Get the maximum value of a column with MySQL Aggregate function

To get the maximum value of a column, MySQL has a predefined aggregate function MAX(). Let us first create a table −

mysql> create table DemoTable (    Id int ); Query OK, 0 rows affected (0.96 sec)

Insert some records in the table using insert command −

mysql> insert into DemoTable values(100); Query OK, 1 row affected (0.13 sec) mysql> insert into DemoTable values(988); Query OK, 1 row affected (0.10 sec) mysql> insert into DemoTable values(1000); Query OK, 1 row affected (0.12 sec) mysql> insert into DemoTable values(99); Query OK, 1 row affected (0.17 sec) mysql> insert into DemoTable values(999); Query OK, 1 row affected (0.12 sec)

Display all records from the table using select statement −

mysql> select *from DemoTable;

This will produce the following output −

+------+ | Id | +------+ | 100 | | 988 | | 1000 | | 99 | | 999 | +------+ 5 rows in set (0.00 sec)

Following is the query to get the maximum value of a column −

mysql> select max(Id) AS MaxId from DemoTable;

This will produce the following output −

+-------+ | MaxId | +-------+ | 1000 | +-------+ 1 row in set (0.03 sec)