In a table there are two columns with values. I want to insert another column so that when I enter values in the original two columns the sum will automatically be entered in the new column.

In a table there are two columns with values. I want to insert another column so that when I enter values in the original two columns the sum will automatically be entered in the new column.

1. Until Access 2010 comes out this is a very, very bad idea and violates the rules of normalization.

2. You do not store the calculated values if you have the values available to recreate the calculation.

3. USE A QUERY when you need those values. Build a query that has that third column and use it where you would use the table (you can use a query in 99.99% of the places you would use a table).