Why am I getting the error in post? Laravel

Question

So I'm trying to create a simple REST API using Laravel. While testing out the API with creating new items to the database I'm receiving an error:

Illuminate\\Database\\QueryException: SQLSTATE[23000]: Integrity constraint violation: 1452 Cannot add or update a child row: a foreign key constraint fails ( world . cities , CONSTRAINT cities_ibfk_1 FOREIGN KEY ( CountryCode ) REFERENCES country ( Code )) (SQL: insert into cities ( Name , CountryCode , District , Population , updated_at , created_at ) values (Valhalla, vlh, Ragnar Alley, 200000000, 2020-02-19 01:07:26, 2020-02-19 01:07:26)) in file C:\\xampp\\htdocs\\myapp\\vendor\\laravel\\framework\\src\\Illuminate\\Database\\Connection.php on line 669

here's the Controller:

      public function createCity(Request $request) {
        $city = new City;
        $city->Name = $request->Name;
        $city->CountryCode = $request->CountryCode;
        $city->District = $request->District;
        $city->Population = $request->Population;
        $city->save();

Model:

class City extends Model
{
    protected $table = 'cities';

    protected $fillable = ['Name', 'CountryCode', 'District', 'Population'];
}

Help would be appreciated as I can't figure out why I'm getting the error after POST. Thanks in advance.

Answer 1

You try to add vlh as contry_code value into your model .but this field refrence to another model that have country name and in that table there is not any record with this condition and vlh value is unknown or it.

You can romve relation between these models (if it is possible) or first find the id of country that has that code and then insert it into your model.