sorry,
i don't think php is the solution here, php can't force your ms access db to export itself to a csv file or more files
i had the same issue and I don't recommend trying to upload a ms access db directly in case it's big, use navicat instead
http://www.navicat.com/
personal story related to your question
here's my story, I had an ms acces db about 200 Mb in size, two tables with ~1000 rows and ~50000 rows and many other useful tables linked to these tables, I simply had to configure my connection to mysql server then upload that file, it didn't take long and my data was migrated without any data loss to mysql , bear in mind that you should pay attention to import forms and such, in case you'd like to update the existing database, bear in mind that you can set column mappings (old ms access db to new mysql structure)