columnar::ColumnInfo Node1 columnar::ColumnInfo + index + type + accessMode + isOffset + isOptional + addMTDependency   Node2 std::string     Node2->Node1 +name +offsetName +replacesColumn +variantLinkKeyColumn Node3 std::basic_string< Char >     Node3->Node2 Node4 std::vector< unsigned > + elements + elements   Node4->Node1 +fixedDimensions Node5 std::vector< std::string > + elements + elements   Node5->Node1 +linkTargetNames