Hello guys!

I have one problem.
On MySQL database I have table with name 'all_visitors' and there I have two column...
id Visitors
1 5690
2 5434
3 234
... ...
x 45455
y 45858

How can I sum last five Visitors?

I use...

PHP Code:

$sql = "SELECT SUM(Visitors) FROM all_visitors ORDER BY id DESC LIMIT 5";

$result_query = mysql_query($sql);
$result = mysql_fetch_array($result_query);
$sum_five_visitors = $result[0];

echo ''.$sum_five_visitors.''; 


...but this function sum all Visitors.

Thank you 4 answer ... and sorry 4 my bad english.

SELECT SUM(visitors) FROM all_visitors WHERE id >= (SELECT id from all_visitors ORDER BY id DESC limit 5,1)

As far as I know, you need a WHERE clause to narrow down the results for the SUM to work. The subquery grabs the fifth-to-last ID in the table, and the main query only show results greater than or equal to that ID.

A GROUP BY clause would probably narrow it down for you too, but I couldn't think of a good way to fit that in in this instance.

You could also just grab the last 5 entries without using SUM, and use a PHP loop to add them up.