Delete record in database - php

Question

$qry=mysql_query("Select useradmin from tbladmin");
$credentials=mysql_fetch_array($qry);
if(!isset($_SESSION['user'])){
header("location:index.php");
exit();
}
if(isset($_REQUEST['id'])){
mysql_query("DELETE FROM tblru WHERE userid=" . $_REQUEST['id']);
if(mysql_affected_rows($con)>0){
header("location:administration.php");
exit();
}
else{
echo "ERROR in deleting the user!";
}
}
?>
this upper part is placed on top. and the lower part is in the body.
UserID
Username
Password
Add Users
<?php
$result=mysql_query("SELECT * FROM tblru");
if(mysql_num_rows($result)>0){
while($row=mysql_fetch_array($result)){
echo "<tr bgcolor='#999999'>
<td>" . $row[0] . "</td>
<td>" . $row[1] . " </td>
<td>" . $row[2] . "</td>
<td><font color='#FFFFFF'>Delete</font></td></tr>";
}
}
?>
I cant delete the users data in the database i made. the tblru has id(this is int and is auto incremented, user, and password. i would like to ask if the deletion of data is possible.

Answer 1

Your link on your code:
"</td><td><a href='admininistration.php?id=$row[0]'
Notice how you just include an array variable inside of a string? That should be...
"</td><td><a href='admininistration.php?id=".$row[0]."'
Use a proper string concatenation.
That's the reason you're not getting the right/proper value that you need.
You're getting $row[0] as the value, literally. Check your url to see.

Answer 2

Do you have an administration.php file? Is all this code in it?The errors says that the page does not exist.
This prints out just fine, it has " " not ' ' so it is seen as variable, just tested it.
$row[0] = rand(1,10);
$row[1] = rand(1,10);
$row[2] = rand(1,10);
echo "<tr bgcolor='#999999'>
<td>" . $row[0] . "</td>
<td>" . $row[1] . " </td>
<td>" . $row[2] . "</td>
<td><font color='#FFFFFF'>Delete</font></td></tr>";
Are you sure you are passing by this part?
if(!isset($_SESSION['user']))
{
header("location:index.php");
exit();
}
if you are not, you will be redirected to index.php and the rest of the script isn't going to run.
set $_SESSIONp['user'] = "something"; just before that just for test, are you getting the "ERROR in deleting the user!" when trying to delete?
Also separate the logical part from the display. and use md5() or sha1() for password encryption.
$result=mysql_query("SELECT * FROM tblru");
if(mysql_num_rows($result)>0)
{
$output = "<table>";
while($row=mysql_fetch_array($result))
{
$output .= "<tr bgcolor='#999999'>";
$output .= "<td>" . $row[0] . "</td>";
$output .= "<td>" . $row[1] . "</td>";
$output .= "<td>" . $row[2] . "</td>";
$output .= "<td><font color='#FFFFFF'>Delete</font></td></tr>";
}
$output .= "/table";
}
print_r $output;