Level 75
laravel API is a great place to search.
May 24, 2020
14
Level 10
Is there a way to see what Laravel is expecting for the magic behind the scenes?
I have two models, Event and Interactive Level. Event belongs to Interactive Level and Interactive Level can have many events. In my migration I have
Schema::create('interactive_levels', function (Blueprint $table)
so in my event model I created
$table->foreignId('interactive_level_id')->nullable();
I assumed this would connect the two in the back end with Laravel's magic but it doesn't work. If I do
dd($event->interactivelevel);
nothing happens. However if I add my own foreign key like so
public function interactivelevel()
{
return $this->belongsTo(InteractiveLevel::class, 'interactive_level_id');
}
it works. Is there a way for me to see what Laravel is looking for as a foreign key?? Sorta like Route:list but for foreign keys.
Level 10
Hi @jlrdw I am at https://laravel.com/api/7.x/Illuminate/Database/Eloquent/Relations/BelongsTo.html but I am not exactly sure how to read this.
Level 75
There should be a reference to the actual GitHub code.
When all is said and done it reduces down to normal PDO SQL.
Level 10
hmmm this is helpful but still a little beyond me.
Level 75
Do a query log and get the outputted query.
Level 10
Thanks!
Level 67
FYI laravel debugbar shows all of your queries run on a page. A great development tool. It's the very first thing I always install right after laravel itself. It shows a great deal more info than just queries, too.
Level 10
I do have debugbar but when I look at it without adding my own foreign key I see...
select * from `interactive_levels` where `interactive_levels`.`id` is null order by `rank` desc limit 1
then when I add the foreign key back
return $this->belongsTo(InteractiveLevel::class, 'interactive_level_id');
and look back at my debug bar I see
select * from `interactive_levels` where `interactive_levels`.`id` = 1 order by `rank` desc limit 1
How do I tell what I am naming incorrectly?
Level 67
I don't understand what you're asking by "naming things correctly." Doesn't the debug bar show the same query as it does when enabling query logging?
I assumed this would connect the two in the back end with Laravel's magic but it doesn't work.
The magic comes in when you manually add the foreign key relationship like you did, which instructs laravel about it. There isn't anything that I'm aware of that will tell you that unless you supply it yourself. If tables are related to each other, there should be a relationship defined.
One thing you can do that will help is to utilize Laravel Eloquent Model Conventions: https://laravel.com/docs/7.x/eloquent#eloquent-model-conventions
You shouldn't need to tell it that interactive_level_id is the foreign key. It can figure that part out if the classnames and everything else follow the naming conventions.
Level 10
Ok! I figured it out. Eloquent determines the default foreign key name by examining the name of the relationship method and suffixing the method name with _id. So when I was naming my relationship
public function interactivelevel()
Laravel was then looking for interactivelevel_id! So all I did was change my relationship to
public function interactive_level()
and it worked!
Level 75
@chrisgrim conventions like:
model is automatically assumed to have a user_id
Is in the chapter on https://laravel.com/docs/7.x/eloquent-relationships.
From your question, it sounded like you wanted the "behind the scenes" php code Taylor uses.
So I am sorry if I answered wrong, or did not understand what you were after.
Level 10
@jlrdw Im sorry I wasn't more clear. Sometimes it is almost as hard to write the question as to understand what is going wrong!!
Level 67
You shouldn't need to tell it that interactive_level_id is the foreign key. It can figure that part out if the classnames and everything else follow the naming conventions.
Ok! I figured it out. Eloquent determines the default foreign key name by examining the name of the relationship method and suffixing the method name with _id. So when I was naming my relationship
Yes, which is why I linked to the relevant portion of the user manual. I'm glad you "figured it out" :)
Level 10
Ha @cronix I will mark you are best answer :). Thanks for your help!
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