Not for 'how-to' coding questions but PHP theory instead, this forum is here for those of us who wish to learn about design aspects of programming with PHP.
The principal module for using php to generate or manipulate flash would be the ming libraries - there is a lot of information in the ming section of the manual or through googling.
Is one of the areas that I want to do some developing in, just haven't had the time yet.
It depends on what you want to do with flash. However, I was working for a company that developed the games in flash, and the logic in PHP, and it worked out well.
You'd need to be a little more specific in your question. But I remember making a Flash front-end for poll engine in PHP early as Flash 4, and it's only gotten easier now.
if you just want to read the flash file from a database just read it and before echoing or printing the data from the db use the function header as follows: header("Content-type: application/x-shockwave-flash");