How can I update a field in a MySQL database table by addition in MySQL database in a single query

Question

I have a table that stores a value that will be added to over time. When I want to add to the value I would like to do so in a single query rather than -

1. Get oldValue from database
2. newValue = oldValue + X

3. update row with newValue

   $query1 = "SELECT value FROM table WHERE id = thisID"; $result1 = mysql_query($query1); while($row=mysql_fetch_array($result)) { $oldValue = $row['value']; } $newValue = $oldValue + x $query1 = "UPDATE table SET value = $newValue WHERE id = thisID";

Can this be done in a single query?

Answer 1

UPDATE table SET value = value + x WHERE id = thisID

Answer 2

UPDATE table SET field = oldValue + X WHERE id = 1