My questions thread.

This site is best viewed in a modern browser with JavaScript enabled.

evenstar7139

I keep having new questions so I'm starting this thread to neatly keep them all together. That's ok, I think? I hope I'm not asking too many questions :eek:

What I'm wondering right now is if I make a class--let's say User--and put it in a file--user.class.php--should any children of that class go in that file or should they have their own? Like Login could extend that class, Signup could, etc. Should they be in login.class.php and signup.class.php, respectively?

NogDog

I normally keep them in separate files. This is particularly useful if you want to use an autoload() function to take care of loading class definitions (which, however, requires a consistent naming convention so that your autoload() function can figure out where a class's file is based on the class name).

PS: I'd probably have a User class (basically a data model class) and a separate UserAuth class (basically a controller-type class) with login() and register() methods which may accept and/or return a User object as applicable (i.e., using composition instead of inheritance in this case), since log-in and register are actions, not things, so you can't really say that "Login is a User" or "Register is a User."

mistin_ca

user register, login, auth, changepass, etc.. should all be in the same class.

splitting them up has no benefit, having signup/login/register/auth etc.. classes all extending "user" just creates more overhead because in a proper system you'll have things from register, signup, login all cross referencing certain functions.

If you set it up properly ie;
$this->user->register();
$this->user->login();
$this->user->check_email();

or whatever.. you're putting everyting in the user class extending your main system core, this is what gives you the ability to add other things easily e.g.,
$this->log->insert('action','ip','date'); etc.

above your classes you can configure the autoload to do things automagically - or create an autoload function of only specifics, then each class in you're init() you'd put which extra classes you'd want to load ontop of it.

evenstar7139

I wondering why this code is only finding one row in the accounts table, in the database, when there are two. When I var_dump the results it only has the data from the first row. What could be going on?

class Database
{
    private $dbHost = 'localhost';     

    private $dbUser = 'myusername';         

    private $dbPass = 'mypassword';        

    private $dbName = 'mydatabase'; 
    private $dbConn = false;
    public $result = array();	

 public function connect()
 {
	 if (!$this->dbConn) $this->dbConn=mysql_connect($this->dbHost,$this->dbUser,$this->dbPass) or die(mysql_error());
 }

 public function setDB()
 {		 		 
	 if ($this->dbConn) mysql_select_db($this->dbName) or die(mysql_error());
 }

 public function select($query)
 {
	 $doQuery=@mysql_query($query) or die(mysql_error());
	 if ($doQuery)
	    {
			  $this->result = mysql_fetch_assoc($doQuery);
		 }
 }

 public function getResult()
 {
	 return $this->result;
 }

 public function displayResults()
 {
	 foreach ($this->result as $key => $value)
	 {
		  print $key.': '.$value.'<br />';
	 }
 }

 public function flushResult()
 {
	 $this->result=array(); 
 }
}

$accounts=new Database();
$accounts->connect();
$accounts->setDB();
$accounts->select("select * from accounts");
//$accounts->displayResults();
var_dump($accounts->getResult());

var_dump outputs this (some identifying details changed):

array(11) { ["userID"]=> string(1) "1" ["username"]=> string(8) "sparkles" ["loginName"]=> string(16) "skittlesskittles" ["staffRanking"]=> string(1) "1" ["email"]=> string(20) "myemail@awebsite.com" ["password"]=> string(10) "mypassword" ["birthdate"]=> string(10) "0000-00-00" ["gender"]=> string(6) "female" ["activated"]=> string(3) "yes" ["activationCode"]=> string(10) "12345ABCDE" ["playedBefore"]=> string(3) "Yes" }

I probably did 100000000000 things wrong. Feel free to pick this code apart

mistin_ca

Well aside from the obvious - you shouldnt be using mysql extension.. at a minimum use mysqli (mysql improved) or PDO.

Make the adjustment here and it will work

         if ($doQuery)
            {    

                 while($res = mysql_fetch_assoc($doQuery)) {
                    $this->result[] = mysql_fetch_assoc($doQuery);  

                 }

         }

On a side note.. if you want to print arrays nicely..

echo "<pre>";
print_r($accounts->getResult()); 
echo "</pre>";

evenstar7139

How does this part of the code work:

while($res = mysql_fetch_assoc($doQuery))

I'm assuming that for every row in the result set, this statement is somehow true, and then somehow when it gets to the end, it becomes false, but I do not know how.

Edit: And wow the var dump output looks a lot better when doing it your way :o

mistin_ca

evenstar7139;1216247 wrote:
How does this part of the code work:
while($res = mysql_fetch_assoc($doQuery)) 
I'm assuming that for every row in the result set, this statement is somehow true, and then somehow when it gets to the end, it becomes false, but I do not know how.

Edit: And wow the var dump output looks a lot better when doing it your way :o

Basically think of it as foreach ($result AS $i=>$v) .. while mysql_fetch_assoc($doQuery) returns something - it does what you want it to.. where as with mysqli_fetch_assoc it does what you originally intended (which is fetch the entire result set into an assoc[] array.

Yeah, with the <pre> tags it definately makes it nicer/easier to read - it's very handy when debugging and working with API's and things of the sort.

evenstar7139

I always wondered how something like foreach() knows to move the row pointer down each time it loops. Do you know?

mistin_ca

Nope.. I'm assuming it just counts how many keys are in it before hand, then runs through it. where as while() adds 1 at a time until it returns null... im assuming

evenstar7139

What happened right here. I just saw this in a PDO tutorial and I'm not sure what's going on with the $STH variable:

$STH = $DBH->prepare("INSERT INTO folks ( first_name ) values ( 'Cathy' )");  

$STH->execute();

The variable $STH was created in the first line of code I showed. It was apparently created by having $DBH's method prepare() shoved into it. How did $STH get access to the method execute()? I don't see this as having been placed in $STH.

Thanks in advance.

mistin_ca

It's to keep it OOP..

With a db class you can continously add more/remove variables and grab data and not have to rewrite things.

So if you wanted to do 2 queries in the same page with only 1 minor difference..

$dbrun = $dbh->prepare('SELECT *
    FROM tables
    WHERE some_type < ? AND level = ?');

$dbrun->execute(array(2, 'admin'));
$result_set_one = $dbrun->fetchAll();
$dbrun->execute(array(1, 'user'));
$result_set_two = $dbrun->fetchAll();

Its very simple here, but as you start using it more you'll see the benefits ;D

NogDog

evenstar7139;1216320 wrote:
What happened right here. I just saw this in a PDO tutorial and I'm not sure what's going on with the $STH variable:
$STH = $DBH->prepare("INSERT INTO folks ( first_name ) values ( 'Cathy' )");  

$STH->execute(); 
The variable $STH was created in the first line of code I showed. It was apparently created by having $DBH's method prepare() shoved into it. How did $STH get access to the method execute()? I don't see this as having been placed in $STH.

Thanks in advance.

Just to sort of help you get used to interpreting the manual...

Assuming $DBH is a PDO object, you'll see from the manual that PDO::prepare() returns a PDOStatement object (or false on failure). One of PDOStatment's methods is execute(), so that is now accessible from the $STH object.

However, more robust code would have first checked that $STH was not false -- unless they have enabled PDO::ERRMODE_EXCEPTION earlier in the code?

evenstar7139

NogDog;1216396 wrote:
However, more robust code would have first checked that $STH was not false -- unless they have enabled PDO::ERRMODE_EXCEPTION earlier in the code?

Yup, they had it on.

NogDog;1216396 wrote:
Just to sort of help you get used to interpreting the manual...

Assuming $DBH is a PDO object, you'll see from the manual that PDO::prepare() returns a PDOStatement object (or false on failure). One of PDOStatment's methods is execute(), so that is now accessible from the $STH object.

Yeah, I always have the manual open in a tab, as I refer to it frequently. Though, to be honest, sometimes I don't understand what it's saying. If I can't get answers from the manual, I see if Google can provide me with a plain-English explanation. Sometimes this works; sometimes it doesn't.

If all else fails, I post on a PHP forum (usually this one.) It's nice to have a source of guidance from real live people--gotten me out of so many frustrating situations over the years. I don't handle frustration the greatest. I probably would have given up were it not for people like you all.

Anyhoo, let's see if I get this.

$STH = $DBH->prepare("INSERT INTO folks ( first_name ) values ( 'Cathy' )");  

$STH->execute();

PHP processed $DBH->prepare(), before it put it in $STH, so PDO::prepare() did not actually go in there, but rather its returned value did: PDO::execute(). Is this right?

I would try playing with this in my code, if I were not having a little problem. I just noticed that after removing mysql_query and mysql_select_db from my script, it's not connecting to MySQL anymore. Here is the relevant part of my code:

    private $dbHost = 'myhost'; //changed from what it really was     

    private $dbUser = 'myusername'; //changed from what it really was         

    private $dbPass = 'mypassword'; //changed from what it really was        

    private $dbName = 'mydatabase'; //changed from what it really was 
    private $DBH = false;
    public $result = array();	

 public function connect()
 { 
	 try 
	 { 
	    if (!$this->DBH) 
		 {
			 $connectString="mysql:host={$this->dbHost};dbname={$this->dbName}, {$this->dbUser}, {$this->dbPass}";
			 $this->DBH = new PDO($connectString); 
			 $DBH->setAttribute( PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION );
		 }
	 }
	 catch (PDOException $e)
	 { 
	    print $connectString.'<br /><br />'.$e->getMessage(); 
	 }

 }

I used the $connectString variable just so, upon receiving an error, I could output it to the screen and make sure that the values (like dbName) were actually getting used.

When I visit the page in my browser I get (sensitive details changed):

mysql:host=myhost;dbname=mydatabase, myusername, mypassword

SQLSTATE[28000] [1045] Access denied for user 'root'@'localhost' (using password: NO)012

I don't know how it can say it's not getting the username, or password, or anything. I see them right there in the string?

mistin_ca

   $connectString="mysql:host={$this->dbHost};dbname={$this->dbName};";
                 $this->DBH = new PDO($connectString, $this->dbUser, $this->dbPass);

Try that.

evenstar7139

Okay, I changed the code, and the error I'm getting changed to this:

Notice: Undefined variable: DBH in /pathtomyfile/Database.class.php on line 22 Fatal error: Call to a member function setAttribute() on a non-object in /pathtomyfile/Database.class.php on line 22

if (!$this->DBH) 
   {
	 $connectString="mysql:host={$this->dbHost};dbname={$this->dbName};"; 
     $this->DBH = new PDO($connectString, $this->dbUser, $this->dbPass); 
	 $DBH->setAttribute( PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION ); //this is line 22
   }

mistin_ca

evenstar7139;1216425 wrote:
Okay, I changed the code, and the error I'm getting changed to this:
if (!$this->DBH) 
   {
	 $connectString="mysql:host={$this->dbHost};dbname={$this->dbName};"; 
     $this->DBH = new PDO($connectString, $this->dbUser, $this->dbPass); 
	 $DBH->setAttribute( PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION ); //this is line 22
   }

change $dbh to $this->dbh

What you should be doing though is doing these calls in the __construct() function.. that way it init these things when you create init your pdo class..

mistin_ca

Something like


  class db { 
    private $db = NULL; 
    private $db_name = 'db';
    private $host = 'localhost';
    private $username = 'username';
    private $password = 'password';

public function __construct() { 
    try { 
        $this->db = new PDO( "mysql:dbname={$db_name};host={$this->host};", $this->username, $this->password ); 
    } 
    catch (Exception $e) { 
       // $sys->log->insert(0,1,$e);
    } 
} 
}

criterion9

if (!$this->DBH)

Do you mean to check if a variable exists or if the variable is equal to false?

if(!isset($this->DBH))

evenstar7139

mistin.ca;1216426 wrote:
change $dbh to $this->dbh

What you should be doing though is doing these calls in the __construct() function.. that way it init these things when you create init your pdo class..

My PDO class? The class we've been discussing is my database class. Do I need to make a separate class for PDO or something?

criterion9;1216431 wrote:
Do you mean to check if a variable exists or if the variable is equal to false?
if(!isset($this->DBH))

I wanted to see if it was false. I was under the impression that if a database connection fails, false was returned. Granted, I was using mysql_connect when I first wrote this class. Maybe it's different with PDO.

criterion9

If your block of code was before it had attempted a connection the variable might not be set at all (can't magically become a false value when the variable doesn't yet exist)...we would have to see the updated class in full to be sure.