Query takes long time

[sandy1028]

Please help me

 

$result = mysql_query("select jobid,unix_timestamp(subtime)) from `completedtable`");
                $no_of_rows = mysql_num_rows($result);
        while($r = mysql_fetch_array($result)){
                $exec = '';
                $res = mysql_query("select distinct(exec) from `exectable` where jobid='".$r[0]."'");
                //$res=mysql_query($res1);
                while($row = mysql_fetch_array($res)){
                   $exec .= $row[0]."\n";
                }

 

The field exec has more than 3 rows so I have used it in while loop. Which takes lots of time to query.

How can I make a query faster.

Two tables has jobid has common field name.

 

[fenway]

Well, you can easily join the tables on jobid and group by exec.

[sandy1028]

select com.*,exc.exec from completedtable com, exectable where  com.jobid=exc.jobid group by exc.exec;

 

This query doesnot work in mysql database.

It doesnot execute even after ten mnutes

[fenway]

Then you're missing indexes... let's see the EXPLAIN output.