In Oracle, ADD_MONTHS function adds the number of month to the specified date value. In MariaDB, you have to use TIMESTAMPADD function even in Oracle Compatibility mode.
Oracle:
ALTER SESSION SET NLS_DATE_FORMAT = 'YYYY-MM-DD HH24:MI:SS'; -- Add 2 months to the current date SELECT ADD_MONTHS(SYSDATE, 2) FROM dual; # 2021-07-19 12:14:17
MariaDB - Oracle Compatibility:
-- Add 2 months to the current date SELECT TIMESTAMPADD(MONTH, 2, SYSDATE()); # 2021-07-19 12:14:17
Note that the order of parameters for ADD_MONTHS and TIMESTAMPADD changed.
For more information, see Oracle to MariaDB Migration - Oracle Compatibility Mode.