Laravel "Cannot add foreign key constraint" - Migrate - laravel

Question

I have a problem with a foreign key.
I have a user who has a sex:
My migration users :
public function up()
{
Schema::create('users', function (Blueprint $table) {
$table->increments('id');
$table->string('name');
$table->string('nom');
$table->string('prenom');
$table->string('adresse');
$table->integer('cp');
$table->string('ville');
$table->string('email')->unique();
$table->string('password');
$table->rememberToken();
$table->timestamps();
$table->tinyInteger('admin')->nullable();
});
Schema::table('users', function ($table) {
$table->integer('sexe_id')->unsigned();
$table->foreign('sexe_id')->references('id')->on('sexes');
});
}
/**
* Reverse the migrations.
*
* #return void
*/
public function down()
{
Schema::drop('users');
}`
My sexe migration :
/**
* Run the migrations.
*
* #return void
*/
public function up()
{
Schema::create('sexes', function (Blueprint $table) {
$table->increments('id');
$table->string('libelle');
$table->timestamps();
});
}
/**
* Reverse the migrations.
*
* #return void
*/
public function down()
{
Schema::drop('sexes');
}
My sexes seeder :
class SexesTableSeeder extends Seeder
{
/**
* Run the database seeds.
*
* #return void
*/
public function run()
{
DB::table('sexes')->insert([
[
'libelle' => 'Homme',
'created_at' => date('Y-m-d H:i:s'),
'updated_at' => date('Y-m-d H:i:s'),
],
[
'libelle' => 'Femme',
'created_at' => date('Y-m-d H:i:s'),
'updated_at' => date('Y-m-d H:i:s'),
]
]);
}
}
My users seeder :
class UsersTableSeeder extends Seeder
{
/**
* Run the database seeds.
*
* #return void
*/
public function run()
{
DB::table('users')->insert([
[
'name' => 'admin',
'nom' => 'Virlois',
'prenom' => 'Peter',
'sexe_id' => 1,
'email' => 'admin#admin.fr',
'adresse' => '12 rue Jean Rostand',
'cp' => 90000,
'ville' => 'Belfort',
'password' => bcrypt('admin123'),
'created_at' => date('Y-m-d H:i:s'),
'updated_at' => date('Y-m-d H:i:s'),
'admin' => 1,
],
[
'name' => 'test',
'nom' => 'Mennegain',
'prenom' => 'Mathieu',
'sexe_id' => 1,
'email' => 'test#test.fr',
'adresse' => '12 rue Jean Rostand',
'cp' => 90000,
'ville' => 'Belfort',
'password' => bcrypt('test123'),
'created_at' => date('Y-m-d H:i:s'),
'updated_at' => date('Y-m-d H:i:s'),
'admin' => 0,
]
]);
}
}
My database seeder :
class DatabaseSeeder extends Seeder
{
/**
* Run the database seeds.
*
* #return void
*/
public function run()
{
$this->call(SexesTableSeeder::class);
$this->call(UsersTableSeeder::class);
$this->call(SaisonTableSeeder::class);
$this->call(ProduitTypeSeeder::class);
$this->call(SportsTableSeeder::class);
$this->call(ProduitsTableSeeder::class);
}
}
When i run : php artisan migrate:refresh -seed
I have this error :
[Illuminate\Database\QueryException]
SQLSTATE[HY000]: General error: 1215 Cannot add foreign key constraint (SQL
: alter table `users` add constraint `users_sexe_id_foreign` foreign key (`
sexe_id`) references `sexes` (`id`))
[PDOException]
SQLSTATE[HY000]: General error: 1215 Cannot add foreign key constraint

Answer 1

The order of migrations is super important. From what you posted you run the users migration first and in that same migration you try to create a users table and alter a table. the other table sexes doesn't exist
($table->foreign('sexe_id')->references('id')->on('sexes');)
so that is why you get a error.
I suggest separating the migrations in order to run users, sexes, alter users or sexes, users and alter in the same migration, but this is not a good way to do things, I mean to mix migrations (create and alter).

Answer 2

Probably there are nothing with id 1 in sexes table and sexe_id => 1 generating this error. In your UsersTableSeeder rather than hardcoding 'sexe_id' => 1 query your sexes table for any row and use that dynamic id.