preferable example for getting data method for model

01_first.php

<?php

class Post extends AppModel {

	/**
	 * Usage:
	 * $nextPost = $this->Post->getNext(1);
	 */
	public function getNext($id) {
		$greater = $this->find('first', array(
			'conditions' => array(
				'Post.id >' => $id,
			),
		));

		if ($greater) {
			return $greater;
		}

		$littler = $this->find('first', array(
			'conditions' => array(
				'Post.id <' => $id,
			),
		));
		return $littler;
	}

}

02_category_required.php

<?php

class Post extends AppModel {

	public $belongsTo = array(
		'Category',
	);

	/**
	 * Usage:
	 * $nextPost = $this->Post->getNext(1, 'CakePHP');
	 */
	public function getNext($id, $category) {
		$greater = $this->find('first', array(
			'conditions' => array(
				'Post.id >' => $id,
				'Category.name' => $category,
			),
		));

		if ($greater) {
			return $greater;
		}

		$littler = $this->find('first', array(
			'conditions' => array(
				'Post.id <' => $id,
				'Category.name' => $category,
			),
		));
		return $littler;
	}

}

03_category_scoped.php

<?php

class Post extends AppModel {

	public $belongsTo = array(
		'Category',
	);

	/**
	 * Usage:
	 * $nextPost = $this->Post->getNext(1);
	 * $nextPost = $this->Post->getNext(1, 'CakePHP');
	 */
	public function getNext($id, $category = null) {
		$categoryScope = $category === null ? array() : array(
			'Category.name' => $category,
		);
		$greater = $this->find('first', array(
			'conditions' => array(
				'Post.id >' => $id,
			) + $categoryScope,
		));

		if ($greater) {
			return $greater;
		}

		$littler = $this->find('first', array(
			'conditions' => array(
				'Post.id <' => $id,
			) + $categoryScope,
		));
		return $littler;
	}

}

04_tagged.php

<?php

class Post extends AppModel {

	public $belongsTo = array(
		'Category',
	);

	/**
	 * Usage:
	 * $nextPost = $this->Post->getNext(1);
	 * $nextPost = $this->Post->getNext(1, 'CakePHP');
	 * $nextPost = $this->Post->getNext(1, 'CakePHP', 'tips');
	 * $nextPost = $this->Post->getNext(1, null, 'tips');
	 */
	public function getNext($id, $category = null, $tag = null) {
		$categoryScope = $category === null ? array() : array(
			'Category.name' => $category,
		);

		$tagScope = $tagQuery = array();
		if ($tag !== null) {
			$tagScope = array(
				'Tag.name' => $tag,
			);
			$tagQuery = array(
				'joins' => array(
					array(
						'alias' => 'PostsTag',
						'table' => 'posts_tags',
						'conditions' => '`PostsTag`.`post_id` = `Post`.`id`',
						'type' => 'RIGHT',
					),
					array(
						'alias' => 'Tag',
						'table' => 'tags',
						'conditions' => '`PostsTag`.`tag_id` = `Tag`.`id`',
						'type' => 'RIGHT',
					),
				),
				'group' => 'Post.id',
			);
		}

		$greater = $this->find('first', array(
			'conditions' => array(
				'Post.id >' => $id,
			) + $categoryScope + $tagScope,
		) + $tagQuery);

		if ($greater) {
			return $greater;
		}

		$littler = $this->find('first', array(
			'conditions' => array(
				'Post.id <' => $id,
			) + $categoryScope + $tagScope,
		) + $tagQuery);

		return $littler;
	}

}

05_custom_find_property.php

<?php

class Post extends AppModel {

	public $belongsTo = array(
		'Category',
	);

	var $_findMethods = array(
		'next' => true,
	);

}

06_custom_find_method.php

<?php

class Post extends AppModel {

	public $belongsTo = array(
		'Category',
	);

	var $_findMethods = array(
		'next' => true,
	);

	/**
	 * Usage:
	 * $nextPost = $this->Post->find('next', array(
	 * 	'id' => 1,
	 * 	...
	 * ));
	 */
	protected function _findNext($state, $query, $results = array()) {
		if ($state == 'before') {
			$greaterQuery = Set::merge($query, array(
				'conditions' => array(
					'Post.id >' => $query['id'],
				),
			));
			$greaterExists = $this->find('count', $greaterQuery);
			if (!$greaterExists) {
				$littlerQuery = Set::merge($query, array(
					'conditions' => array(
						'Post.id <' => $query['id'],
					),
				));
				$query = $littlerQuery;
			} else {
				$query = $greaterQuery;
			}
			unset($query['id']);

			$query['order'] = array(
				'Post.id' => 'ASC',
			);
			$query['limit'] = 1;

			return $query;
		} elseif ($state == 'after') {
			if (empty($results[0])) {
				return false;
			}
			return $results[0];
		}
	}

}

07_custom_find_reuse.php

<?php

class Post extends AppModel {

	public $belongsTo = array(
		'Category',
	);

	var $_findMethods = array(
		'next' => true,
	);

	/**
	 * Usage:
	 * $nextPost = $this->Post->find('next', array(
	 * 	'id' => 1,
	 * 	...
	 * ));
	 */
	protected function _findNext($state, $query, $results = array()) {
		if ($state == 'before') {
			$greaterQuery = Set::merge($query, array(
				'conditions' => array(
					'Post.id >' => $query['id'],
				),
			));
			$greaterExists = $this->find('count', $greaterQuery);
			if (!$greaterExists) {
				$littlerQuery = Set::merge($query, array(
					'conditions' => array(
						'Post.id <' => $query['id'],
					),
				));
				$query = $littlerQuery;
			} else {
				$query = $greaterQuery;
			}
			unset($query['id']);

			$query['order'] = array(
				'Post.id' => 'ASC',
			);

			return $this->_findFirst($state, $query, $results);
		} elseif ($state == 'after') {
			return $this->_findFirst($state, $query, $results);
		}
	}

}

08_before_find.php

<?php

class Post extends AppModel {

	public $belongsTo = array(
		'Category',
	);

	var $_findMethods = array(
		'next' => true,
	);

	/**
	 * Usage:
	 * $nextPost = $this->Post->find('next', array(
	 * 	'id' => 1,
	 * 	...
	 * ));
	 */
	protected function _findNext($state, $query, $results = array()) {
		if ($state == 'before') {
			$greaterQuery = Set::merge($query, array(
				'conditions' => array(
					'Post.id >' => $query['id'],
				),
			));
			$greaterExists = $this->find('count', $greaterQuery);
			if (!$greaterExists) {
				$littlerQuery = Set::merge($query, array(
					'conditions' => array(
						'Post.id <' => $query['id'],
					),
				));
				$query = $littlerQuery;
			} else {
				$query = $greaterQuery;
			}
			unset($query['id']);

			$query['order'] = array(
				'Post.id' => 'ASC',
			);

			return $this->_findFirst($state, $query, $results);
		} elseif ($state == 'after') {
			return $this->_findFirst($state, $query, $results);
		}
	}

	/**
	 * Available find keys:
	 * 'category': adding creteria with name of category.
	 * 'tag': adding creteria and additional association with name of tag.
	 */
	public function beforeFind($query = array()) {
		if (array_key_exists('category', $query)) {
			$query = Set::merge($query, array(
				'conditions' => array(
					'Category.name' => $query['category'],
				),
			));
			unset($query['category']);
		}

		if (array_key_exists('tag', $query)) {
			$query = Set::merge($query, array(
				'conditions' => array(
					'Tag.name' => $query['tag'],
				),
				'joins' => array(
					array(
						'alias' => 'PostsTag',
						'table' => 'posts_tags',
						'conditions' => '`PostsTag`.`post_id` = `Post`.`id`',
						'type' => 'RIGHT',
					),
					array(
						'alias' => 'Tag',
						'table' => 'tags',
						'conditions' => '`PostsTag`.`tag_id` = `Tag`.`id`',
						'type' => 'RIGHT',
					),
				),
				'group' => 'Post.id',
			));
			unset($query['tag']);
		}

		return $query;
	}

}

999_last.php

<?php

class Post extends AppModel {

	public $belongsTo = array(
		'Category',
	);

	public $actsAs = array(
		'FindNext',
		'Categorize',
		'Taggable',
	);

}