If you have used the Show/Hide Fields tool in a dataview and want to revert back to the defaults, you can show all columns in a dataview in their original order by right-clicking on a cell or column heading and choosing Show All.

With an item in a column selected in a dataview, you can highlight the entire column by pressing Ctrl+Space on your keyboard.

You can clear cells by right-clicking on a highlighted range of cells and choosing Clear.

If you want to create a new blank field to fill with data, modify the underlying table using Dataview>Table>Modify.  Then, click Add Field and set up the field as you need.

If a field name contains spaces or other special characters or starts with a digit, you must put square brackets around it. For example a field called “Age <5"  will need to be "[Age <5]" in your formula. Fields that require brackets will automatically display with them in the Formula Builder Field List.