Create A Database That Logged In Users Could Access And Add Customization?

I want to make a game where a user logs in. Once the user logs in, they have access to a database (let's just say a database of weapons). They could choose a certain amount of "weapons" and every time they log in, they still have the same weapons, regardless of cookies, because the "weapons" are linked to their username. Then the users could use their weapons to battle other users. Also, the user's username keeps track of their wins and losses. I have newb to basic flash knowledge (I took an animations class); I could animate, make buttons, websites, etc. Does anyone have some insight that could point me in the right direction?