Trouble with SUM()

[Ivains]

I am trying to add up the cost column, but having no success. Can someone tell me what I am doing wrong?

$sql = "
SELECT *, SUM(maint.cost) AS totalcost
FROM maint, lsv
WHERE maint.vid = \"$vid\"
AND maint.vid = lsv.vid
ORDER BY maint.date DESC
";

Parts of the script:

$totalcost = $row['totalcost'];

Total Spent On Maintenance: $totalcost

Thanks for all your help!

:o) Ivan

[Lars_Berg]

What's the problem?

You can't mix aggregate functions and columns like that.

$sql = " 
SELECT  SUM(maint.cost) AS totalcost 
FROM maint, lsv 
WHERE maint.vid = '$vid' 
AND maint.vid = lsv.vid 
ORDER BY maint.date DESC 
"; 

is maint.vid a numeric column? In that case you should remove the apostrophes surrounding the value.

[Ivains]

Thanks
Know of any good PHP books?