get a unique phone # (10 digit) from a table. SLOW

Platform: Unixware 2.0,Digital 2 CPUS (Pentium 90) SE, I4GL 80+ Users. One of the menu option is GET A # To Call Code is not exact. Just the concepts are given called = 1 means this num can be used called = 0 means this num has been already used what this code does is: --> get a num from the table select phone_num from call_list into num_800 where called = 1 --> update the table so that other users dont get the same num update call_list set (user_name, date_called,called) = (username,TODAY,0) where phone_num = num_800 Usually we have to load 12,000 to 20,000 nums into this table everyday we do daily: clean up this table, update statistics, bcheck all tables. We have about 80+ users: Problem 1: Sometimes takes more time to get a # problem 2: Sometimes two or more people get the same #