현재 접속자에 대한 질문

tail.sub.php에서 보면 아래와 같이&amp;nbsp; 있는데&amp;nbsp; <br />
//-----------------------------------<br />
<br />
$tmp_sql = &quot; select count(*) as cnt from $g4[login_table] where lo_ip = &#039;$_SERVER[REMOTE_ADDR]&#039; &quot;;<br />
$tmp_row = sql_fetch($tmp_sql);<br />
//sql_query(&quot; lock table $g4[login_table] write &quot;, false);<br />
if ($tmp_row[&#039;cnt&#039;])<br />
{<br />
$tmp_sql = &quot; update $g4[login_table] set mb_id = &#039;$member[mb_id]&#039;, lo_datetime = &#039;$g4[time_ymdhis]&#039;, lo_location = &#039;$lo_location&#039;, lo_url = &#039;$lo_url&#039; where lo_ip = &#039;$_SERVER[REMOTE_ADDR]&#039; &quot;;<br />
sql_query($tmp_sql, FALSE);<br />
}<br />
else<br />
{<br />
$tmp_sql = &quot; insert into $g4[login_table] ( lo_ip, mb_id, lo_datetime, lo_location, lo_url ) values ( &#039;$_SERVER[REMOTE_ADDR]&#039;, &#039;$member[mb_id]&#039;, &#039;$g4[time_ymdhis]&#039;, &#039;$lo_location&#039;,&amp;nbsp; &#039;$lo_url&#039; ) &quot;;<br />
sql_query($tmp_sql, FALSE);<br />
<br />
// 시간이 지난 접속은 삭제한다<br />
sql_query(&quot; delete from $g4[login_table] where lo_datetime &lt; &#039;&quot;.date(&quot;Y-m-d H:i:s&quot;, $g4[server_time] - (60 * $config[cf_login_minutes])).&quot;&#039; &quot;);<br />
<br />
// 부담(overhead)이 있다면 테이블 최적화<br />
//$row = sql_fetch(&quot; SHOW TABLE STATUS FROM `$mysql_db` LIKE &#039;$g4[login_table]&#039; &quot;);<br />
//if ($row[&#039;Data_free&#039;] &gt; 0) sql_query(&quot; OPTIMIZE TABLE $g4[login_table] &quot;);<br />
}<br />
//-----------------------------------------------<br />
<br />
db에 현재 접속한 ip가 있을때에는&amp;nbsp; 그저&amp;nbsp; 업데이트만&amp;nbsp; 해주었는데&amp;nbsp; <br />
<br />
왜 db에 현재 접속한 ip가&amp;nbsp; 없을때처럼 시간이&amp;nbsp; 지난 접속은&amp;nbsp; 삭제를 안&amp;nbsp; 하는거죠?