Syntax
MAX([ DISTINCT | ALL ] expr) OVER (analytic_clause)
Purpose
Returns the maximum value in the specified data.
The value of MAX() can be a string parameter. In these cases, it returns the maximum string value.
The
DISTINCTkeyword specifies to find the maximum value of differentexprvalues. The result is the same as if you omitDISTINCT.The
ALLkeyword specifies to find allexprvalues. The default isALL.
Examples
obclient> CREATE TABLE EXPLOYEES(LAST_NAME CHAR(10), SALARY DECIMAL, JOB_ID CHAR(32));
Query OK, 0 rows affected
obclient> INSERT INTO EXPLOYEES VALUES('JIM', 2000, 'CLEANER');
Query OK, 1 row affected
obclient> INSERT INTO EXPLOYEES VALUES('MIKE', 12000, 'ENGINEERING');
Query OK, 1 row affected
obclient> INSERT INTO EXPLOYEES VALUES('LILY', 13000, 'ENGINEERING');
Query OK, 1 row affected
obclient> INSERT INTO EXPLOYEES VALUES('TOM', 11000, 'ENGINEERING');
Query OK, 1 row affected
obclient> SELECT LAST_NAME, MAX(SALARY) OVER (PARTITION BY JOB_ID) MAX_S FROM EXPLOYEES;
+-----------+-------+
| LAST_NAME | MAX_S |
+-----------+-------+
| JIM | 2000 |
| MIKE | 13000 |
| LILY | 13000 |
| TOM | 13000 |
+-----------+-------+
4 rows in set