<?php
$connection = mysql_connect(
"localhost",
"root",
""
);
mysql_select_db(
"test",
$connection
);
//////////////////////////////////////////////////////////////////////
//
// MySQL tables used in the following examples.
//
//////////////////////////////////////////////////////////////////////
/*
CREATE TABLE `categories` (
`id` int(11) NOT NULL auto_increment,
`title` varchar(255) NOT NULL default '',
`description` varchar(255) NOT NULL default '',
PRIMARY KEY (`id`)
) ENGINE=MyISAM;
INSERT INTO `categories`(
`title`,
`description`
) VALUES (
'General',
'This is the general category.'
);
CREATE TABLE `articles` (
`id` int(11) NOT NULL auto_increment,
`category_id` int(11) NOT NULL default '0',
`title` varchar(255) NOT NULL default '',
`introduction` varchar(255) NOT NULL default '',
`article` varchar(255) NOT NULL default '',
PRIMARY KEY (`id`)
) ENGINE=MyISAM;
INSERT INTO `articles`(
`category_id`,
`title`,
`introduction`,
`article`
) VALUES (
1,
'Hello, World!',
'The introduction of the lame hello, world article.',
'The article body of the lame hello, world article.'
);
CREATE TABLE `comments` (
`id` int(11) NOT NULL auto_increment,
`article_id` int(11) NOT NULL default '0',
`comment` varchar(255) NOT NULL default '',
PRIMARY KEY (`id`)
) ENGINE=MyISAM;
INSERT INTO `comments`(
`article_id`,
`comment`
) VALUES (
1,
'First comment!'
);
INSERT INTO `comments`(
`article_id`,
`comment`
) VALUES (
1,
'Second comment!'
);
*/
//////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////
//
// Extend the class using a database table name as class name. The class
// name need not be the exact capitalization of the table name.
//
//////////////////////////////////////////////////////////////////////
// Require the class to be extended.
require_once("mysql_model.class.php");
class Articles extends MySQL_Model
{
// Handle id and auto arguments in the constructor.
function Articles($id = 0, $auto = "")
{
// Initialize the Model class with proper arguments.
$this -> init($id, $auto);
$this -> belongs_to_one(
"categories", // The `categories` table.
"id", // The foreign key in the `categories` table.
"category_id" // The key in the `articles` table.
);
$this -> has_many(
"comments", // The `comments` table.
"article_id" // The foreign key in the `comments` table.
// Assumed is the auto key in the `articles` table.
);
}
}
//////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////
//
// Find all articles.
//
//////////////////////////////////////////////////////////////////////
$a = new Articles();
$articles = $a -> find();
// Loop through the articles, printing them to the screen.
for($i = 0; $i < count($articles); $i++)
{
echo $articles[$i]["categories"]["title"] . "\t";
echo $articles[$i]["title"] . "\n";
}
//////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////
//
// Attempt to create a new record. Cause an error to be generated when
// `category_id` is not provided.
//
// NOTE: If a column does not allow NULL values, it is considered by
// the MySQL_Model class to be required.
//
// The only thing we must do after catching the error is set `category_id`
// to some value and attempt to save() again. The data persists after
// the call to save().
//
// NOTE: If you provide an `id` to the Articles constructor and eventually
// call save(), this will update the record, not create a new one.
//
//////////////////////////////////////////////////////////////////////
$a = new Articles();
// Set fields, leaving one blank to cause an error.
$a -> set("category_id", 0);
$a -> set("title", "...");
$a -> set("introduction", "...");
$a -> set("article", "...");
// Save and catch errors in data validation.
if(!$a -> save())
{
// Print the error array to the screen.
print_r($a -> error());
}
//////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////
//
// Display managed data structure.
//
// Assuming an Article with the `id` '1' exists, this will look in the
// `categories` and `comments` tables and attach all records matching:
//
// "articles.category_id = categories.id"
// and
// "articles.id = comments.article_id"
//
// This is considered a lazy join due to the absence of an actual join
// clause in the sql. This allows for much simpler code and the ability to
// greatly modify the behavior of values returned by this kind of join.
//
// You will note that after printing out the fields array there is a new
// field titled 'comments' which contains an array of values found in the
// `comments` table.
//
// You will also notice a single array has been attached called
// `categories` which contains the record found in the `categories` table.
//
// NOTE: When using has_many(), the attached array will be an array of
// assoc array's. When using has_one(), the attached array will be an
// assoc array.
//
// NOTE: You can call these functions as many times as you'd like. It
// simply continues to add to the fields.
//
//////////////////////////////////////////////////////////////////////
$a = new Articles(1);
print_r($a -> get_fields());
//////////////////////////////////////////////////////////////////////
mysql_close(
$connection
);
?>
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