presto-main/src/main/java/io/prestosql/operator/aggregation/ApproximateSetAggregation.java/ApproximateSetAggregation/input
class ApproximateSetAggregation:    @InputFunction
    public static void input(@AggregationState HyperLogLogState state, @SqlType(StandardTypes.BIGINT) long value)
    {
        HyperLogLog hll = getOrCreateHyperLogLog(state);
        state.addMemoryUsage(-hll.estimatedInMemorySize());
        hll.add(value);
        state.addMemoryUsage(hll.estimatedInMemorySize());
    }