Query Improvement mysql - php

Question

Hi Guys i have this query and it is super slow.
If you can understand the code how can i possibly combine the two queries into one
or how can i possibly make this query faster.
this is the code
$strSQL = "SELECT user_status_history.*, queues_config.extension FROM user_status_history ";
$strSQL .= "LEFT JOIN queues_config ON user_status_history.skillset = REPLACE(queues_config.grppre, \":\", \"\") ";
$strSQL .= "WHERE user_status_history.status_id = 9 "; # outbound call
$strSQL .= "AND DATE_FORMAT(status_time, '%Y-%m-%d') = '$check_date' ";
if ($i==1)
$strSQL .= "AND TIME_FORMAT(status_time, '%H:%i') >= '$cboHrFrom:$cboMinFrom' ";
else if (strtotime($check_date) == strtotime($end_date))
$strSQL .= "AND TIME_FORMAT(status_time, '%H:%i') <= '$cboHrTo:$cboMinTo' ";
$strSQL .= "AND queues_config.extension = '$cboSkillSet' ";
if ($cboGroup!='' && $strAgentGroup!='') $strSQL .= "AND user_status_history.user_id IN (".$strAgentGroup.") ";
$strSQL .= "ORDER BY user_status_history.user_id, user_status_history.status_time ";
$rs2 = &$cn->Execute($strSQL);
while (!$rs2->EOF)
{
$strSQL = "SELECT status_time, time_to_sec(timediff(status_time, '".$rs2->fields['status_time']."')) AS timesecs FROM user_status_history ";
$strSQL .= "LEFT JOIN queues_config ON user_status_history.skillset = REPLACE(queues_config.grppre, \":\", \"\") ";
$strSQL .= "WHERE status_time > '".$rs2->fields['status_time']."' ";
$strSQL .= "AND user_id = '".$rs2->fields['user_id']."' ";
$strSQL .= "AND queues_config.extension = '".$rs2->fields['extension']."' ";
$strSQL .= "ORDER BY status_time LIMIT 1;";
$rs3 = &$cn->Execute($strSQL);
if (!$rs3->EOF)
{
$sum_talk_sec = $sum_talk_sec + $rs3->fields['timesecs'];
}
$rs3->Close();
$rs2->MoveNext();
}
$rs2->Close();

Answer 1

1
Check out there are table indexes for
user_status_history.status_id
user_status_history.user_id
2
these are difficult for optimizer. Try get rid of these
LEFT JOIN queues_config ON user_status_history.skillset = REPLACE(queues_config.grppre, \":\", \"\") ";
LEFT JOIN queues_config ON user_status_history.skillset = REPLACE(queues_config.grppre, \":\", \"\") ";
3
Get rid of the loop query.
Fetch all IDs from query1 to an array and create one query for them all:
"SELECT user_id, status_time, time_to_sec(timediff(status_time, '".$rs2->fields['status_time']."')) AS timesecs FROM user_status_history ";
...
AND user_id IN (id1, id2, id3 ... )
4 (From DCOder )
Convert these the other way around. Use PHP to create mysql datetime fields.
$strSQL .= "AND DATE_FORMAT(status_time, '%Y-%m-%d') = '$check_date' ";
-- >
preg_match('/^([0-9][0-9][0-9][0-9])-([0-9][0-9])-([0-9][0-9])$/', $check_date, $regs );
$enddate = date('Y-m-d', mktime( $hour=6, $min=0, $sec=0, $mon=$regs[2], $day=$regs[3]+1, $year=$regs[1] ));
$strSQL .= " AND status_time > '$check_date' AND status_time <= '$enddate' ;
$strSQL .= "AND TIME_FORMAT(status_time, '%H:%i') >= '$cboHrFrom:$cboMinFrom' ";
-- > $strSQL .= " AND status_time >= '$check_date $cboHrFrom:$cboMinFrom:00' ";
$strSQL .= "AND TIME_FORMAT(status_time, '%H:%i') <= '$cboHrTo:$cboMinTo' ";
-- > $strSQL .= " AND status_time <= '$check_date $cboHrTo:$cboMinTo:59' ";