I have written a Perl script to schedule appointments at a clinic. The code puts clients in timeslots for every clinic day. There is a MySQL query that simply gets the nurse names and IDs then makes a drop-down select button beside the client's names in the schedule. When there is more than 9 people scheduled for the day the query hangs the script. It also hangs if there are more that 3 people with the same appointment time and more than 5 people in total for that day. I am completely baffled at why this script would hang under those specific circumstances, especially considering that this section of code has nothing to do with the appointment tables - it only uses the nurses table. Here is the section of code. If I comment out the stuff during the query (in the while loop) it works fine but with no nurse drop-down menu. If I do *ANYTHING* inside the while loop the code hangs. The query works fine under PHPMyAdmin. 

if ($in{clinicdate} <= $today) {
    my $query="SELECT nurseid, fname, lname FROM nurses ORDER BY fname
+ ASC;";
    my $dbh;
    my $sth;
    $dbh = DBI->connect("DBI:mysql:$dbname", $dbuser, $dbpass,{PrintEr
+ror => 1, RaiseError => 1});
    $sth=$dbh->prepare($query);
    $sth->execute();
    print "$formstart\n\t\t<INPUT TYPE=HIDDEN NAME=\"f\" VALUE=\"Chang
+eNurse\">\n\t\t\t<INPUT TYPE=HIDDEN NAME=\"clinicdate\" VALUE=\"$in{c
+linicdate}\">\n\t\t\t<INPUT TYPE=HIDDEN NAME=\"clientid\" VALUE=\"$cl
+ientid\">\n\t\t<SELECT NAME=\"nurseused\" onchange=\"this.form.submit
+()\">\n\t\t\t<OPTION VALUE=\"\">Nurse</OPTION>";
    while (@row=$sth->fetchrow()) {
        print "\n\t\t\t<OPTION VALUE=\"$row[0]\"";
        if ($nurseused{$clientid} eq $row[0]) {
            print " SELECTED";
        }
        print ">$row[1] $row[2]</OPTION>";
    }
    $sth->finish;
    $dbh->disconnect;
    print "\n\t\t\t<OPTION VALUE=\"0\" style=\"background-color:red\">
+NO SHOW!</OPTION>\n\t\t</SELECT>\n</FORM>";
} else {
    if ($confirmed{$clientid}==1) {
        print " X ";
    }
}

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In reply to perl hangs with a simple mySQL query by chuck

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