[SQL] Query TIME ZONE

[Raman]

Hi All, I have a query regarding Time Zone Interval   QUERY: "select current_time AT TIME ZONE INTERVAL '+5:30'" it is running fine   BUT When I take the value of interval from DB table like:   "select current_time AT TIME ZONE INTERVAL time_difference from customer_events"   here : time_difference - is my varchar column in the table customer_events. This gives me errors " parse error at or near "time_difference" at character 43 "   I tried to type cast it time_difference::text etc but it in vain.   Pls help me ... its realy urgent.   Thanks in advance   Raman Garg