MAX

Syntax

MAX([DISTINCT  ALL] expr)

Purpose

You can call this function to return the maximum value in the specified data set.

The argument of MAX() can be a string, in which case the maximum string value is returned. The DISTINCT keyword specifies to evaluate only distinct values. By default, ALL is used.

Examples

Assume that Table a has the following three data rows: id=1,num=10, id=2,num=20, and id=3,num=30, you can execute the following statement to obtain the maximum num:

obclient> SELECT MAX(num) FROM a;
+-----------------+
 MAX(num)        
+-----------------+
              30 
+-----------------+
1 row in set (0.00 sec)