the database in iphone app is not updated if i install update app from testflight or diawi

my app is on local database using sqlite. suppose the table in the database has 3 columns and i installed this app using either testflight or diawi. Now i add 4th column in the table and now if i installed this app through testflight or diawi then i cant see the updated database in the app (in iphone). I need to uninstall previuos version and fresh install the app from testflight or diawi, then i can see the updates which i changed in the app.

Does anyone facing same problem ???

Thanks in advance .......