| description |
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This section contains reference documentation for the DISTINCTCOUNTHLL function. |
Returns an approximate distinct count using HyperLogLog. It also takes an optional second argument to configure the log2m for the HyperLogLog.
For accurate distinct counting, see DISTINCTCOUNT.
DISTINCTCOUNTHLL(colName, log2m)
These examples are based on the Batch Quick Start.
select DISTINCTCOUNTHLL(teamID) AS value
from baseballStats | value |
|---|
| 158 |
select DISTINCTCOUNTHLL(teamID, 12) AS value
from baseballStats | value |
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| 149 |