newbie questions

Guys, I am fairly new to PHP. Here are a few questions, if anybody can answer it will help me get started. Thanks I am trying to build a website and I would like to do the following in my scripts 1. I want to return response to the browser and AFTERWARDS make a log entry in to a database. I need this so user can experience a fast response. 2. If the database update fails, I want to ignore it (since it is just log entry). Something like try-catch construct in Java. This is more important if item1 mentioned above is not possible. Essentially whether I make a database entry or not, I must return a valid response to user. 3. Is there something like connection pool in php? Do usually people open/close database connection for every request (I doubt that, it sounds really slow). Some code samples or pointers to documentation for the above would also be very helpful. Thanks Ravi