code: private function getKeys(): array
  	{
  		/* @var $result Key[] */
  		$result = [];
  		$rows = $this->connection->query("
  			SELECT 
  				[INDEX_NAME],
  				[COLUMN_NAME],
  				[INDEX_TYPE],
  				[NON_UNIQUE],
  				[SEQ_IN_INDEX]
  			FROM [information_schema.STATISTICS] 
  			WHERE [TABLE_SCHEMA] = %s
  				AND [TABLE_NAME] = %s 
  				AND [INDEX_NAME] != %s",
  			$this->database,
  			$this->name,
  			'PRIMARY');
  		foreach ($rows as $row) {
  			$name = $row->INDEX_NAME;
  			if (isset($result[$name])) {
  				$obj = $result[$name];
  			} else {
  				$obj = new Key;
  			}
  			$obj->name = $name;
  			$obj->addColumn($row->SEQ_IN_INDEX, $row->COLUMN_NAME);
  			$obj->type = $row->INDEX_TYPE;
  			$obj->unique = !$row->NON_UNIQUE;
  
  			$result[$name] = $obj;
  		}
  		return $result;
  	}
docs: Vrati schema klicu
  @return Key[]
  @throws QueryException