Laravel规范化DB中的关系。
所以我的工作表包含工作。和包含类别的类别表。
工作可以有多个类别。
是否有一种平衡关系正常化的方式?
Schema::create('jobs', function($table)
{
$table->increments('id');
$table->integer('user_id')->unsigned();
$table->string('slug');
$table->string('title');
$table->string('excerpt')->nullable();
$table->text('content');
$table->integer('delivery');
$table->integer('price');
$table->unique(array('user_id', 'slug'));
$table->timestamps();
});
Schema::create('categories', function(Blueprint $table)
{
// These columns are needed for Baum's Nested Set implementation to work.
// Column names may be changed, but they *must* all exist and be modified
// in the model.
// Take a look at the model scaffold comments for details.
// We add indexes on parent_id, lft, rgt columns by default.
$table->increments('id');
$table->integer('parent_id')->nullable()->index();
$table->integer('lft')->nullable()->index();
$table->integer('rgt')->nullable()->index();
$table->integer('depth')->nullable();
// Add additional columns here (f.ex: name, slug, path, etc.)
$table->string('name')->unique();
$table->string('slug')->unique();
$table->string('description')->nullable();
});
我的第一直觉是创建一个包含关系的中间表:
Schema::create('jobs_categories', function($table)
{
$table->increments('id');
$table->integer('job_id')->unsigned();
$table->integer('category_id')->unsigned();
$table->unique(array('job_id', 'category_id'));
});
但我不确定如何处理,如果我想获得所有$工作的类别,我该怎么办?
如果我想获得$ job类别该怎么办?
是hasOne,还有更适合这个吗?
答案 0 :(得分:4)
您所描述的是多对多关系。是的,需要像jobs_categories
这样的数据透视表。以下是Laravels命名约定和利用关系后如何做到这一点:
jobs_categories
很好但是Laravel喜欢category_job
(单数和字母顺序)(这样你就不必在你的关系中指定表名)
Schema::create('category_job', function($table){
$table->increments('id');
$table->integer('job_id')->unsigned();
$table->integer('category_id')->unsigned();
$table->unique(array('job_id', 'category_id'));
// foreign key constraints are optional (but pretty useful, especially with cascade delete
$table->foreign('job_id')->references('id')->on('jobs')->onDelete('cascade');
$table->foreign('category_id')->references('id')->on('categories')->onDelete('cascade');
});
public function categories(){
return $this->belongsToMany('Category');
}
public function jobs(){
return $this->belongsToMany('Job');
}
分类为热切加载的作业
$jobs = Job::with('categories')->get();
访问作业的类别
$job = Job::find(1);
$categories = $job->categories;
Visit the Laravel docs for more information on Eloquent relationships