This is a module for MySQL Bot Core system.
You'll need http://www.hawkee.com/snippet/8882/ in case for this to work.

[12:02] !seen wubwubwub
[12:02] -#DEV-SQL- Last seen wubwubwub before 34secs changing nickname to Hawkee

MySQL Database Structure:

CREATE TABLE `seen` (
  `nickname` varchar(50) NOT NULL,
  `address` varchar(200) NOT NULL,
  `time` datetime NOT NULL,
  `network` varchar(50) NOT NULL,
  `action` enum('j','p','q','n','a','t') NOT NULL,
  `extra` varchar(100) NOT NULL,
  PRIMARY KEY (`nickname`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1;

CHANGELOG:
1.00 STABLE -> 1.01 STABLE

• Removed $iif statement on result return, didn't return action if no %extra variable.
• Updated $m.dbres variable with extra network checking according to MBC version 1.02 (still works with 1.01 though)
  1.00 STABLE -> 1.02 STABLE
• Implemented communication with core system according to MBC version 1.12 (must update core, if updating module)
  1.02 STABLE -> 1.14 STABLE
• Implemented caching, now safe for remote MySQL server users.
• Added fourth parameter to the m.modules, that will be used in next base version.
• Added nick changing to m.seen.action.
• Changed return value for the result.
  1.14 STABLE -> 1.15 STABLE
• Added checking whether extra parameter exists before trying to write it in cache database.

; MySQL Bot Core
; Module: Seen System
; Version: 1.15 STABLE
; Author: Nils Putnins (Neisen@Neisen.lv)

; - aliases
alias -l m.seen.db return $qt($mircdirseen.mbc.ini)
alias -l m.seenres return $iif($readini($m.seen.db,$1,$2),$v1,$m.dbres($2,seen,nickname,$1))
alias -l m.seen {
  if (!$isid && $3) {
    writeini -n $m.seen.db $1 address $2
    writeini -n $m.seen.db $1 time $ctime
    writeini -n $m.seen.db $1 network $network
    writeini -n $m.seen.db $1 action $left($3, 1)
    $iif($4,writeini -n $m.seen.db $1 extra $v1)
  }
  else if ($prop == sync) {
    var %records = $ini($m.seen.db,0), %sql = REPLACE INTO `seen` (`nickname`,`address`,`time`,`network`,`action`,`extra`) VALUES (?, ?, ?, ?, ?, ?)
    while %records {
      var %target = $ini($m.seen.db,%records)
      noop $mysql_query(%m.sql, %sql, %target, $m.seenres(%target,address), $asctime($m.seenres(%target,time),yyyy-mm-dd HH:nn:ss), $m.seenres(%target,network), $m.seenres(%target,action), $m.seenres(%target,extra))
      dec %records
    }
    .remove $m.seen.db
  }
  else if ($1) {
    if ($1 == $me) return Uhm...?
    else if ($1 == $nick) return Ehm...?
    else if ($1 ison $2) return Erhm..?
    var %result = $iif($m.seenres($1,time) !isnum,$ctime($v1),$v1)
    $iif(!%result,return No seen results for this nickname.)
    return Last seen $bold($1) before $duration($calc($ctime - %result),2) $m.seen.action($m.seenres($1,action)) $m.seenres($1,extra)
  }
}

alias -l m.seen.action {
  if ($1 = t) return saying something on
  else if ($1 = a) return making action in
  else if ($1 = q) return quitting
  else if ($1 = j) return joining
  else if ($1 = p) return parting
  else if ($1 = n) return changing nickname to
}

; - actions
on *:JOIN:#:m.seen $nick $fulladdress join $chan
on *:PART:#:m.seen $nick $fulladdress part $chan
on *:QUIT:m.seen $nick $fulladdress quit
on *:NICK:m.seen $nick $fulladdress nick $newnick
on *:ACTION:*:#:m.seen $nick $fulladdress action $chan
on *:TEXT:*:*:{
  if ($chan) m.seen $nick $fulladdress text $chan
  if ($1 == $command(seen)) $iif($chan,notice,msg) $nick $m.seen($2,$chan)
}

; - communicating with core
on *:SIGNAL:m.modules:{
  m.modules $+(Seen System,$chr(124),$command(seen),$chr(124),0,$chr(124),$remove($script,$mircdir))
  noop $m.seen().sync
}