ios - how to get the list of keys in a Parse.com query? -

is there option list of existing keys instead of getting of them in query?

i'm using pfquerytableviewcontroller build table view

i have parse.com class contains list of keys can duplicate

need build table view show list of unique keys class

can using parse querying methods while overriding func queryfortable() -> pfquery

using swift ios

here can find documentation: basic queries