presto-main/src/main/java/io/prestosql/sql/analyzer/Scope.java/Scope/Scope
class Scope:    private Scope(
            Optional<Scope> parent,
            boolean queryBoundary,
            RelationId relationId,
            RelationType relation,
            Map<String, WithQuery> namedQueries)
    {
        this.parent = requireNonNull(parent, "parent is null");
        this.relationId = requireNonNull(relationId, "relationId is null");
        this.queryBoundary = queryBoundary;
        this.relation = requireNonNull(relation, "relation is null");
        this.namedQueries = ImmutableMap.copyOf(requireNonNull(namedQueries, "namedQueries is null"));
    }