public boolean isOutputOrdered ( List < AbstractExpression > sortExpressions , List < SortDirectionType > sortDirections ) { assert ( sortExpressions . size ( ) == sortDirections . size ( ) ) ; if ( m_children . size ( ) == 1 ) { return m_children . get ( 0 ) . isOutputOrdered ( sortExpressions , sortDirections ) ; } return false ; }
Does the plan guarantee a result sorted according to the required sort order . The default implementation delegates the question to its child if there is only one child .