PostgreSQL avg () function

PostgreSQL avg () function

The AVG function of PostgreSQL is used to find the average value of a field in various records.

To understand the AVG function, the table COMPANY has the following records:
Testdb # select * from COMPANY;
Id | name | age | address | salary
---- + ------- + ----- + ----------- + --------
1 | Paul | 32 | California | 20000
2 | Allen | 25 | TX | 15000
3 | Teddy | 23 | Norway | 20000
4 | Mark | 25 | Rich-Mond | 65000
5 | David | 27 | Texas | 85000
6 | Kim | 22 | South-Hall | 45000
7 | James | 24 | houaston | 10000
(7 rows)
 

Now, if you want to calculate the average salary based on the above table, you can use the following command: www.bkjia.com
Testdb = # select avg (SALARY) from company;

The above PostgreSQL table will produce the following results:
Avg
------------------
37142.8571428571
(1 row)
 

The average group by clause can be used to set various records. In the following example, all related records of a person are averaged, and the average salary of each person is calculated.
Testdb = # SELECT name, AVG (SALARY) from company group by name;
Name | avg
------- + -------
Teddy | 20000
Paul | 20000
Mark | 65000
David | 85000
Allen | 15000
Kim | 45000
James | 10000
(7 rows)

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