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I am using a lightweight PHP MVC (homegrown--not by me--but based off of Codeigniter) to develop a web application. Currently, I only have one object--the User.

The web application allows each user to curate a collection (let's say the user has a collection of different animals) and manipulate the collection on the fly. One page in the site will define the set of animals' behaviors and the other will specify appearance. If the user deletes an animal while defining behavior, however, that animal should be removed from the collection once the user moves to the appearance tab.

Could (should) each animal be an Object? I know in Java I could pass an array of objects to a another Object in my application, but am not sure if this is possible/common in PHP (this would be the ideal implementation).

Alternatively, if I were to store all of the animals in some sort of data structure, could I pass that data structure between views (from the client side via AJAX?)

I don't want to store this information in a database because then, between each page load I would have to query the database anew to see if any changes had been made.

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How many views do you use per page? Or are the two views, that you mentioned, producing two different interfaces: one for html page and one for ajax response. It's kinda confusing (especially, since CI pretends that views are just glorified templates). –  tereško Jun 19 at 16:59
 
One view per page (the pages have very different functionality) and two pages - so two views. –  Diana E Jun 19 at 17:02
 
Ask yourself why you don't want to use a database. This is what they are for! Querying mysql for the sort of data you mention takes about a microsecond if the query is complex and less if it is simple. If you really feel like self-flagellation, you could store the data in CSV, JSON or XML and load into memory for each use, but the application will not scale well. Mysql will handle the data transactions faster than any code you or I are likely to write. If you have two pages, you don't need ajax to transfer the data. Just get php to write it each time you view it. Once again, mysqli_*... –  Robert Seddon-Smith Jun 19 at 20:12
 
@RobertSeddon-Smith - this makes sense, thanks for the response. This application will involve a lot of dragging and dropping via HTML5's canvas. I wouldn't want to make the database call every time the user dropped something on the canvas. Ideally, the collection would save (i.e., the DB would be updated), once the user left a particular page. Is there any way to do that? Thanks in advance. –  Diana E Jun 19 at 20:54
 
Yes, you can call javascript onunload method then copy the data. Try typing half an answer here, then closing the browser - you will see a simple version of onunload in action, in this case calling confirm. use an ajax call from within your onunload function to do this. –  Robert Seddon-Smith Jun 20 at 6:50
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That is indeed possible but only with some sort of persistent storage. PHP lives only during a request. Once the user sees the finished "product", no PHP script runs anymore and so every information, that is not stored in the HTML or somewhere else, is lost. That being said you need some sort of storage.

Yes database queries every time something changes might be a performance-hit. But you can do one thing that is straightforward and easy to handle. *) In the one view where the user can define the behaviour, you direct the user upon submit back to the same controller he came from. This controller then reads all the relevant data from HTML (what and how depends on how your data is represented anyway). This read data will be used to update the existing set. Then the user gets redirected to the appearance controller and it's view.

*) The whole data structure is serialized and saved in a file. That is easy to read and easy to write. If you decide to use a database, you can use this file as caching. Whenever changes occur, the cache is deleted and the database updated. The next time a controller needs data and doesn't find the cache, the cache is recreated from the database. Unless you change the data on every page, that is a massive performance boost.

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