presto-main/src/main/java/io/prestosql/type/QuantileDigestOperators.java/QuantileDigestOperators/castFromVarbinaryBigint
class QuantileDigestOperators:    @ScalarOperator(CAST)
    @SqlType("qdigest(bigint)")
    public static Slice castFromVarbinaryBigint(@SqlType(StandardTypes.VARBINARY) Slice slice)
    {
        return slice;
    }