PHP Select from multiple tables and add value together to get total - php

Question

i am trying to run these queries in PHP to a mysql table
$sql="SELECT * from customer where customerid > '' and voicemail_max > '' and company_status = '' ";
$rs=mysql_query($sql,$conn);
while($customer=mysql_fetch_array($rs)) {
$sql2="SELECT * from client where parent_client_id = '".$customer["customerid"]."' ";
$rs2=mysql_query($sql2,$pbx01_conn);
while($result2=mysql_fetch_array($rs2))
{
$sql3="SELECT * from extension where client_id = '".substr($result2["id"],1,3)."' ";
$rs3=mysql_query($sql3,$pbx01_conn);
while($result3=mysql_fetch_array($rs3))
{
$sql4="SELECT * from extension_voicemail where extension_id = '".$result3["id"]."' ";
$rs4=mysql_query($sql4,$pbx01_conn);
$voicemail_size_total=0;
while($result4=mysql_fetch_array($rs4)) {
$voicemail_size_total = $voicemail_size_total+$result4["filesize"];
}
}
}
echo $voicemail_size_total;
}
it should be adding up multiple values from one column
the $sql4 query looks like:
SELECT * from extension_voicemail where extension_id = '1454'
and when i run that in the database, it returns one row with the file size column as 31780
but when i echo $voicemail_size_total variable, it shows nothing.
it works fine if i echo that variable one line up from where it is, but where it is now shows nothing

Answer 1

Declare $voicemail_size_total=0; outside of all of the while loops. Everytime you get back to the loop you re-set that back to 0. That might be the problem.

Answer 2

Well, it depends on what you want to achieve:
1. If you want to get a total of all the filesizes (basicly you are expecting just one value to be presented ) try this:
$sql="SELECT * from customer where customerid > '' and voicemail_max > '' and company_status = '' ";
$rs=mysql_query($sql,$conn);
$voicemail_size_total=0;
while($customer=mysql_fetch_array($rs)) {
$sql2="SELECT * from client where parent_client_id = '".$customer["customerid"]."' ";
$rs2=mysql_query($sql2,$pbx01_conn);
while($result2=mysql_fetch_array($rs2))
{
$sql3="SELECT * from extension where client_id = '".substr($result2["id"],1,3)."' ";
$rs3=mysql_query($sql3,$pbx01_conn);
while($result3=mysql_fetch_array($rs3))
{
$sql4="SELECT * from extension_voicemail where extension_id = '".$result3["id"]."' ";
$rs4=mysql_query($sql4,$pbx01_conn);
while($result4=mysql_fetch_array($rs4)) {
$voicemail_size_total = $voicemail_size_total+$result4["filesize"];
}
}
}
}
echo $voicemail_size_total;
2. If you're looking for the filesizes of each client (ie. expecting a series of filesizes to be presented ) try this:
$sql="SELECT * from customer where customerid > '' and voicemail_max > '' and company_status = '' ";
$rs=mysql_query($sql,$conn);
while($customer=mysql_fetch_array($rs)) {
$sql2="SELECT * from client where parent_client_id = '".$customer["customerid"]."' ";
$rs2=mysql_query($sql2,$pbx01_conn);
$voicemail_size_total=0;
while($result2=mysql_fetch_array($rs2))
{
$sql3="SELECT * from extension where client_id = '".substr($result2["id"],1,3)."' ";
$rs3=mysql_query($sql3,$pbx01_conn);
while($result3=mysql_fetch_array($rs3))
{
$sql4="SELECT * from extension_voicemail where extension_id = '".$result3["id"]."' ";
$rs4=mysql_query($sql4,$pbx01_conn);
while($result4=mysql_fetch_array($rs4)) {
$voicemail_size_total = $voicemail_size_total+$result4["filesize"];
}
}
}
echo $voicemail_size_total;
}