add another colum in a database?

Question

i have created a database that hooks in with my program, problem is i forgot to add in a colum .... i kmnow how to do this by editing the table, problem is how do i then get it to the program and to act like the others already on there?
wil i need to create a new data source? i tried this once and then NONE of them worked, none of the colums would save the changes.
&note* .. the new item i created appears in the database exporer window but NOT in the data source exporer .. im not sure what to do

thanks