[Sheryld]

метод для проверки целостности таблицы дерева(не оптимизирован):

function checkTree()
		{
			$db = new MySql(null, "mport4", null, null);
			$db->MySql_Connect();
			$db->MySql_SelectDb();
			
			//left key always less then right key
			$selectQuery = "select cat_ID from categories  
					where cat_LEFT >= cat_RIGHT";
			
			$db->MySql_QueryDb($selectQuery);
			
			if ($db->dbResult != null)
			{
				$this->errors[] = "Левый ключ всегда меньше правого ключа.";
				//echo "error 1";
				//return -1;
			}
			
			//smallest key always equal 1 and biggest key always equal 2*n-elemetns
			$selectQuery = "SELECT min( cat_LEFT ) 
			as minKey, max( cat_RIGHT ) 
			as maxKey, count( * ) 
			as nElements
			FROM categories";
			
			$db->MySql_QueryDb($selectQuery);
			
			if ($db->dbResult != null)
			{
				while($row = mysql_fetch_assoc($db->dbResult))
				{				
					if ($row["minKey"] != 1 || ($row["maxKey"] % $row["nElements"]) != 0)
					{
						$this->errors[] = "Ключи корневой ветки неправильные.";
					}
				}				
			} 
			
			// cat_RIGHT-cat_LEFT/2 always not equal 0
			$selectQuery = "SELECT mod(cat_RIGHT-cat_LEFT,2) as os 
			FROM `categories` 
			GROUP BY cat_ID 
			HAVING os = 0";
			
			$db->MySql_QueryDb($selectQuery);
			
			if ($db->dbResult != null)
			{
				$this->errors[] = "Разница между правым и левым ключами должна быть отрицательна.";
			}
			
			//need fix?
			$selectQuery = "SELECT mod((cat_LEFT-cat_LEVEL+2),2) as os 
			FROM categories 
			HAVING os = 0";
			
			$db->MySql_QueryDb($selectQuery);
			
			if ($db->dbResult != null)
			{
				$this->errors[] = "Ошибка 4.";
			}
			
			//all keys must be unique
			$keys = array();
			
			$selectQuery = "SELECT cat_LEFT, cat_RIGHT 
			FROM categories"; 

			$db->MySql_QueryDb($selectQuery);
			
			if ($db->dbResult != null)
			{
				while($row = mysql_fetch_assoc($db->dbResult))
				{
					$keys[] = $row["cat_LEFT"];
					$keys[] = $row["cat_RIGHT"];
				}
				//return "error 5";
			}
			
			//$keys[] = 1;
			
			if ($keys !== array_unique($keys))
			{
				$this->errors[] = "Все ключи должны быть уникальны.";
			}
			
			if (!empty($this->errors))
			{
				return -1;
			}
			return 0;
		}