Access spreadsheet content via database

I’d like to realize a software to provide spreadsheet content to a user via an internet database. Spreadsheet content should be stored as string (not as files) to search through all data easily, preferred as xml code, and most preferred as OfficeOpenXML code. Content: values, formats, cell format/styles, simple shapes. Database shall be MySQL and store besides spreadsheet content also storage time, user id, history (how content was modified) and so on. One shall be able to “read” to but also to write in the database. Reading and writing shall work “between” the users open spreadsheet (client side) and the database (server side). I wonder what’s the best way to create the reading/writing part! Following ideas/ways I see: A) Run a program – as spreadsheet add-in or as an operating system service (Windows service etc.) – on users PC to access the database (login information stored in ini-file); load data from database into this program, access user’s spreadsheet (for MS Excel via MS Interop) and write loaded data into user’s spreadsheet B) Establish a website with some tool installed like PHPExcel, access the database via this website (login information = login to website), with PHPExcel create a new spreadsheet model on website server, write loaded data into this model and get user to copy/paste from model into his spreadsheet (Are there other options?) From deployment point of view I’d go for option B) but I don’t like the idea to be dependent on PHPExcel. Or are there other php libraries to get this done? For both options I wonder if it is possible not to write into the spreadsheet but to create the spreadsheet file, access the xml code of the file and write/paste data from database directly into this code (which makes OfficeOpenXML code necessary). To get started focussing on Windows would be o.k.