\/Datatables\/Datatables.php",
           "line":256
   }
}

有人知道解决方案吗？

Anybody knows the solution?

编辑：

当我使用getQuery（）以下错误：

When I use the getQuery() method twice I get the following error:

{"error":{"type":"ErrorException","message":"array_values() expects parameter 1 to be array, null given","file":"\/var\/www\/proyect\/myproyect\/vendor\/bllim\/datatables\/src\/Bllim\/Datatables\/Datatables.php","line":550}}

是罕见的，因为当我使用选择方法Datatables工作完美...

Is rare, because when I used the "select" method Datatables worked perfectly...

此代码工作原理：

Books::select(array('id', 'name', 'type'));

但是你告诉我的代码不起作用：

But the code you told me doesn't work:

$user = User::find(1);
$user->books()->getQuery()->getQuery();

推荐答案

使用方法调用 ）：

$user = User::find(1);

$user->books(); // relation object
$user->books; // dynamic property

首先 books（）返回一个关系对象，您可以链接 Eloquenr\Builder 或查询构建器方法。

First books() returns a relation object, that you can chain Eloquenr\Builder or Query Builder methods on.

第二个书籍是一个动态属性 - 查询自动执行，其结果存储在$ code $ $ - >关系['books'] 并返回。

Second books is a dynamic property - the query is automatically executed and its result is stored in the $user->relations['books'] and returned.

编辑

根据评论 - 您需要的是基础 Query\Builder 对象，如果您要访问列属性，所以你需要 getQuery 两次：

As per comment - what you need is base Query\Builder object if you want to access columns property, so you need getQuery twice:

$user->books()
   ->getQuery() // get underlying Eloquent\Builder
   ->getQuery() // get underlying Query\Builder
   ->columns    // public property on the above

这篇关于如何从与枢轴相关的行--Laravel获取一个Builder对象的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！