Laravel migration where id column not named "id" causes error

Question

How do I make an id / primary key column that's different from "id"? When I try it it creates an error.

class CreateEmployeesTable extends Migration
{
// ...
    public function up()
    {
        Schema::create('employees', function (Blueprint $table) {
            $table->id('employee_id');
            $table->string('first_name', 100);
            $table->string('last_name', 100);
            $table->string('email', 200);
            $table->timestamps();
        });
    }
// ...
}

Trying it out:

php artisan tinker
Psy Shell v0.10.8 (PHP 7.3.20 — cli) by Justin Hileman
>>> $employee = new App\Models\Employee
=> App\Models\Employee {#3452}
// ...
>>> $employee->save();
<warning>PHP Warning:  oci_execute(): ORA-00904: "ID": invalid identifier in <path>Statement.php on line 159</warning>
Yajra\Pdo\Oci8\Exceptions\Oci8Exception with message 'Error Code    : 904
Error Message : ORA-00904: "ID": invalid identifier
Position      : 132
Statement     : insert into "EMPLOYEES" ("FIRST_NAME", "LAST_NAME", "EMAIL", "UPDATED_AT", "CREATED_AT") values (:p0, :p1, :p2, :p3, :p4) returning "ID" into :p5
Bindings      : [Roger,Rabbit,rrabbit@somewhere.com,2021-11-04 22:13:56,2021-11-04 22:13:56,0]

Answer 1

When you use a primary key in a table other than id you need to specify it in the model class with

class Employee extends Model
{
    /**
     * The primary key associated with the table.
     *
     * @var string
     */
    protected $primaryKey = 'employee_id';
}