-- https://docs.oracle.com/en/database/oracle/oracle-database/23/sqlrf/ALTER-TABLE.html
ALTER TABLE sales SPLIT PARTITION SALES_Q1_2002 INTO (
 PARTITION SALES_JAN_2002 VALUES LESS THAN (TO_DATE('01-FEB-2002','DD-MON-YYYY')),
 PARTITION SALES_FEB_2002 VALUES LESS THAN (TO_DATE('01-MAR-2002','DD-MON-YYYY')),
 PARTITION SALES_MAR_2002);