Laravel: one to one relationship becomes one to many relationship

Question

When I create a one-to-one relationship migration, laravel creates a one-to-many relationship.

PHP 7.1 & MySQL 5.7

The models are: Persona & User.

Persona:

public function user()
{
    return $this->hasOne('App\User', 'persona_id', 'id');
}

User:

public function persona()
{
    return $this->belongsTo('App\Persona', 'persona_id', 'id');
}

Migrations:

Schema::create('users', function (Blueprint $table) {
    $table->increments('id');
    $table->integer('persona_id')->unsigned();
    $table->foreign('persona_id')->references('id')->on('personas')->onDelete('cascade');
    $table->unique(['persona_id', 'id']);
    $table->string('email')->nullable()->unique();
    $table->string('password')->nullable();
    $table->rememberToken();
    $table->timestamps();
});


Schema::create('personas', function (Blueprint $table) {
    $table->increments('id');
    $table->string('tipo');
    $table->integer('cedula')->unsigned()->unique();
    $table->string('primer_nombre');
    $table->string('segundo_nombre')->nullable();
    $table->string('primer_apellido');
    $table->string('segundo_apellido')->nullable();
    /* Agregar demas campos que se requieran */
    $table->timestamps();
});

How can I make the relationship created in the database one by one and not one to many? Currently this is allowing me to save more than one user per person.

Thanks.

Answer 1

Put the unique index only on persona_id:

$table->unique('persona_id');