Notice: Undefined variable: led_nem in C:\xampp\htdocs\online\Online Task Management System\task_mem.php on line 71

Question

When I try to run this query

$SQL = " SELECT * FROM info WHERE username = '$led_nem'";
$result = mysql_query($SQL);
while ($db_field = mysql_fetch_assoc($result)) {
        $tsk = $db_field['group_task'];
}

I get this error

Notice: Undefined variable: led_nem in C:\xampp\htdocs\online\Online Task Management System\task_mem.php on line 71

Answer 1

Test if the variable $led_nem exists before you use it:

if (isset($led_nem)) {
    $SQL = " SELECT * FROM info WHERE username = '$led_nem'";
    $result = mysql_query($SQL);
    while ($db_field = mysql_fetch_assoc($result)) {
        $tsk = $db_field['group_task'];
    }
}

Answer 2

Use this

if (isset($led_nem)) {
$SQL = " SELECT * FROM info WHERE username = '".$led_nem."'";
$result = mysql_query($SQL);
while ($db_field = mysql_fetch_assoc($result)) {
        $tsk = $db_field['group_task'];
}
}