Get a single database column with Eloquent's value() method

Imagine this scenario: you want to send an email, you have the user's email address, but you need their name too. You could get the name by retrieving the model from the database:

$name = User::firstWhere('email', $email)?->name;

if ($name !== null) {
   //
}

The code above isn't very efficient. Not only will this Eloquent query select columns you don't need, it also eager loads any relations the model has defined in the $with property.

A better way to get a single value from the database is by using Laravel's built-in value() method:

$name = User::where('email', $email)->value('name');

if ($name !== null) {
   //
}

The value() method selects a single column, and only returns the first row. It is the most efficient way to select a single value from your database. The Eloquent query above runs the following SQL query:

select `name` from `users` where `email` = 'test@example.com' limit 1

The value() method also applies any $casts you have defined on the model:

class User
{
    public $casts = [
        'status' => UserStatusEnum::class,
    ];
}

$status = User::where('email', $email)->value('status');

if ($status === UserStatusEnum::ACTIVE) {
   //
}