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MySQL query to find the average of only first three values from a column with five values
For this, you can use a subquery. Let us first create a table −
mysql> create table DemoTable ( Score int ); Query OK, 0 rows affected (0.62 sec)
Insert some records in the table using insert command −
mysql> insert into DemoTable values(80); Query OK, 1 row affected (0.13 sec) mysql> insert into DemoTable values(45); Query OK, 1 row affected (0.13 sec) mysql> insert into DemoTable values(55); Query OK, 1 row affected (0.33 sec) mysql> insert into DemoTable values(78); Query OK, 1 row affected (0.20 sec) mysql> insert into DemoTable values(88); Query OK, 1 row affected (0.13 sec)
Display all records from the table using select statement −
mysql> select *from DemoTable;
This will produce the following output −
+-------+ | Score | +-------+ | 80 | | 45 | | 55 | | 78 | | 88 | +-------+ 5 rows in set (0.00 sec)
Following is the query to find the average of only the first three column values. Here, we are using LIMIT 3 to find the average of only three records −
mysql> select avg(Score) from ( select Score from DemoTable limit 3) tbl;
This will produce the following output −
+------------+ | avg(Score) | +------------+ | 60.0000 | +------------+ 1 row in set (0.00 sec)
Updated on: 04-Oct-2019
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