I am reading "Build Your Own Database Driven Web Site, 4th Edition".
In chapter 3 (page 109) the book introduces a rather strange way to use a form action.
<form action="" method="post">
The book further explain that by sending an empty action, the form is submitted to the same PHP script.
In chapter 4 (page 132) the book introduces:
<form action="?" method="post">
This time the book explains that by using action="?" any data after the ? in the url will be deleted, basically deleting and GET information.
I am a bit confused as I cannot find any documentation around explaining these two ways of submitting a form. Can anyone point me on the right explanation/documentation in the php.net website?