AVG

Syntax

Purpose

AVG returns average value of expr.

This function takes as an argument any numeric data type or any nonnumeric data type that can be implicitly converted to a numeric data type. The function returns the same data type as the numeric data type of the argument.

If you specify DISTINCT, then you can specify only the query_partition_clause of the analytic_clause. The order_by_clause and windowing_clause are not allowed.

Aggregate Example

The following example calculates the average salary of all employees in the hr.employees table:

SELECT AVG(salary) "Average"
 FROM employees;
 Average
--------------
 6461.83178

Analytic Example

The following example calculates, for each employee in the employees table, the average salary of the employees reporting to the same manager who were hired in the range just before through just after the employee:

SELECT manager_id, last_name, hire_date, salary,
 AVG(salary) OVER (PARTITION BY manager_id ORDER BY hire_date 
 ROWS BETWEEN 1 PRECEDING AND 1 FOLLOWING) AS c_mavg
 FROM employees
 ORDER BY manager_id, hire_date, salary;
MANAGER_ID LAST_NAME HIRE_DATE SALARY C_MAVG
---------- ------------------------- --------- ---------- ----------
 100 De Haan 13-JAN-01 17000 14000
 100 Raphaely 07-DEC-02 11000 11966.6667
 100 Kaufling 01-MAY-03 7900 10633.3333
 100 Hartstein 17-FEB-04 13000 9633.33333
 100 Weiss 18-JUL-04 8000 11666.6667
 100 Russell 01-OCT-04 14000 11833.3333
 100 Partners 05-JAN-05 13500 13166.6667
 100 Errazuriz 10-MAR-05 12000 11233.3333
. . .