This function is preview. It is currently not supported by Microsoft Support. For additional limitations, see Remarks.
Returns the approximate number of rows that contain distinct values in a column. This function can query large amounts of data with potentially better performance than DISTINCTCOUNT, with slight deviation from the exact result.
|column||The column that contains the values to be counted. This cannot be an expression.|
The approximate number of distinct values in column.
The only argument to this function is a column. You can use columns containing any type of data. When the function finds no rows to count, it returns a BLANK, otherwise it returns the count of distinct values.
This function is preview. The following limitations apply:
This function currently supports DirectQuery connections only to the following data sources:
- Azure SQL Database
- Azure SQL Data Warehouse
This feature is not yet available in Intellisense.