	public function addJoin( $tableAlias, $joinConditions ) {
		if ( empty( $tableAlias ) || empty( $joinConditions ) ) {
			throw new \MWException( __METHOD__ . ': An empty join clause was passed.' );
		}
		if ( isset( $this->join[$tableAlias] ) ) {
			throw new \MWException( __METHOD__ . ': Attempted to overwrite existing join clause.' );
		}
		$this->join[$tableAlias] = $joinConditions;
		return true;
	}
The software does not properly control the allocation and maintenance of a limited resource, thereby enabling an actor to influence the amount of resources consumed, eventually leading to the exhaustion of available resources.