[galaxy-dev] Adding column names to output

Hello, I am extracting data from a database and displaying the result in tabular format. I would like to have the header in the output as column names, so that when I do 'join' I know which columns I am referring to. Currently, it only displays as 1, 2, 3. How do I assign column names to the header? Whatever columns I search in the database can be the header in my output. I tried searching around but couldn't find the solution. Thank you. Batsal.