Shell scripting and programming

Guys,

I require data to be fetched for 12 months, but the data stored in DB is only for 6 months...I had a script which fetches the data from the DB, but I want to append the previous 6 months data as well for the fetched data...

I had a file which contains data from Dec 12 till April 2013 and my script fetches data for last 6 months.... I want to have data from Dec 12 till date in one file.....[RIGHT][/RIGHT]