what country is bordered by poland and germany on the north side?
return country ;return the  north side of #1 ;return poland ;return germany ;return #1 where  #2 is bordered by #3 ;return #1 where  #2 is bordered by #4 ;return #1 in  both  #5 and #6
['select', 'project', 'select', 'select', 'comparative', 'comparative', 'intersection']