Change values around in mysql database using php - php

Question

I have the code below:
$do_id=$_GET['id'];
$new_workorder=$_GET['workorder'];
//get current workorder on file for record that will be updated
$query = "SELECT workorder FROM jvltodos WHERE id = '$do_id' LIMIT 1";
$bla = mysql_query($query);
$workorder_old = mysql_fetch_row($bla);
//get record for workorder on file that will have the new workorder
$query = "SELECT id FROM jvltodos WHERE workorder = '$new_workorder' LIMIT 1";
$bla = mysql_query($query);
$id_fix = mysql_fetch_row($bla);
if (isset($new_workorder) && $new_workorder!=$workorder_old) {
//update the changed record
$query = "UPDATE jvltodos
SET workorder={$new_workorder}
WHERE id = {$do_id}";
$result = mysql_query($query);
//update the record that had the old workorder
$query = "UPDATE jvltodos
SET workorder={$workorder_old}
WHERE id = {$id_fix}";
$result = mysql_query($query);
}
I pass the 'id' and 'workorder' into the url, so I GET them first. With that I update the record with that 'id' to the new 'workorder'. So far so good.
But I want to find the record that has that 'workorder' and update that with the 'workorder' from the old 'id'. (In simple terms: when I increase/decrease the 'workorder', I want to switch two records around)
To me it looks pretty straightforward, but it doesn't work. The first thing (update the id with the new workorder works.. but the other record stays the same.. it keeps the workorder that was already in there)
What am I missing? (must be something simple that I'm just overlooking.)

Answer 1

#andrewsi Thank you for the suggestion! I took the code out, copied it over to another page and did some echo's to see what was going on and that way I figured out easily what the problem was.
Example:
$bla = mysql_query($query);
$workorder_old = mysql_fetch_row($bla);
The $workorder_old that I wanted to have should've been a number. However, this didn't happen, but returned.. an array.
When I changed the code to...
$bla = mysql_query($query);
$bla = mysql_fetch_row($bla);
$workorder_old = $bla[0];
... it worked like a charm.
tiny note: I'm so used to grabbing the data in 1 step (another language), that I forgot that I needed to make a few steps in PHP. Guess it's time to throw it in a function perhaps.. :-)