I have a column in a table which I would like to update by using a calculation involving other columns in the same table. For example ColumnA * ColumnB updates ColumnC. I have got the calculation I want to use by building it in a query and it works. However, I don't know how to make it update the column I want the result to go into. I have tried to put the calculation in the update criteria for the column, but it doesn't work. Am I on the right track or totally wrong?