ENUM
User sorting enum
enum UserOrderKeys {EMAIL_ASCEMAIL_DESCFIRST_NAME_ASCFIRST_NAME_DESCLAST_NAME_DESCLAST_NAME_ASCCREATED_AT_DESCCREATED_AT_ASCUPDATED_AT_DESCUPDATED_AT_ASCGROUP_NAME_ASCGROUP_NAME_DESCPROVIDER_NAME_ASCPROVIDER_NAME_DESCNEXT_APPT_DATE_ASCNEXT_APPT_DATE_DESC}