groupBitmap
Bitmap or Aggregate calculations from a unsigned integer column, return cardinality of type UInt64, if add suffix -State, then return bitmap object.
groupBitmap(expr)
Arguments
expr – An expression that results in UInt* type.
Return value
Value of the UInt64 type.
Example
Test data:
UserID
1
1
2
3
Query:
SELECT groupBitmap(UserID) as num FROM t
Result:
num
3