The type of data to store, associated with this button. If “none”, no data is stored regardless of user interaction. If “boolean”, then “true” will be stored if the button was pressed and “false” will be stored if the button was displayed to the user but they chose not to press it. If “datetime”, then pressing the button will store the timestamp for the point in time when the button was pressed. Note that if the column type is set to “datetime” and the field is not marked as optional then the user will not be able to complete the form until they press the button.