laravel-mongodb：如何将外键添加到两个现有集合？

Question

我使用laravel-mongodb（https://github.com/jenssegers/laravel-mongodb）MongoDB中操纵数据，

我在MongoDB的两个集合，它们是books和categories。

后来我将它们导入到mysql中，所以我想先将它们与外键相关联。

让他们从MongoDB的：

public function getBooksAndCategories() 
{ 
    $books = DB::connection('mongodb')->collection('books')->get(); 
    $categories = DB::connection('mongodb')->collection('categories')->get(); 
} 

，就像这样：

$books = collect([ 
     ['_id' => 'xxx','name' => 'history book 1', 'category' => 'history'], 
     ['_id' => 'xxx','name' => 'history book 2', 'category' => 'history'], 
     ['_id' => 'xxx','name' => 'science book 1', 'category' => 'science'], 
     ['_id' => 'xxx','name' => 'science book 2', 'category' => 'science'], 
     ['_id' => 'xxx','name' => 'sociology book 1', 'category' => 'sociology'], 
     ['_id' => 'xxx','name' => 'sociology book 2', 'category' => 'sociology'], 
     ['_id' => 'xxx','name' => 'economics book 1', 'category' => 'economics'], 
    ]); 




    $categories = collect([ 
     ['_id' => 'xxx','category' => 'history'], 
     ['_id' => 'xxx','category' => 'science'], 
     ['_id' => 'xxx','category' => 'sociology'], 
     ['_id' => 'xxx','category' => 'economics'], 
    ]); 

第一，我需要添加一个id到$categories，结果是这样的：

$newCategories = collect([ 
     ['_id' => 'xxx','category' => 'history','id' => 1], 
     ['_id' => 'xxx','category' => 'science','id' => 2], 
     ['_id' => 'xxx','category' => 'sociology','id' => 3], 
     ['_id' => 'xxx','category' => 'economics','id' => 4], 
    ]); 

秒，我需要添加一个外键到集合$books，结果是这样的：

$newBooks = collect([ 
     ['_id' => 'xxx','name' => 'history book 1', 'category' => 'history','category_id' => 1], 
     ['_id' => 'xxx','name' => 'history book 2', 'category' => 'history','category_id' => 1], 
     ['_id' => 'xxx','name' => 'science book 1', 'category' => 'science','category_id' => 2], 
     ['_id' => 'xxx','name' => 'science book 2', 'category' => 'science','category_id' => 2], 
     ['_id' => 'xxx','name' => 'sociology book 1', 'category' => 'sociology','category_id' => 3], 
     ['_id' => 'xxx','name' => 'sociology book 2', 'category' => 'sociology','category_id' => 3], 
     ['_id' => 'xxx','name' => 'economics book 1', 'category' => 'economics','category_id' => 4], 
    ]); 

我不知道如何与laravel-mongodb做到这一点，有什么建议？

Answer 1

尝试这样的：

$last_new_id = 1; 

foreach($categories as $category){ 
    $category->id = $last_new_id ; 
    $last_new_id++; 
} 

foreach($books as $book){ 
    $book->category_id = $categories->where('category',$book->category)->first()->id 
}