This question already has an answer here:
If my query result is empty I want to insert information otherwise I'd like to update the information. However, I keep getting this error:
Warning: mysql_num_rows() expects parameter 1 to be resource, boolean given in...
$info = $_POST['info'];
$gebruiker = $_POST['gebruiker'];
$result = mysql_query("SELECT fysionummer FROM algemene_info WHERE = $gebruiker");
if (mysql_num_rows($result)==0) {
mysql_query("INSERT INTO algemene_info (`info_id`, `omschrijving`, `fysionummer`)
VALUES (NULL, '$info', '$gebruiker')");
//echo $response;
echo "Het toevoegen van de algemene info is geslaagd!";
} else {
mysql_query ("UPDATE algemene_info
SET omschrijving='$info'
WHERE fysionummer='$gebruiker'");
//echo $response;
echo "Het update van de algemene informatie is geslaagd!";
}
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