Skip to main content

Laravel Eloquent Relationships Tip

So...I just discovered a "gotcha" with Eloquent relationships that I wish I had known when I created my migrations and data files.  So this would be good for other developers to know in advance as well.  The essence of the problem has to do with the potential name conflict between an eloquent property and a relationship method.  Here's a look at the problem I ran into:

1) I have a "states" table with the following columns: id (auto-numbered), name, abbreviation.
2) I have a "companies" table with the following columns: id, name, address, city, state, zip.

Notice that I didn't use a "state_id" column in my "companies" table.  Instead, I insert the state abbreviation and label it as "state".  I made this decision because I fairly often run queries directly against tables and I want to avoid having to type out the JOIN statement for a simple, 2-character field.

So that's all fine except when I want to create a relationship in my Company model that makes grammatical sense:

public function state()
{
    return $this->belongsTo('App\State', 'state', 'abbreviation');
}
...which yields the code:
$company= Company::with('state')->find($id);
...which can be referenced like so:
$company->state->name;


Unfortunately, the above statement displays nothing, even though the query it produces is fine.  This is because there is a company property conflicting with a company method:
$company->state; // = 'MD'
$company->state->name // = NULL
In other words, Eloquent isn't able to translate the property to a method when used as such.

The simplest solution to this (without creating some awkward grammar) is to change the "state" column in the "companies" table to "state_abbreviation".  That will remove the conflict between property and method.

A better solution would have been to start with a states table where the ID was the state abbreviation then have "state_id" in the companies table reference the state.id field.  This is ideally how Laravel Eloquent likes to do things.  Unfortunately, once you get far enough into a project, a change like that turns into a lot of code changes.  So note to self for next time!

Comments

Post a Comment

Popular posts from this blog

jQuery noUIslider Pip Label Customization

Recently, I was tasked with creating a slider element for a user to select their credit rating, of which the user can select from among: 'Poor', 'Fair', 'Good', 'Excellent' and 'Not Sure'.  Several problems presented themselves here: A drop-down box would be better, but that's not what the requirements specified. I already have several numeric sliders on my page and I want them all to match. I selected the jQuery noUi Slider library to create the numeric sliders. noUi Slider does not support string values - only numeric values. The "pips" (slider scale/labels) also does not support string values. Since the solution involved shifting my mindset, I wanted to document it here for future reference and maybe to help someone facing the same requirements. Here's my solution: Since there is really no numeric correlation to credit score (especially considering one of the options is "Not Sure"), I will just u...
Post a Comment
Read more

How to Create a new Case Record Type in Salesforce

Here are the specific steps for adding a case record type. Some steps may vary by organization but the process should be pretty similar to what is shown here. 1) Create a new page layout 2) Add any new case statuses to picklist 3) Edit case statuses that should indicate case is "closed" 4) Add any new case types to picklist 5) Add any new case reasons to picklist 6) Add any new case origins to picklist 7) Add any new fields to case object 8) Under Record Types, ensure the picklists have the correct values (i.e. - Reason/Type/Origin) 9) Within the Type field, edit "Reason" field dependencies matrix and add new reason(s) to types 10) Create a new support process (if not reusing an existing one) 11) Create the new record type (enable for all profiles) 12) Finalize the page layout (if needed) and check "Default" in Case Assignment checkbox under Layout Properties 13) Create approval queues (if needed) 14) Set up approv...
Post a Comment
Read more

Java...Still Sucking Hard, Compared to Other Languages

I know there are a bunch of Java devotees out there.  I frequently have them evangelizing the language to me as a "strongly-typed" language that is so much better than loosely-typed languages, like PHP.  So here is something that just came up for me and I'd like to ask all those devotees WHY they like the type enforcement. Here's a bit of code to store a random integer as a string in PHP: $myString = rand(5); And now...the Java version: String myString = String . valueOf ( Integer . valueOf ( Math . random () * 10000 )); I get it...you need to keep your phony-baloney job and writing more  code and making it more complicated can help you keep it out of the hands of less "intelligent" programmers. As for myself, I will always prefer a language that lets me write shorter, more eloquent code and get my applications built faster.  But then...maybe I'm just simple.
Post a Comment
Read more