Loading multiple models into one controller and setting them

Written By
Shadow  
Submitted At
2010-03-01 15:24:06  
Num Views
885  
Category
CakePHP  
I have a question.. Say you have a controller with a function called home. In this controller I need to load and set images, details, titles etc from about 5 different tables, to display randomly on page load. How would I go about it?

By Shadow @ 2010-03-01 15:24:06
Ok let's work with 3 tables as after that you would just duplicate the rest of the code for more.

Tables: Book, DVD, Games

In your controller create a function called getRandomProducts

function getRandomProducts($itemCount = 1){
//gets all the models which you are going to need to use to pull info from the database
$this->loadModel('Book');
$this->loadModel('Dvd');
$this->loadModel('Game');

//this fetches all the fields in the tables Book,Dvd,Game and sets to $books,$dvds,$games
$books = $this->Book->findAll();
$dvds = $this->Dvd->findAll();
$games = $this->Game->findAll();

//loops through the books rows and pulls the id,title and sets the type to books
for($i = 0; $i < sizeof($books); $i++){
$newRow['id'] = $books[$i]['Book']['id'];
$newRow['title'] = $books[$i]['Book']['title'];
$newRow['type'] = 'books';

$allRows[] = $newRow;
}

//loops through the dvd rows and pulls the id,title and sets the type to dvd
for($i = 0; $i < sizeof($dvds); $i++){
$newRow['id'] = $dvds[$i]['Dvd']['id'];
$newRow['title'] = $dvds[$i]['Dvd']['title'];
$newRow['type'] = 'dvds';

$allRows[] = $newRow;
}

//loops through the games rows and pulls the id, title and sets the type to games
for($i = 0; $i < sizeof($games); $i++){
$newRow['id'] = $games[$i]['Game']['id'];
$newRow['title'] = $games[$i]['Game']['title'];
$newRow['type'] = 'games';

$allRows[] = $newRow;
}

//now we have a variable called $allRows which has all products in book,dvd and games with their id and type
//you can print_r($allRows) here to see what the structure looks like

//we now need to get the amount of products we have so that we can give that number to the php
//random function to know we want a value between 0 and the number of products seeing that
//our $allRows array will start with 0 and end at the number of products we currently have.

//our minimum value is zero because our allRows array starts at 0
$minValue = 0;

//our max value is the count of $allRows - 1. This is because the function count() returns the number
//of elements in the array $allRows which is 1 to much because an array starts with 0 and not like
//normal counting which starts at 1, thats why we subtract the 1
$maxValue = count($allRows) - 1;

$randomItems = array();
for($i = 0; $i < $itemCount;$i++){
//the function rand will return a random number between or equal to the minValue and maxValue given
//we then set $randomIndex as that is our random number in the array $allRows
$randomIndex = rand($minValue,$maxValue);

$randomItem = $allRows[$randomIndex];

if(!in_array($randomItem,$randomItems)){
//all thats needed now is to add the element if it has not been added already
$randomItems[] = $randomItem;
}else{
$i--;
}
}

return $randomItems;
}


Now you can call this function wherever you want and it will return a random item.

So in your function home you can call it like this

function home(){
//runs the function getRandomProduct and send you want 6 items returned, gets the result in $randomProducts
$randomProducts = $this->getRandomProducts(6);
//print it out to see it works, you can remove this
echo "<pre>RANDOM PRODUCTS HERE:";print_r($randomProducts);echo "</pre>";
}

By PHPin24 @ 2010-03-03 09:58:57
If all your colums were the same in the different tables you could alternatively just add a column called 'type' which will make your code a LOT less.

So lets say you had a table called products

function getRandomProduct(){
//gets the model which you are going to need to use to pull info from the database
$this->loadModel('Product');

//this fetches all the fields in the table Product
$products = $this->Product->findAll();

//our minimum value is zero because our products array starts at 0
$minValue = 0;

//our max value is the count of $products - 1. This is because the function count() returns the number
//of elements in the array $products which is 1 to much because an array starts with 0 and not like
//normal counting which starts at 1, thats why we subtract the 1
$maxValue = count($products) - 1;

//the function rand will return a random number between or equal to the minValue and maxValue given
//we then set $randomIndex as that is our random number in the array $products
$randomIndex = rand($minValue,$maxValue);

//all thats needed now is to return the element
$randomItem = $products[$randomIndex];

return $randomItem;
}

By PHPin24 @ 2010-03-03 10:26:35
Dude. That is amazing. It works perfectly.
Will definitely put all my items in one table next time!
Thanks for the GREAT reply!

By Shadow @ 2010-03-03 11:31:59
Just something I picked up reading this, rather use:

$this->Product->find('all');



instead of:

$this->Product->findAll();



as the findAll() method is going to be deprecated in future releases of cake.

Also, while I'm here, if you'd like to speed up your for loops, use:


for ($x = 0, $s = sizeof($productsArray); $x < $s; ++$x)
{
        // Some code here
}


because you don't want to calculate the size of the array each time you iterate through the loop. In larger array's, this uses quite a bit more processing power and is best avoided altogether.

Lastly, if you don't want to keep writing all this:


echo "<pre>RANDOM PRODUCTS HERE:";print_r($randomProducts);echo "</pre>";



You could just use Cake's handy debug() method, like so, which does the same thing:

debug($randomProducts);



Just make sure that the debug level is greater than 0 in your /app/config/core.php file ;)

Just my 2 cents :)


By snivels @ 2010-03-06 01:26:17
Thanks for the update. It's great feedback and always good to know future developments in CakePHP ex: the findAll function being deprecated in CakePHP 1.3

Just to clarify speeding up the loops:
As snivels suggested. Rather use:
$sizeOfProducts = sizeof($productsArray);
for ($x = 0, $s = $sizeOfProducts; $x < $s; ++$x){
        // Some code here
}


Just to confirm the debug function is quite useful if you have debugging enabled.



By PHPin24 @ 2010-03-09 16:16:47