Working with PHP Echos and mySQL Count queries amongst others - php

Question

Just so you have some idea of my system, I have a PASSENGER table that has all the passenger's personal details in (you know surname, first name etc). But it also stores a 'username' and 'groupID' field. The username allows the passenger's details to be linked to the currently logged in user through:-
$loggedinuser = $session->username;
However, all those passengers who belong to one family (or who have booked together) are linked by a GROUP ID. What I would like to do is find out how many people are in a certain group...the group in question being the one linked to the current user!
For example a COUNT mySQL query on the groupID where the groupID = the group ID of the currently logged in user.
This value will then go in a HTML form.
<?php
$loggedinuser = $session->username;
$sql="SELECT count(p.groupID) AS count FROM PASSENGER p WHERE p.username = '$loggedinuser'";
$rows = mysql_num_rows($sql);
{
echo 'Number of Passengers: <input type="text" name="groupno" value = "'.$rows['groupID']. "\" /><br />";
Which is the first part of the code....
I appear to be able to find out the groupID of the currently logged in user through this code:-
$query3 = "SELECT p.groupID FROM PASSENGER p f WHERE p.username = '$loggedinuser'";
$result = mysql_query($query3);
while($row = mysql_fetch_array($result))
{
echo $row['groupID'];
}
}}
echo mysql_error();
But am I able to store the value that is echoed here:-
echo $row['groupID'];
As a variable for example?
AS then, when I want to return all of the similar users in the group (linked by GroupID), I would then have a variable to use, rather than
$sql='SELECT * FROM PASSENGER WHERE groupID="5"';
$query=mysql_query($sql);
$count=mysql_num_rows($query);
while($fetch_arr=mysql_fetch_array($query)){
$familyName=$fetch_arr['surname'];
echo $familyName;
As the first line of the mySQL query would read something along the lines of:-
$sql='SELECT * FROM PASSENGER WHERE groupID='$loggedingroupID'";
I appreciate any help, if you have any questions just comment and I'll be glad to clarify what I mean!
Regards,
Tom
EDIT: Session Class
<?
/**
* Session.php
*
* The Session class is meant to simplify the task of keeping
* track of logged in users and also guests.
*
* Please subscribe to our feeds
*/
include("database.php");
include("mailer.php");
include("form.php");
class Session
{
var $username; //Username given on sign-up
var $userid; //Random value generated on current login
var $userlevel; //The level to which the user pertains
var $time; //Time user was last active (page loaded)
var $logged_in; //True if user is logged in, false otherwise
var $userinfo = array(); //The array holding all user info
var $url; //The page url current being viewed
var $referrer; //Last recorded site page viewed
/**
* Note: referrer should really only be considered the actual
* page referrer in process.php, any other time it may be
* inaccurate.
*/
/* Class constructor */
function Session() {
$this->time = time();
$this->startSession();
}
/**
* startSession - Performs all the actions necessary to
* initialize this session object. Tries to determine if the
* the user has logged in already, and sets the variables
* accordingly. Also takes advantage of this page load to
* update the active visitors tables.
*/
function startSession(){
global $database; //The database connection
session_start(); //Tell PHP to start the session
/* Determine if user is logged in */
$this->logged_in = $this->checkLogin();
/**
* Set guest value to users not logged in, and update
* active guests table accordingly.
*/
if(!$this->logged_in){
$this->username = $_SESSION['username'] = GUEST_NAME;
$this->userlevel = GUEST_LEVEL;
$database->addActiveGuest($_SERVER['REMOTE_ADDR'], $this->time);
}
/* Update users last active timestamp */
else{
$database->addActiveUser($this->username, $this->time);
}
/* Remove inactive visitors from database */
$database->removeInactiveUsers();
$database->removeInactiveGuests();
/* Set referrer page */
if(isset($_SESSION['url'])){
$this->referrer = $_SESSION['url'];
}else{
$this->referrer = "/";
}
/* Set current url */
$this->url = $_SESSION['url'] = $_SERVER['PHP_SELF'];
}
/**
* checkLogin - Checks if the user has already previously
* logged in, and a session with the user has already been
* established. Also checks to see if user has been remembered.
* If so, the database is queried to make sure of the user's
* authenticity. Returns true if the user has logged in.
*/
function checkLogin(){
global $database; //The database connection
/* Check if user has been remembered */
if(isset($_COOKIE['cookname']) && isset($_COOKIE['cookid'])){
$this->username = $_SESSION['username'] = $_COOKIE['cookname'];
$this->userid = $_SESSION['userid'] = $_COOKIE['cookid'];
}
/* Username and userid have been set and not guest */
if(isset($_SESSION['username']) && isset($_SESSION['userid']) &&
$_SESSION['username'] != GUEST_NAME){
/* Confirm that username and userid are valid */
if($database->confirmUserID($_SESSION['username'], $_SESSION['userid']) != 0){
/* Variables are incorrect, user not logged in */
unset($_SESSION['username']);
unset($_SESSION['userid']);
return false;
}
/* User is logged in, set class variables */
$this->userinfo = $database->getUserInfo($_SESSION['username']);
$this->username = $this->userinfo['username'];
$this->userid = $this->userinfo['userid'];
$this->userlevel = $this->userinfo['userlevel'];
return true;
}
/* User not logged in */
else{
return false;
}
}
/**
* login - The user has submitted his username and password
* through the login form, this function checks the authenticity
* of that information in the database and creates the session.
* Effectively logging in the user if all goes well.
*/
function login($subuser, $subpass, $subremember){
global $database, $form; //The database and form object
/* Username error checking */
$field = "user"; //Use field name for username
if(!$subuser || strlen($subuser = trim($subuser)) == 0){
$form->setError($field, "* Username not entered");
}
else{
/* Check if username is not alphanumeric */
if(!eregi("^([0-9a-z])*$", $subuser)){
$form->setError($field, "* Username not alphanumeric");
}
}
/* Password error checking */
$field = "pass"; //Use field name for password
if(!$subpass){
$form->setError($field, "* Password not entered");
}
/* Return if form errors exist */
if($form->num_errors > 0){
return false;
}
/* Checks that username is in database and password is correct */
$subuser = stripslashes($subuser);
$result = $database->confirmUserPass($subuser, md5($subpass));
/* Check error codes */
if($result == 1){
$field = "user";
$form->setError($field, "* Username not found");
}
else if($result == 2){
$field = "pass";
$form->setError($field, "* Invalid password");
}
/* Return if form errors exist */
if($form->num_errors > 0){
return false;
}
/* Username and password correct, register session variables */
$this->userinfo = $database->getUserInfo($subuser);
$this->username = $_SESSION['username'] = $this->userinfo['username'];
$this->userid = $_SESSION['userid'] = $this->generateRandID();
$this->userlevel = $this->userinfo['userlevel'];
/* Insert userid into database and update active users table */
$database->updateUserField($this->username, "userid", $this->userid);
$database->addActiveUser($this->username, $this->time);
$database->removeActiveGuest($_SERVER['REMOTE_ADDR']);
/**
* This is the cool part: the user has requested that we remember that
* he's logged in, so we set two cookies. One to hold his username,
* and one to hold his random value userid. It expires by the time
* specified in constants.php. Now, next time he comes to our site, we will
* log him in automatically, but only if he didn't log out before he left.
*/
if($subremember){
setcookie("cookname", $this->username, time()+COOKIE_EXPIRE, COOKIE_PATH);
setcookie("cookid", $this->userid, time()+COOKIE_EXPIRE, COOKIE_PATH);
}
/* Login completed successfully */
return true;
}
/**
* logout - Gets called when the user wants to be logged out of the
* website. It deletes any cookies that were stored on the users
* computer as a result of him wanting to be remembered, and also
* unsets session variables and demotes his user level to guest.
*/
function logout(){
global $database; //The database connection
/**
* Delete cookies - the time must be in the past,
* so just negate what you added when creating the
* cookie.
*/
if(isset($_COOKIE['cookname']) && isset($_COOKIE['cookid'])){
setcookie("cookname", "", time()-COOKIE_EXPIRE, COOKIE_PATH);
setcookie("cookid", "", time()-COOKIE_EXPIRE, COOKIE_PATH);
}
/* Unset PHP session variables */
unset($_SESSION['username']);
unset($_SESSION['userid']);
/* Reflect fact that user has logged out */
$this->logged_in = false;
/**
* Remove from active users table and add to
* active guests tables.
*/
$database->removeActiveUser($this->username);
$database->addActiveGuest($_SERVER['REMOTE_ADDR'], $this->time);
/* Set user level to guest */
$this->username = GUEST_NAME;
$this->userlevel = GUEST_LEVEL;
}
/**
* register - Gets called when the user has just submitted the
* registration form. Determines if there were any errors with
* the entry fields, if so, it records the errors and returns
* 1. If no errors were found, it registers the new user and
* returns 0. Returns 2 if registration failed.
*/
function register($subuser, $subpass, $subemail){
global $database, $form, $mailer; //The database, form and mailer object
/* Username error checking */
$field = "user"; //Use field name for username
if(!$subuser || strlen($subuser = trim($subuser)) == 0){
$form->setError($field, "* Username not entered");
}
else{
/* Spruce up username, check length */
$subuser = stripslashes($subuser);
if(strlen($subuser) < 5){
$form->setError($field, "* Username below 5 characters");
}
else if(strlen($subuser) > 30){
$form->setError($field, "* Username above 30 characters");
}
/* Check if username is not alphanumeric */
else if(!eregi("^([0-9a-z])+$", $subuser)){
$form->setError($field, "* Username not alphanumeric");
}
/* Check if username is reserved */
else if(strcasecmp($subuser, GUEST_NAME) == 0){
$form->setError($field, "* Username reserved word");
}
/* Check if username is already in use */
else if($database->usernameTaken($subuser)){
$form->setError($field, "* Username already in use");
}
/* Check if username is banned */
else if($database->usernameBanned($subuser)){
$form->setError($field, "* Username banned");
}
}
/* Password error checking */
$field = "pass"; //Use field name for password
if(!$subpass){
$form->setError($field, "* Password not entered");
}
else{
/* Spruce up password and check length*/
$subpass = stripslashes($subpass);
if(strlen($subpass) < 4){
$form->setError($field, "* Password too short");
}
/* Check if password is not alphanumeric */
else if(!eregi("^([0-9a-z])+$", ($subpass = trim($subpass)))){
$form->setError($field, "* Password not alphanumeric");
}
/**
* Note: I trimmed the password only after I checked the length
* because if you fill the password field up with spaces
* it looks like a lot more characters than 4, so it looks
* kind of stupid to report "password too short".
*/
}
/* Email error checking */
$field = "email"; //Use field name for email
if(!$subemail || strlen($subemail = trim($subemail)) == 0){
$form->setError($field, "* Email not entered");
}
else{
/* Check if valid email address */
$regex = "^[_+a-z0-9-]+(\.[_+a-z0-9-]+)*"
."#[a-z0-9-]+(\.[a-z0-9-]{1,})*"
."\.([a-z]{2,}){1}$";
if(!eregi($regex,$subemail)){
$form->setError($field, "* Email invalid");
}
$subemail = stripslashes($subemail);
}
/* Errors exist, have user correct them */
if($form->num_errors > 0){
return 1; //Errors with form
}
/* No errors, add the new account to the */
else{
if($database->addNewUser($subuser, md5($subpass), $subemail)){
if(EMAIL_WELCOME){
$mailer->sendWelcome($subuser,$subemail,$subpass);
}
return 0; //New user added succesfully
}else{
return 2; //Registration attempt failed
}
}
}
/**
* editAccount - Attempts to edit the user's account information
* including the password, which it first makes sure is correct
* if entered, if so and the new password is in the right
* format, the change is made. All other fields are changed
* automatically.
*/
function editAccount($subcurpass, $subnewpass, $subemail){
global $database, $form; //The database and form object
/* New password entered */
if($subnewpass){
/* Current Password error checking */
$field = "curpass"; //Use field name for current password
if(!$subcurpass){
$form->setError($field, "* Current Password not entered");
}
else{
/* Check if password too short or is not alphanumeric */
$subcurpass = stripslashes($subcurpass);
if(strlen($subcurpass) < 4 ||
!eregi("^([0-9a-z])+$", ($subcurpass = trim($subcurpass)))){
$form->setError($field, "* Current Password incorrect");
}
/* Password entered is incorrect */
if($database->confirmUserPass($this->username,md5($subcurpass)) != 0){
$form->setError($field, "* Current Password incorrect");
}
}
/* New Password error checking */
$field = "newpass"; //Use field name for new password
/* Spruce up password and check length*/
$subpass = stripslashes($subnewpass);
if(strlen($subnewpass) < 4){
$form->setError($field, "* New Password too short");
}
/* Check if password is not alphanumeric */
else if(!eregi("^([0-9a-z])+$", ($subnewpass = trim($subnewpass)))){
$form->setError($field, "* New Password not alphanumeric");
}
}
/* Change password attempted */
else if($subcurpass){
/* New Password error reporting */
$field = "newpass"; //Use field name for new password
$form->setError($field, "* New Password not entered");
}
/* Email error checking */
$field = "email"; //Use field name for email
if($subemail && strlen($subemail = trim($subemail)) > 0){
/* Check if valid email address */
$regex = "^[_+a-z0-9-]+(\.[_+a-z0-9-]+)*"
."#[a-z0-9-]+(\.[a-z0-9-]{1,})*"
."\.([a-z]{2,}){1}$";
if(!eregi($regex,$subemail)){
$form->setError($field, "* Email invalid");
}
$subemail = stripslashes($subemail);
}
/* Errors exist, have user correct them */
if($form->num_errors > 0){
return false; //Errors with form
}
/* Update password since there were no errors */
if($subcurpass && $subnewpass){
$database->updateUserField($this->username,"password",md5($subnewpass));
}
/* Change Email */
if($subemail){
$database->updateUserField($this->username,"email",$subemail);
}
/* Success! */
return true;
}
/**
* isAdmin - Returns true if currently logged in user is
* an administrator, false otherwise.
*/
function isAdmin(){
return ($this->userlevel == ADMIN_LEVEL ||
$this->username == ADMIN_NAME);
}
/**
* generateRandID - Generates a string made up of randomized
* letters (lower and upper case) and digits and returns
* the md5 hash of it to be used as a userid.
*/
function generateRandID(){
return md5($this->generateRandStr(16));
}
/**
* generateRandStr - Generates a string made up of randomized
* letters (lower and upper case) and digits, the length
* is a specified parameter.
*/
function generateRandStr($length){
$randstr = "";
for($i=0; $i<$length; $i++){
$randnum = mt_rand(0,61);
if($randnum < 10){
$randstr .= chr($randnum+48);
}else if($randnum < 36){
$randstr .= chr($randnum+55);
}else{
$randstr .= chr($randnum+61);
}
}
return $randstr;
}
};
/**
* Initialize session object - This must be initialized before
* the form object because the form uses session variables,
* which cannot be accessed unless the session has started.
*/
$session = new Session;
/* Initialize form object */
$form = new Form;
?>

Answer 1

anyway. what you could do as well is:
$query3 = "SELECT p.groupID FROM PASSENGER p f WHERE p.username = '$loggedinuser'";
$result = mysql_query($query3);
while($row = mysql_fetch_array($result))
{
$_SESSION['groupID'] = $row['groupID'];
}
echo mysql_error();
then you call it anywhere:
$groupID= $_SESSION['groupID'];
got to run now. if you have problem with above solution, let me know i'll be back in an hour or so, ok?

Answer 2

if i understand rigth you are initially displaying the gruop of the logged user in an html page.
Now when the php script finishes its execution and the html is displayed every variable you set in the script is gone.
When you have another interaction with the same or others php scripts previuos previous script execution variables are not available.
So to reach what you want 2 solutions:
Save the gruop id in session: $_SESSION["gruop"] = $row['groupID'];
Then others php page you call will be able to retreive the gruop and display for example the list of users that share that groupid
Or in the html you display insert an link that point to a page and send it as parameter the group id: href="display_users_by_group.php?gruopid=".$row['groupID']. When you click the link the page display_users_by_group.php can retreive the groupid with $_GET["groupid"]

Answer 3

Do you mean this?
SELECT groupID, COUNT(*) FROM PASSENGER GROUP BY groupID
This will give you groupId and number of people which are in it ...
$sql=mysql_query(SELECT groupID, COUNT(*) as c FROM PASSENGER GROUP BY groupID);
if(mysql_num_rows($sql)>0) while($entry=mysql_fetch_array($sql)) {
$group=$entry['groupId'];
$count=$entry['c'];
$sql2=mysql_query("SELECT user.name FROM PASSENGER WHERE groupID='.$group.'");
if(mysql_num_rows($sql2)>0) while($entry2=mysql_fetch_array($sql2)) {
$user=$entry2['user'];
}
}
Here you have this query and subquery, when you can get list of users in each group.