I’m not able to create the relationship between the tables through the migrations of Laravel

Question

I am using the Multi Tenancy in Laravel, so I created the Migrations, without relationship between table was working normal, when I related that started the error.

I thought it was the execution order of the migrations, so I renamed it to execute in the correct form, but the error continued.

Migrations -> 2019_08_07_024917_list

    public function up()
    {
        Schema::create('tbd_lista', function (Blueprint $table) {
            $table->bigIncrements('id');
            $table->string('nome')->nullable();
            $table->timestamps();
        });
    }

Migrations -> 2019_08_08_024935_card

public function up()
    {
        Schema::create('tbd_cartao', function (Blueprint $table) {
            $table->bigIncrements('id');
            $table->string('nome',100)->nullable();
            $table->integer('tbd_lista_id')->unsigned();
            $table->foreign('tbd_lista_id')->references('id')->on('tbd_lista');
            $table->longText('descricao');
            $table->boolean('arquivar');    
            $table->dateTime('data');
            $table->timestamps();
        });
    }

Error:

"SQLSTATE[HY000]: General error: 1215 Cannot add Foreign key Constraint (SQL: alter table tbd_cartao add Constraint tbd_cartao_tbd_lista_id_foreign Foreign key (tbd_lista_id) References tbd_lista (id))"

Answer 1

Leave to make the relation between the tables in their models, in the development, in the code, and not in the database. If the problem is because of deletion use $table->softDeletes() and not delete nda.

This helps in the subsequent audit, statistics and even in the retrieval of information.

Take a look at these articles:

https://medium.com/@hernandev/always-use-foreign-no-mysql-e24b4e2187f5

https://medium.com/@lemesdaniel/o-porqu%C3%AA-de-eu-n%C3%A3o-use foreign-no-mysql-2e0179af4b2c

Answer 2

How you ta using bigIncrements you need to pass in the other table bigInteger follows its own changed code:

public function up()
    {
        Schema::create('tbd_cartao', function (Blueprint $table) {
            $table->bigIncrements('id');
            $table->string('nome',100)->nullable();
            $table->bigInteger('tbd_lista_id')->unsigned();
            $table->foreign('tbd_lista_id')->references('id')->on('tbd_lista');
            $table->longText('descricao');
            $table->boolean('arquivar');    
            $table->dateTime('data');
            $table->timestamps();
        });
    }

Answer 3

trade in $table->integer('tbd_lista_id')->unsigned(); for $table->bigInteger('tbd_lista_id')->unsigned(); to remain identical to the key Primary of the related table.

Answer 4

I have already gone through this several times and my solution was to backup the tables delete the database and run php Artisan Migration again, why for some reason Laravel does not accept new tables with Foreign key.