# DISTINCTCOUNTHLLPLUS

## Signature

> DISTINCTCOUNTHLLPLUS(colName, log2m)

## Usage Examples

## **DISTINCTCOUNTHLLPLUS considerations**

* `DISTINCTCOUNTHLL()`is faster than `DISTINCTCOUNT()`if data is pre-aggregated at ingestion or aggregated at a server with enough records. This performance improvement increases when comparing large datasets.
* If very few records are pre-aggregated, `DISTINCTCOUNTHLL()`will not be as fast as `DISTINCTCOUNT()`because the serialized HLL size is larger than sending individual values.
* `DISTINCTCOUNTHLLPLUS()`provides more precise results than `DISTINCTCOUNTHLL()`with the same performance.
* `DISTINCTCOUNTSMARTHLL()`automatically shifts to HLL when reaching a threshold, and comes with some overhead.


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