Column Views are used to select the columns that you want displayed in a table. You can select the default view for new tables via the "Column Views" menu. The current view on an existing table can be changed or edited then saved via the context menu (right-click) on the table header.

When editing a Column View there are two sets of check boxes "Show Only" and "Hide". "Show Only" will only show the selected columns which is useful if you are likely to add nodes to a table that have additional columns and you do not wish to have the new columns displayed. "Hide" will only hide the selected columns and when a node is viewed with columns not in the list the new columns will also be displayed.