title: In Android API level 8, What's "person" column in "content://sms/inbox" matching to?
body: <p>I query at Uri:  "content://sms/inbox" for reading inbox sms. Then I got these two marjor columns returned (there're other columns which not related to my question so i just skip them):
   *address - the from-person's phone number
   *person - an id value. I thought it should map to column *id in Uri "ContactsContract.Contacts.CONTENT_URI"</p>
  
  <p>I then query Uri: ContactsContract.Contacts.CONTENT_URI by condition: "id=person", hope to get the contact's display name, for some person, it works , but for many it doesn't - I then dig deeper and found there're a column "raw_contact_id" in Contacts Uri, and for those unmapped person value, it's actually mapping to this "raw_contact_id" value. </p>
  
  <p>I wonder why would this happen? Shouldn't the id be unique for contact finding? Or did i miss something to make a full query to get display name by this *person value ?? </p>