I don't have any experience, but you do math in tsql, So you just execute a giant tsql command, that gets the current value, does math, and updates it with a new value, all in tsql. [EDIT] Took a while to find a decent example of sql math, that would apply to you http://www.mssqltips.com/sqlservertip/1547/calculating-mathematical-values-in-sql-server/[^]

You also posted in Q&A: Multiple bookings using arraylist[^] - already answered there. Sandeep Mewara [My last article]: Server side Delimiters in ASP.NET[^]

Since contents may have any type of symbols, I suggest that you convert it into Base64, and then you can use either comma or ';', or many other symbols as delimiters, from those that are not included into Base64 itself.