PHP Scripting question?

[DIVAD3]

Here is the entire 3 scripts unscathed by me Mark. If you could just quote them and put in the XXX's or indicate by any terms, where I am to insert what is neccessary. I think I might crasp things a little bit better. I can't promise that however! At least that way I can just make the comparison

The Database Configuration:
<?php

// dbConfig.php is a file that contains your
// database connection information. This
// tutorial assumes a connection is made from
// this existing file.
include ("dbConfig.php");


//Input vaildation and the dbase code
if ( $_GET["op"] == "reg" )
{
$bInputFlag = false;
foreach ( $_POST as $field )
{
if ($field == "")
{
$bInputFlag = false;
}
else
{
$bInputFlag = true;
}
}
// If we had problems with the input, exit with error
if ($bInputFlag == false)
{
die( "Problem with your registration info. "
."Please go back and try again.");
}

// Fields are clear, add user to database
// Setup query
$q = "INSERT INTO `dbUsers` (`username`,`password`,`email`) "
."VALUES ('".$_POST["username"]."', "
."PASSWORD('".$_POST["password"]."'), "
."'".$_POST["email"]."')";
// Run query
$r = mysql_query($q);

// Make sure query inserted user successfully
if ( !mysql_insert_id() )
{
die("Error: User not added to database.");
}
else
{
// Redirect to thank you page.
Header("Location: register.php?op=thanks");
}
} // end if


//The thank you page
elseif ( $_GET["op"] == "thanks" )
{
echo "<h2>Thanks for registering!</h2>";
}

//The web form for input ability
else
{
echo "<form action=\"?op=reg\" method=\"POST\">\n";
echo "Username: <input name=\"username\" MAXLENGTH=\"16\"><br />\n";
echo "Password: <input type=\"password\" name=\"password\" MAXLENGTH=\"16\"><br />\n";
echo "Email Address: <input name=\"email\" MAXLENGTH=\"25\"><br />\n";
echo "<input type=\"submit\">\n";
echo "</form>\n";
}
// EOF
?>

-----------------------------------------------
THE REGISTRATION:
<?php

// dbConfig.php is a file that contains your
// database connection information. This
// tutorial assumes a connection is made from
// this existing file.
include ("dbConfig.php");


//Input vaildation and the dbase code
if ( $_GET["op"] == "reg" )
{
$bInputFlag = false;
foreach ( $_POST as $field )
{
if ($field == "")
{
$bInputFlag = false;
}
else
{
$bInputFlag = true;
}
}
// If we had problems with the input, exit with error
if ($bInputFlag == false)
{
die( "Problem with your registration info. "
."Please go back and try again.");
}

// Fields are clear, add user to database
// Setup query
$q = "INSERT INTO `dbUsers` (`username`,`password`,`email`) "
."VALUES ('".$_POST["username"]."', "
."PASSWORD('".$_POST["password"]."'), "
."'".$_POST["email"]."')";
// Run query
$r = mysql_query($q);

// Make sure query inserted user successfully
if ( !mysql_insert_id() )
{
die("Error: User not added to database.");
}
else
{
// Redirect to thank you page.
Header("Location: register.php?op=thanks");
}
} // end if


//The thank you page
elseif ( $_GET["op"] == "thanks" )
{
echo "<h2>Thanks for registering!</h2>";
}

//The web form for input ability
else
{
echo "<form action=\"?op=reg\" method=\"POST\">\n";
echo "Username: <input name=\"username\" MAXLENGTH=\"16\"><br />\n";
echo "Password: <input type=\"password\" name=\"password\" MAXLENGTH=\"16\"><br />\n";
echo "Email Address: <input name=\"email\" MAXLENGTH=\"25\"><br />\n";
echo "<input type=\"submit\">\n";
echo "</form>\n";
}
// EOF
?>

------------------------------------------------------------------------
THE LOGIN:

<?php
session_start();
// dBase file
include "dbConfig.php";

if ($_GET["op"] == "login")
{
if (!$_POST["username"] || !$_POST["password"])
{
die("You need to provide a username and password.");
}

// Create query
$q = "SELECT * FROM `dbUsers` "
."WHERE `username`='".$_POST["username"]."' "
."AND `password`=PASSWORD('".$_POST["password"]."') "
."LIMIT 1";
// Run query
$r = mysql_query($q);

if ( $obj = @mysql_fetch_object($r) )
{
// Login good, create session variables
$_SESSION["valid_id"] = $obj->id;
$_SESSION["valid_user"] = $_POST["username"];
$_SESSION["valid_time"] = time();

// Redirect to member page
Header("Location: members.php");
}
else
{
// Login not successful
die("Sorry, could not log you in. Wrong login information.");
}
}
else
{
//If all went right the Web form appears and users can log in
echo "<form action=\"?op=login\" method=\"POST\">";
echo "Username: <input name=\"username\" size=\"15\"><br />";
echo "Password: <input type=\"password\" name=\"password\" size=\"8\"><br />";
echo "<input type=\"submit\" value=\"Login\">";
echo "</form>";
}
?>