php/mySQL capabilities

Hi all, I am a newcomer to php/mySQL but really like what I have seen so far. I am interested in working on a project which requires a web based db. I am just wondering if php/MySQL would be suitable for my requirements. The DB is going to contain several hundred seperate tables, and certain records must be updateable by certain people (with unique password) only. There will be about 200 - 300 seperate account holders on the DB each one needs to be able to update their and only their information stored in the DB from their own offices around the country (Ireland) over the web. Although the frequency of updates would be low, say 1 update per account per week, i.e. 200-300 updates per week. I am just wondering if php/mySQL can handle these sort of requirements - updates from multiple locations over the web and the whole idea of each account holder only being able to update information pertaining to themselves in the DB. Thanks in advance, any advice would be greatly appreciated, Paul Caheny.