The response data is a list, with either a label or value column or both. The label column is displayed in the suggestion menu. The value will be inserted into the hidden input element after the user selected something from the menu. If just one column is specified, it will be used for both, eg. if you provide only value-properties, the value will also be used as the label.
Single quoted text. Column name but exist in list returned by the response handling webroutine.