[Question] Schema Builder Foreign Keys

I am trying to understand how to add foreign key constraints in the schema builder. Having spent some time reading over https://github.com/laravel/framework/blob/master/src/Illuminate/Database/Schema/Blueprint.php and https://github.com/laravel/framework/blob/master/src/Illuminate/Database/Schema/Grammars/MySqlGrammar.php, I am afraid I still can't understand how to add foreign keys.

The argument to the foreign key can be a string or array which is referenced internally as $columns. Is this the name of the column on the table with the foreign key, or the name of the key on the relational table?

Many thanks!

Schema::create('comments', function($table)
{
    $table->increments('id');
    $table->integer('post_id')->foreign('post_id');
    $table->text('content');
    $table->timestamps();
});

[taylorotwell]

Please post question on the Laravel forums. http://forums.laravel.io

The issues are reserved for true "issues" or bugs.