<b>FOAF:</b>

<verbatim>
   * aimChatID
   * based_near
   * birthday
   * family_name
   * firstName
   * gender
   * homepage
   * icqChatID
   * maker
   * mbox
   * msnChatID
   * nick
   * phone
   * yahooChatID
</verbatim>

<b>SIOC:</b>

<verbatim>
   * has_container
   * has_creator
   * id
   * link
   * topic
</verbatim>

<b>vcard:</b>

<verbatim>
   * ADR
   * BDAY
   * CATEGORIES
   * EMAIL
   * FN
   * N
   * NICKNAME
   * UID
</verbatim>

<verbatim>
PREFIX sioc: <http://rdfs.org/sioc/ns#>
PREFIX sioct: <http://rdfs.org/sioc/types#>
SELECT DISTINCT ?attribute
WHERE
  {
    ?forum a sioct:AddressBook .
    ?forum sioc:container_of ?post .
    ?post ?attribute ?o  
  }
</verbatim>

---++++Sample Data (Live Query Results)

   * View Query Results [[http://demo.openlinksw.com/sparql?default-graph-uri=&should-sponge=&query=PREFIX+sioc%3A+%3Chttp%3A%2F%2Frdfs.org%2Fsioc%2Fns%23%3E%0D%0APREFIX+sioct%3A+%3Chttp%3A%2F%2Frdfs.org%2Fsioc%2Ftypes%23%3E%0D%0ASELECT+DISTINCT+%3Fattribute%0D%0AWHERE%0D%0A++%7B%0D%0A++++%3Fforum+a+sioct%3AAddressBook+.%0D%0A++++%3Fforum+sioc%3Acontainer_of+%3Fpost+.%0D%0A++++%3Fpost+%3Fattribute+%3Fo++%0D%0A++%7D&format=text%2Fhtml&debug=on][(via SPARQL Protocol URL)]]
   * View Query Results [[http://demo.openlinksw.com/view/?format=application%2Frdf%2Bxml&maxrows=50&query=%0APREFIX%20sioc%3A%20%3Chttp%3A%2F%2Frdfs.org%2Fsioc%2Fns%23%3E%0APREFIX%20sioct%3A%20%3Chttp%3A%2F%2Frdfs.org%2Fsioc%2Ftypes%23%3E%0ASELECT%20DISTINCT%20%3Fattribute%0AWHERE%0A%20%20%7B%0A%20%20%20%20%3Fforum%20a%20sioct%3AAddressBook%20.%0A%20%20%20%20%3Fforum%20sioc%3Acontainer_of%20%3Fpost%20.%0A%20%20%20%20%3Fpost%20%3Fattribute%20%3Fo%20%20%0A%20%20%7D&endpoint=/sparql&maxrows=50&default-graph-uri=][(via iSPARQL Results URL)]]
   * View Query Editor [[http://demo.openlinksw.com/isparql/?query=PREFIX%20sioc%3A%20%3Chttp%3A%2F%2Frdfs.org%2Fsioc%2Fns%23%3E%0APREFIX%20sioct%3A%20%3Chttp%3A%2F%2Frdfs.org%2Fsioc%2Ftypes%23%3E%0ASELECT%20DISTINCT%20%3Fattribute%0AWHERE%0A%20%20%7B%0A%20%20%20%20%3Fforum%20a%20sioct%3AAddressBook%20.%0A%20%20%20%20%3Fforum%20sioc%3Acontainer_of%20%3Fpost%20.%0A%20%20%20%20%3Fpost%20%3Fattribute%20%3Fo%20%20%0A%20%20%7D&endpoint=/sparql&maxrows=50&default-graph-uri=][(via iSPARQL Visual Query Editor URL)]]