You can not select more than 25 topics
			Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
		
		
		
		
		
			
		
			
				
					
					
						
							75 lines
						
					
					
						
							2.3 KiB
						
					
					
				
			
		
		
	
	
							75 lines
						
					
					
						
							2.3 KiB
						
					
					
				<?php | 
						|
/** | 
						|
 * @link http://www.yiiframework.com/ | 
						|
 * @copyright Copyright (c) 2008 Yii Software LLC | 
						|
 * @license http://www.yiiframework.com/license/ | 
						|
 */ | 
						|
 | 
						|
namespace yii\caching; | 
						|
 | 
						|
use Yii; | 
						|
use yii\base\InvalidConfigException; | 
						|
use yii\db\Connection; | 
						|
 | 
						|
/** | 
						|
 * DbDependency represents a dependency based on the query result of a SQL statement. | 
						|
 * | 
						|
 * If the query result changes, the dependency is considered as changed. | 
						|
 * The query is specified via the [[sql]] property. | 
						|
 * | 
						|
 * @author Qiang Xue <qiang.xue@gmail.com> | 
						|
 * @since 2.0 | 
						|
 */ | 
						|
class DbDependency extends Dependency | 
						|
{ | 
						|
	/** | 
						|
	 * @var string the application component ID of the DB connection. | 
						|
	 */ | 
						|
	public $db = 'db'; | 
						|
	/** | 
						|
	 * @var string the SQL query whose result is used to determine if the dependency has been changed. | 
						|
	 * Only the first row of the query result will be used. | 
						|
	 */ | 
						|
	public $sql; | 
						|
	/** | 
						|
	 * @var array the parameters (name=>value) to be bound to the SQL statement specified by [[sql]]. | 
						|
	 */ | 
						|
	public $params; | 
						|
 | 
						|
	/** | 
						|
	 * Constructor. | 
						|
	 * @param string $sql the SQL query whose result is used to determine if the dependency has been changed. | 
						|
	 * @param array $params the parameters (name=>value) to be bound to the SQL statement specified by [[sql]]. | 
						|
	 * @param array $config name-value pairs that will be used to initialize the object properties | 
						|
	 */ | 
						|
	public function __construct($sql, $params = array(), $config = array()) | 
						|
	{ | 
						|
		$this->sql = $sql; | 
						|
		$this->params = $params; | 
						|
		parent::__construct($config); | 
						|
	} | 
						|
 | 
						|
	/** | 
						|
	 * Generates the data needed to determine if dependency has been changed. | 
						|
	 * This method returns the value of the global state. | 
						|
	 * @throws InvalidConfigException | 
						|
	 * @return mixed the data needed to determine if dependency has been changed. | 
						|
	 */ | 
						|
	protected function generateDependencyData() | 
						|
	{ | 
						|
		$db = Yii::$app->getComponent($this->db); | 
						|
		if (!$db instanceof Connection) { | 
						|
			throw new InvalidConfigException("DbDependency::db must be the application component ID of a DB connection."); | 
						|
		} | 
						|
 | 
						|
		if ($db->enableQueryCache) { | 
						|
			// temporarily disable and re-enable query caching | 
						|
			$db->enableQueryCache = false; | 
						|
			$result = $db->createCommand($this->sql, $this->params)->queryRow(); | 
						|
			$db->enableQueryCache = true; | 
						|
		} else { | 
						|
			$result = $db->createCommand($this->sql, $this->params)->queryRow(); | 
						|
		} | 
						|
		return $result; | 
						|
	} | 
						|
}
 | 
						|
 |