findOrFail Laravel 5 function for specific field
Stefan Bogdanescu
Founder & Senior Architect · 2026-06-29
# Mastering `findOrFail()`: Finding Records by Custom Fields in Laravel Eloquent
As developers working with Laravel and Eloquent, we often rely on powerful methods like `findOrFail()`. This method is designed to be concise, automatically handling the database lookup and throwing a `ModelNotFoundException` if no record is found. However, when dealing with custom schemas—where your primary key isn't the default `id` column—this behavior can become confusing.
The core issue you are facing is that Eloquent, by default, assumes the `id` column is the primary key for all operations, including finding records via methods like `findOrFail()`. When you call `$model::findOrFail($value)`, Eloquent internally translates this into a query based on the defined primary key. If your custom field (`postal`) is what you want to use for lookup, you need to explicitly guide Eloquent to do so.
This post will dive deep into why this happens and provide the most robust, developer-friendly solutions for finding records in Laravel when using non-standard primary keys.
---
## Understanding the Default Behavior of `findOrFail()`
When you execute `$model::findOrFail($postal)`, Eloquent constructs a query roughly equivalent to:
```sql
SELECT * FROM geo_postal_us WHERE id = [the_value_of_postal] LIMIT 1;
```
This is because, unless explicitly told otherwise, the model assumes the column named `id` holds the primary key. If your table structure defines `postal` as the unique identifier you wish to search by, the default behavior will fail to find the record unless a record coincidentally has an `id` matching the desired postal code—which is rarely the case.
## Solution 1: Redefining the Primary Key in the Model (The Eloquent Approach)
The cleanest way to fix this for *all* subsequent Eloquent operations on that model is to inform the model itself which column serves as the primary key. You do this by setting the `$primaryKey` property within your Eloquent model class.
For your `Geo_Postal_us` model, you would modify it like this:
```php
// app/Models/Geo_Postal_us.php
namespace App\Models;
use Illuminate\Database\Eloquent\Model;
class Geo_Postal_us extends Model
{
/**
* The primary key for the model.
*
* @var string
*/
protected $primaryKey = 'postal'; // <-- Explicitly setting the custom PK
/**
* The attributes that are mass assignable.
*
* @var array
*/
protected $fillable = ['name', 'city', 'postal']; // Example fillables
// ... other model methods
}
```
Once you set `$primaryKey = 'postal'`, Eloquent automatically adjusts its internal queries. Now, when you use `findOrFail()`, it will correctly search the `postal` column:
```php
// This now works as intended!
$get_all = Geo_Postal_us::findOrFail($postal);
```
This approach is highly recommended because it makes your model behave consistently with its actual database structure, following best practices outlined by the Laravel team. For deeper dives into Eloquent relationships and core features, always refer to resources like [laravelcompany.com](https://laravelcompany.com).
## Solution 2: Using the Query Builder Directly (The Explicit Approach)
If you cannot or do not want to modify the model's primary key definition (perhaps because other parts of your application rely on the standard `id` for foreign keys), the most direct and explicit solution is to bypass the Eloquent model methods temporarily and use the underlying Query Builder. This gives you absolute control over the SQL being executed.
Instead of relying on `$model::findOrFail($value)`, you explicitly tell the query builder which column to search against:
```php
use Illuminate\Support\Facades\DB;
$postal_value = '90210';
// Find the record where the 'postal' column matches the value, and retrieve the full model.
$result = DB::table('geo_postal_us')
->where('postal', $postal_value)
->first(); // Use first() or firstOrFail() depending on preference
if (!$result) {
throw new \Exception("Postal code not found.");
}
// If you still want the Eloquent object:
$model = new Geo_Postal_us;
$model->setAttribute('postal', $postal_value); // Manually set the PK value if needed for saving
$model->fill($result); // Populate the model instance with the found data
```
While this method requires more explicit coding, it is extremely powerful. It ensures that your search logic directly reflects your database schema, regardless of how Eloquent might be configured elsewhere in the application. This