How to post on users' behalf daily
I'm trying to create an app that would send a daily post on users' behalf to his wall. I'm Using PHP. I acknowledge that I have to get the publish_stream action approved by user while authenticating.

My question is:

Do I have to use database to store the users' ids while they allow my app?
Every time I would need a valid access_token?
Is there any limit on posting as a user?

Please provide some code.
Thanks.
How to post on users' behalf daily
===

I'm trying to create an app that would send a daily post on users' behalf to his wall. I'm Using PHP. I acknowledge that I have to get the publish_stream action approved by user while authenticating.

My question is:

Do I have to use database to store the users' ids while they allow my app?
Every time I would need a valid access_token?
Is there any limit on posting as a user?

Please provide some code.
Thanks.