SQL AVG()Function
AVG() Function
The AVG() function returns the average value of a numeric column.
SQL AVG() Syntax
SELECT AVG(column_name) FROM table_name
Demonstration Database
In this tutorial, we will use the EXAMPLE sample database.
The following is data selected from the "access_log" table:
+-----+---------+-------+------------+ | aid | site_id | count | date | +-----+---------+-------+------------+ | 1 | 1 | 45 | 2016-05-10 | | 2 | 3 | 100 | 2016-05-13 | | 3 | 1 | 230 | 2016-05-14 | | 4 | 2 | 10 | 2016-05-14 | | 5 | 5 | 205 | 2016-05-14 | | 6 | 4 | 13 | 2016-05-15 | | 7 | 3 | 220 | 2016-05-15 | | 8 | 5 | 545 | 2016-05-16 | | 9 | 3 | 201 | 2016-05-17 | +-----+---------+-------+------------+
SQL AVG() Example
The following SQL statement gets the average value from the "count" column of the "access_log" table:
Example
SELECT AVG(count) AS CountAverage FROM access_log;
After executing the above SQL, the output result is as follows:
The following SQL statement selects the "site_id" and "count" whose visits are higher than the average visits:
Example
SELECT site_id, count FROM access_log
WHERE count > (SELECT AVG(count) FROM access_log);
WHERE count > (SELECT AVG(count) FROM access_log);
After executing the above SQL, the output result is as follows:
Other Extensions