Value of variable changes in while-loop - php

Question

Me and all my live contact are stunned by phenomenom where a variable value changes in other side ow while. Before 2nd loop value is correct, but inside 2nd loop value is incorrect.
Here's the actual code.
try {
$yhteys = new PDO('mysql:host=localhost;dbname=XXXX', 'YYYY', 'ZZZZ');
} catch (PDOException $e) {
die("VIRHE: " . $e->getMessage());
}
$yhteys->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
$yhteys->exec("SET NAMES utf8");
$kysely = $yhteys->prepare('SELECT viite FROM hakija WHERE vaihe = 1 ');
$kysely->execute();
$file = fopen("tilit.csv","r");
while(! feof($file)) {
$tilirivi=fgetcsv($file,100,";");
if ($tilirivi[4] < 0) continue;
$viiteviesti = substr($tilirivi[3], 1);
//print "Viiteviesti1: $viiteviesti\n"; produces correct print
while ($rivi = $kysely->fetch()) {
//print "Viiteviesti2: $viiteviesti\n"; produces incorrect print
$kantaviite=$rivi["viite"];
if ($viiteviesti == $kantaviite ) {
$asetus = $yhteys->prepare("UPDATE hakija SET vaihe=2 WHERE viite='$viiteviesti' ");
$asetus->execute();
}
}
}
How is this possible and how should I correct my code?

Answer 1

'column' is a reserved variable name according to this article:
http://hockinson.com/programmer-web-designer-denver-co-usa.php?s=43
which might cause unexpected results.

Answer 2

It came up that for some reason $kysely-fecth() didn't return any content. I got the code working and here's solution:
try {
$yhteys = new PDO('mysql:host=localhost;dbname=XXXX', 'YYYY', 'ZZZZ');
} catch (PDOException $e) {
die("VIRHE: " . $e->getMessage());
}
$yhteys->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
$yhteys->exec("SET NAMES utf8");
$kysely = $yhteys->prepare('SELECT viite FROM hakija WHERE vaihe = 1 ');
$kysely->execute();
$kysely->setFetchMode(PDO::FETCH_NUM);
$result = $kysely->fetchAll();
$file = fopen("tilit.csv","r");
while(! feof($file)) {
$tilirivi=fgetcsv($file,100,";");
if ($tilirivi[4] < 10) continue;
$viiteviesti = substr($tilirivi[3], 1);
foreach ($result as $rivi) {
foreach ($rivi as $kantaviite) {
if ($viiteviesti == $kantaviite ) {
$asetus = $yhteys->prepare("UPDATE hakija SET vaihe=2 WHERE viite='$viiteviesti' ");
$asetus->execute();
}
}
}
}