COUNTD_APPROX
Syntax
Standard
Extended
COUNTD_APPROX( value )
COUNTD_APPROX( value
[ FIXED ... | INCLUDE ... | EXCLUDE ... ]
[ BEFORE FILTER BY ... ]
)
More info:
Description
Returns the approximate number of unique values in the group. Faster than COUNTD, but doesn't guarantee accuracy.
Argument types:
value—Any
Return type: Integer
Example
COUNTD_APPROX([ClienID])
Data source support
ClickHouse 19.13.