Oracle® Database SQL Language Reference 11g Release 2 (11.2) Part Number E10592-02 |
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Syntax
See Also:
"Analytic Functions" for information on syntax, semantics, and restrictionsPurpose
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.
See Also:
Table 3-10, "Implicit Type Conversion Matrix" for more information on implicit conversionIf 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 -------------- 6461.68224
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, c_mavg; 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 . . .