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<html>
<body>
 <?php session_start();?>// session for this user has been started
 <?php
$con = oci_connect("SYSTEM", "123456", "localhost:1521/ORCL");//connection string
if (!$con) {
$m = oci_error();
echo $m['message'], "\n";
//error fuction returns an oracle message.
exit;
$query = "SELECT ID  FROM LOGIN WHERE USERNAME =: and PASSWORD=:PASSWORD";
//query is sent to the db to fetch row id.
 $stid = oci_parse($con, $query);
/*oci_parse fuction prepares the db to execute the statement.
requires two parameters resource($con)and sql string.*/
if (isset($_POST['USERNAME']) ||isset($_POST['PASSWORD'])){
$USERNAME = $_POST['USERNAME'];
$PASSWORD=$_POST['PASSWORD'];

}
oci_bind_by_name($stid, ':USERNAME', $user);
oci_bind_by_name($stid, ':PASSWORD', $name);

oci_execute($stid);
$row = oci_fetch_array($stid, OCI_ASSOC);
//oci_fetch_array returns a row from the db.

 if ($row) {
 $_SESSION['USERNAME']=$_POST['USERNAME'];
 echo"log in successful";
  }
 else {
echo("The person " . $name . " is not found .
Please check the spelling and try again or check password");
exit;
}
$USERNAME = $row['USERNAME'];
oci_free_statement($stid);
oci_close($con);
header('Location: wel.php');
//header function locates you to a welcome page saved s wel.php
 ?>
 </body>
 </html>