Simple question: I'm new to Laravel. I have this migration file:
Schema::create('lists', function(Blueprint $table) {
$table->increments('id');
$table->string('title', 255);
$table->integer('user_id')->unsigned();
$table->foreign('user_id')->references('id')->on('users');
$table->timestamps();
});
我想把它更新为增加onDelete('cascade')个.
What's the best way to do this?
首先，你必须将user_id字段作为索引:
$table->index('user_id');
After that you can create a foreign key with an action on cascade:
$table->foreign('user_id')->references('id')->on('users')->onDelete('cascade');
If you want to do that with a new migration, you have to remove the index and foreign key firstly and do everything from scratch.
在down()函数中，您必须执行此操作，然后在up()中执行我在上面编写的内容:
$table->dropForeign('lists_user_id_foreign');
$table->dropIndex('lists_user_id_index');
$table->dropColumn('user_id');