primary key in migration laravel code example

Example 1: laravel model string primary key

class UserVerification extends Model
{
    protected $primaryKey = 'your_key_name'; // or null

    public $incrementing = false;

    // In Laravel 6.0+ make sure to also set $keyType
    protected $keyType = 'string';
}

Example 2: laravel migration drop foreign keys

$table->dropIndex(['state']); // Drops index 'geo_state_index'