presto-raptor-legacy/src/main/java/io/prestosql/plugin/raptor/legacy/metadata/Distribution.java/Mapper/map
class Mapper:        @Override
        public Distribution map(int index, ResultSet rs, StatementContext ctx)
                throws SQLException
        {
            List<Type> types = LIST_CODEC.fromJson(rs.getString("column_types")).stream()
                    .map(TypeId::of)
                    .map(typeManager::getType)
                    .collect(toImmutableList());

            return new Distribution(
                    rs.getLong("distribution_id"),
                    Optional.ofNullable(rs.getString("distribution_name")),
                    types,
                    rs.getInt("bucket_count"));
        }