Sparse: Intro

Sparse is a simple yet fairly powerful way of making PHP pages that are driven by SQL. Sparse allows you to create a simple HTML page (or even fragment) that defines how your page will look and interact with the data, and all the back-end stuff, including displaying, editing, adding, and updating data, navigation, searching, sorting, showing error messages, etc., will all be handled by Sparse. What's more, you can mix and match Sparse code with regular form inputs and regular code, meaning that you only have to code the really complex stuff yourself; everything else is done for you!

In addition, Sparse outputs every form in degradable Ajax, cutting down on server-side computation and bandwidth, and giving your user a smoother interface. If your user has Javascript disabled, no problem: the regular functionality will take over.

It's probably easiest to just show you an example. Here it is (assuming you have a table "myTable" in the database "myDB" with four fields named ID, Field1, Field2, and Field3):

<?php
    include('Sparse.php');
    SparseThisPage('myUsername', 'myPassword');
?>
<!DOCTYPE html
PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html>
<body>
<sqltemplate database="myDB" tables="myTable" limit="10" type="display">
    <table border='1'>
<tr>
<th>ID</th>
<th>Field1</th>
<th>Field2</th>
<th>Field3</th>
</tr>
    <sqlrow>
    <tr>
    <td><sqlfield name="ID" /></td>
<td><sqlfield name="Field1" /></td>
  <td><sqlfield name="Field2" /></td>
<td><sqlfield name="Field3" /></td>
</tr>
    </sqlrow>
    </table>
</sqltemplate>
</body>
</html>

The first thing you should notice is the PHP code at the top. Those two lines are all you need to get Sparse going! (Although you can replace the username and password with strings or other PHP variables.) The rest of the page, complete with HTML and style info, and even other PHP code, can remain as is.

Ladies and gents, please draw your attention to the first unique tag, sqltemplate. This is the main tag enclosing your template. Note that you can have multiple sqltemplates in a single document if you so choose. This tag allows you to designate what kind of template it is (in this case, it'll simply display the data, as evidence by its display type) and what the associated data should be (in this case, we just want the first 10 rows in the "myTable" table).

After that comes the sqlrow tag. Everything within this tag will be repeated for each row of the data returned from the query computed from the sqltemplate tag.

Finally comes the biggie, the sqlfield tag. This indicates where the data should go. If it's an editable table, it will print an appropriate widget (text box, textarea, radio button etc.). Otherwise it'll simply print the data. The "name" attribute indicates what column of the query should go there.

And voila: your table looks something like this:

ID	Field1	Field2	Field3
1	dog	15.32	2005-06-07
100	cat	1234.54	2005-12-21
753	camel	-24.6	2005-01-01

Note that although our example using SparseThisPage is probably the easiest and most common usage, you don't need to solely use it this way. You can save different templates in XML files, with HTML fragments rather than full pages. You can display the templates on the fly by using the PHP functions.

Although Sparse is simple to use, it's also quite powerful in that it allows you a lot of control over the look and behavior of your form without a lot of work. You can change the style of any element; You can define where the error messages should be and what they should look like; you can force fields to become particular widgets; you can easily do input validation or change around the values before updating them. Sparse is both usable and flexible.

You can even use a super-compressed version of the template, like so:

Now that you've got a taste of it, why not dive deeper into the features?

Introduction | Next: Templates - Overview

Sparse - Introduction