Relationship between Eloquent in Laravel 5 framework learning, laraveleloquent

Relationship between Eloquent in Laravel 5 framework learning, laraveleloquent

A user may have multiple articles. One article is written by a user. This is the relationship. The same article may contain multiple tags, and one TAG may be associated with multiple articles.

In the project, we already have User. php, that is, the User model. It is quite simple to check. We want to get all the articles in the form of $ user-> articles (). Let's modify the user model:

  public function articles() {    return $this->hasMany('App\Article');  }

But we only completed one end of the link. Let's deal with the other end. The expected format is $ article-> user (). Let's modify the article model.

  public function user() {    return $this->belongsTo('App\User');  }

In our database, the document model does not have a user's foreign key. We need to set and modify create_article_table.php.

Schema: create ('articles', function (Blueprint $ table) {$ table-> increments ('id '); // specify the foreign key column $ table-> integer ('user _ id')-> unsigned (); $ table-> string ('title '); $ table-> text ('body'); $ table-> timestamp ('hhed _ at'); $ table-> timestamps (); // generate a foreign key $ table-> foreign ('user _ id')-> references ('id')-> on ('users ') -> onDelete ('cascade ');});

Because we are only in the development stage and haven't been online yet, we can directly modify the database migration file, roll back and migrate it. But if it is online, we should create a new migration.

Php artisan migrate: refresh # Rolled back: rollback back: failed to rollback. Migrated: 2014_10_12_000000_create_users_tableMigrated: pushed

Now let's use tinker to create a user.

Php artisan tinkerPsy Shell v0.4.1 (PHP 5.4.16-cli) by Justin Hileman # The following is the execution process >>>$ user = new App \ User; ==>< App \ User # commandid 7f1ad61a000000006497cc4f >{}>>> $ user-> name = 'zhang jinglin '; => "zhang jinglin" >>>$ user-> email = 'zjl @ example.com '; => "zjl@example.com" >>>$ user-> password = bcrypt ('pass'); => "$ 2y $10 $ Nbl2b9wqd. rxqkesd3prsooiyfafihb%71bufwdfs3guv21slex2 ">>>$ user-> save () ;=> true >>> App \ User: first ()-> toArray (); => ["id" => "1", "name" => "zhang jinglin", "email" => "zjl@example.com ", "created_at" => "03:24:55", "updated_at" => "03:24:55"]>

Now we need to associate the newly published article with the user. For the moment, we need to modify form_partial.blade.php to hide a user ID, but for the moment:

Copy codeThe Code is as follows:
{-- Temporary processing --}}
{!! Form: hidden ('user _ id', 1 )!!}

At the same time, we need to modify the $ fillabel attribute of the model for our Mass Assisment.

Protected $ fillable = ['title', 'body', 'hhed _ at', 'user _ id' // temporary settings];

OK. add an article. We can use tinker to check the problem.

Php artisan tinkerPsy Shell v0.4.1 (PHP 5.4.16-cli) by Justin Hileman >>> App \ Article: first ()-> toArray (); => ["id" => "1", "user_id" => "1", "title" => "User 1 Article ", "body" => "User 1 Body", "published_at" => "08:00:00", "created_at" => "04:17:58 ", "updated_at" => "04:17:58", "excerpt" => null] # Get a user >>>$ User = App \ user: first (); => <App \ User # commandid 51cbb9d70 201700073e11a3e> {id: "1", name: "zhang jinglin", email: "zjl@example.com", created_at: "03:24:55", updated_at: "03:24:55" }# get user articles >>>$ user-> articles ()-> toArray (); badMethodCallException with message 'Call to undefined method Illuminate \ Database \ Query \ Builder: toArray () '>>>$ user-> articles-> toArray (); => [["id" => "1", "user_id" => "1", "title" => "User 1 Article", "body" => "User 1 Body", "published_at" => "08:00:00", "created_at" => "04:17:58", "updated_at" => "04:17:58 ", "excerpt" => null] # Why use $ user-> articles instead of # user-> articles ()? # In fact, $ user-> articles () returns a link. If you want to use articles (), you need to use >>>$ user-> articles ()-> get () -> toArray (); => [["id" => "1", "user_id" => "1", "title" => "User 1 Article ", "body" => "User 1 Body", "published_at" => "08:00:00", "created_at" => "04:17:58 ", "updated_at" => "04:17:58", "excerpt" => null] # You can only use articles () for the next step, for example, the following query $ user-> articles ()-> where ('title', 'user 1 article')-> get (); # You can also get user >>$ article = App \ article: first () ;=> <App \ Article # commandid 51cbb9d60000000073e11a3e >{ id: "1 ", user_id: "1", title: "User 1 Article", body: "User 1 Body", published_at: "08:00:00", created_at: "04:17:58", updated_at: "04:17:58", excerpt: null }>>>$ article-> user ;=>< App \ User # commandid 51cbb92d=73e11a3e >{ id: "1", name: "zhang jinglin", email: "zjl@example.com", created_at: "03:24:55", updated_at: "03:24:55" >>>

The above is all the content of this article. I hope you will like it.