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Eloquent Relationships 357
13 $album->artist()->associate($artist);
14 $album->save();
15
16 return View::make('hello');
17 });
Wait, what’s this new line?
1 $album->artist()->associate($artist);
Let’s break the method chain down. Here’s the first method.
1 $album->artist();
Do you remember that method? That’s the relationship method that we created on the Album object.
So what exactly does it return? The method returns an instance of the Eloquent query builder, just
like the the one that we used in a previous chapter.
However, this query builder instance will have some constraints placed on it for us. The current set
of results represented by the query builder will be the related Artists (in this case, a collection of
one) to our Album.
It’s the same as the following.
1 Artist::where('album_id', '=', __OUR__CURRENT__ALBUM__);
That’s handy right? We could chain on more queries if we wanted to. For example:
1 $album->artist()->where('genre', '=', 'rock')->take(2);
Be sure to remember that the query builder required a trigger method at the end of the join to return
a result collection. Like this:
1 $album->artist()->where('genre', '=', 'rock')->take(2)->get();
This also means that we can retrieve a full collection of related artists by performing the following.
1 $album->artist()->get();
Or, a single instance using the first() trigger method.