Asterisk has the following fields
   CREATE TABLE `cdr` (
  `calldate` datetime NOT NULL default '0000-00-00 00:00:00',
  `clid` varchar(80) NOT NULL default '',
  `src` varchar(80) NOT NULL default '',
  `dst` varchar(80) NOT NULL default '',
  `dcontext` varchar(80) NOT NULL default '',
  `channel` varchar(80) NOT NULL default '',
  `dstchannel` varchar(80) NOT NULL default '',
  `lastapp` varchar(80) NOT NULL default '',
  `lastdata` varchar(80) NOT NULL default '',
  `duration` int(11) NOT NULL default '0',
  `billsec` int(11) NOT NULL default '0',
  `disposition` varchar(45) NOT NULL default '',
  `amaflags` int(11) NOT NULL default '0',
  `accountcode` varchar(20) NOT NULL default '',
  `uniqueid` varchar(32) NOT NULL default '',
  `userfield` varchar(255) NOT NULL default ''
) ENGINE=MyISAM DEFAULT CHARSET=latin1;
Most field names are self explanatory, however some fields contain non-self-explanatory data.  For instance dst = "s", is anyone aware of documentation that explains this and other pieces of data logged in the CDR table?