Inserting a New Column
Columns can be inserted before or after the currently selected column. To select a column, click anywhere within the column.
To insert a column before the selected column click the Insert Column Before button in the editor toolbar or right-click Context Menu.
To insert a column after the selected column click the Insert Column After button in the editor toolbar or right-click Context Menu.
Deleting a Column
Select a column by clicking anywhere within the column. Click the Delete Table Column button in the editor toolbar or right-click Context Menu