Sql Server Row Concatenation

I have a table (table variable in-fact) that holds several thousand (50k approx) rows of the form: group (int) isok (bit) x y 20 0 1 1 20

Solution 1:

You can treat the bit as a string ('0', '1') and deploy one of the many string aggregate concatenation methods described here: http://www.simple-talk.com/sql/t-sql-programming/concatenating-row-values-in-transact-sql/