jammaloo

CREATE TABLE `radacct` (
  `radacctid` bigint(21) NOT NULL AUTO_INCREMENT,
  `acctsessionid` varchar(64) COLLATE utf8_unicode_ci NOT NULL DEFAULT '',
  `acctuniqueid` varchar(32) COLLATE utf8_unicode_ci NOT NULL DEFAULT '',
  `username` varchar(64) COLLATE utf8_unicode_ci NOT NULL DEFAULT '',
  `groupname` varchar(64) COLLATE utf8_unicode_ci NOT NULL DEFAULT '',
  `realm` varchar(64) COLLATE utf8_unicode_ci DEFAULT '',
  `nasipaddress` varchar(15) COLLATE utf8_unicode_ci NOT NULL DEFAULT '',
  `nasportid` varchar(15) COLLATE utf8_unicode_ci DEFAULT NULL,
  `nasporttype` varchar(32) COLLATE utf8_unicode_ci DEFAULT NULL,

jammaloo

# Simple version

SELECT
  username,
  max(connected),
  max(disconnected)
FROM radacct
GROUP BY username