CQL native aggregates 

Works on a set of rows matching the SELECT statement to return a single value.

Aggregate functions work on a set of rows matching a cql_commands/cqlSelect.html statement to return a single value. Null values in the data set are ignored. When other columns, columns with user-defined types, or functions, are also specified in the selector clause of a SELECT statement with an aggregate function, the values in the first row matching the query are returned.
CAUTION:
Aggregating data across partitions may cause performance issues. DataStax recommends using aggregates on one partition, to get a list of partition keys use cql_commands/cqlSelect.html cql_commands/cqlSelect.html#cqlSelect__distinct to get a list of unique keys (for compound keys use a comma separated list of column names).
Tip: Define custom aggregates using CREATE AGGREGATE.

Synopsis 

aggregate_name(column_name)
Where the system aggregate names are listed below:
AVG(column_name)
Provides the average value of the target column using the data type of target column. Null values are ignored.

Only works on numeric columns, that is refDataTypes.html#refDataTypes__tinyint, refDataTypes.html#refDataTypes__smallint, refDataTypes.html#refDataTypes__int, refDataTypes.html#refDataTypes__bigint, refDataTypes.html#refDataTypes__decimal, refDataTypes.html#refDataTypes__float, and refDataTypes.html#refDataTypes__double.

COUNT(column_name)
Provides the number of rows in the result set that do not have null values. For a complete row count use partition key column, since partition keys cannot contain nulls.

Works on all CQL data types columns.

MIN(column_name)
Provides the smallest value. Null values are ignored.

Only works numeric columns, that is refDataTypes.html#refDataTypes__tinyint, refDataTypes.html#refDataTypes__smallint, refDataTypes.html#refDataTypes__int, refDataTypes.html#refDataTypes__bigint, refDataTypes.html#refDataTypes__decimal, refDataTypes.html#refDataTypes__float, and refDataTypes.html#refDataTypes__double.

MAX(column_name)
Provides the largest value. Null values are ignored.

Only works numeric columns, that is refDataTypes.html#refDataTypes__tinyint, refDataTypes.html#refDataTypes__smallint, refDataTypes.html#refDataTypes__int, refDataTypes.html#refDataTypes__bigint, refDataTypes.html#refDataTypes__decimal, refDataTypes.html#refDataTypes__float, and refDataTypes.html#refDataTypes__double.

SUM(column_name)
Provides the column total. Null values are ignored.

Only works numeric columns, that is refDataTypes.html#refDataTypes__tinyint, refDataTypes.html#refDataTypes__smallint, refDataTypes.html#refDataTypes__int, refDataTypes.html#refDataTypes__bigint, refDataTypes.html#refDataTypes__decimal, refDataTypes.html#refDataTypes__float, and refDataTypes.html#refDataTypes__double.