Biggest value from two or more fields in MySQL?

To know the biggest value from two or more fields, use the function GREATEST() from MySQL.

The syntax is as follows −

SELECT GREATEST(MAX(yourColumnName1),MAX(yourColumnName2),...............MAX(yourColumnName2) ) from yourTableName;

Let us understand the above concept by creating a table with more than two columns −

mysql> create table GreatestOfTwoOrMore
   -> (
   -> Marks1 int,
   -> Marks2 int,
   -> Marks3 int
   -> );
Query OK, 0 rows affected (0.57 sec)

Here is the query to insert records in a table −

mysql> insert into GreatestOfTwoOrMore values(23,78,89);
Query OK, 1 row affected (0.16 sec)
mysql> insert into GreatestOfTwoOrMore values(50,100,150);
Query OK, 1 row affected (0.24 sec)
mysql> insert into GreatestOfTwoOrMore values(100,500,2000);
Query OK, 1 row affected (0.15 sec)

Display all the values inserted above using the following query −

mysql> select *from GreatestOfTwoOrMore;

The following is the output −

+--------+--------+--------+
| Marks1 | Marks2 | Marks3 |
+--------+--------+--------+
|     23 |     78 |     89 |
|     50 |    100 |    150 |
|    100 |    500 |   2000 |
+--------+--------+--------+
3 rows in set (0.00 sec)

Let us implement the above concept using the following query to get the biggest value from two or more fields.

The query is as follows −

mysql> SELECT GREATEST(MAX(marks1),MAX(marks2),MAX(marks3)) from GreatestOfTwoOrMore;

The following is the output −

+-----------------------------------------------+
| GREATEST(MAX(marks1),MAX(marks2),MAX(marks3)) |
+-----------------------------------------------+
|                                          2000 |
+-----------------------------------------------+
1 row in set (0.06 sec)