Use the ADD partitioning-clause of the ALTER TABLE statement to change a nonpartitioned table into a partitioned table. Altering an existing table to use partitions is similar to creating a new partitioned table.
For example, to add range partitioning to the nonpartitioned table PAYROLL, use the following code:
ALTER TABLE PRODLIB.PAYROLL ADD PARTITION BY RANGE(EMPNUM) (STARTING(MINVALUE) ENDING(500) INCLUSIVE, STARTING(501) ENDING(1000) INCLUSIVE, STARTING(1001) ENDING MAXVALUE))