QueryRoot
   Projection
      ProjectionElemList
         ProjectionElem "o"
         ProjectionElem "o2"
      FedXLeftJoin
         StatementSourcePattern
            Var (name=s)
            Var (name=_const_99282aab_uri, value=http://purl.org/dc/terms/source, anonymous)
            Var (name=o)
            StatementSource (id=endpoint1, type=REMOTE)
            StatementSource (id=endpoint2, type=REMOTE)
         ExclusiveStatement
            Var (name=s)
            Var (name=_const_dbb1cdc8_uri, value=http://purl.org/dc/terms/title, anonymous)
            Var (name=o2)
            StatementSource (id=endpoint2, type=REMOTE)
