How to schedule a job to run every other Sunday of a week in dbms_scheduler

If I want to run a job every Sunday at Midnight then the expression for subsequent executions would be like:

Subsequent Execution Expression: NEXT_DAY(TRUNC(SYSDATE), 'SUNDAY')

job query will look like following:

 SYS.DBMS_JOB.SUBMIT
    ( job       => NewJobID 
     ,what      => 'X_Process'
     ,next_date => TO_DATE('8/2/2023 11:45:00 AM', 'MM/DD/YYYY HH:MI:SS AM')
     ,interval  => 'NEXT_DAY(TRUNC(SYSDATE), 'SUNDAY')'
     ,no_parse  => FALSE);
  SYS.DBMS_OUTPUT.PUT_LINE
    ('Job Number is: ' || to_char(NewJobID));
  COMMIT;

But I need to execute the job every other Sunday means the job will run One week on Sunday then the following week's Sunday it will not run. But after that, it will run again next week's Sunday.
So execution will be twice in a four-week span.

So what will be the Expression for this interval?

Here are a few options related to dbms_scheduler (which is what you specified in title, while code you posted contains dbms_job. Switch to dbms_scheduler, it is more powerful).

Option one: run job "weekly" with interval of "2" (so, every other week) on "SUN"day at "11" hours "45" minutes:

BEGIN
   DBMS_SCHEDULER.CREATE_JOB (
      job_name         => 'My_job',
      job_type         => 'PLSQL_BLOCK',
      job_action       => 'begin x_process; end;',
      start_date       =>
         TO_TIMESTAMP_TZ ('06.08.2023 11:45 Europe/Zagreb', 'dd.mm.yyyy hh24:mi TZR'),
      repeat_interval  => 'FREQ=WEEKLY; INTERVAL=2; BYDAY=SUN; BYHOUR=11; BYMINUTE=45',
      enabled          => TRUE,
      comments         => 'Job runs every other Sunday');
END;
/

Option two: run job "monthly" on "1st, 3rd and 5th Sunday" at "11:45"; if there are only 4 Sundays in month, the 5th won't be executed):

repeat_interval  => 'FREQ=MONTHLY; BYDAY=1SUN,3SUN,5SUN; BYHOUR=11; BYMINUTE=45',

Option three: run job "yearly", every other week (you have to specify all week numbers from 1 to 53, one-by-one (I put "..." because I didn't fell like typing all of them) on "Sunday" at "11:45":

repeat_interval  => 'FREQ=YEARLY; BYWEEKNO=1,3,5,7,9,11,...,49,51,53; BYDAY=SUN; BYHOUR=11; BYMINUTE=45',

There might be other options; hopefully, someone else will suggest them.

Also, have a look at <a href="https://docs.oracle.com/en/database/oracle/oracle-database/19/arpls/DBMS_SCHEDULER.html#GUID-73622B78-EFF4-4D06-92F5-E358AB2D58F3">DBMS_SCHEDULER</A> documentation for more information.

As of DBMS_JOB vs. DBMS_SCHEDULER: you'd rather not use DBMS_JOB any longer. <a href="https://docs.oracle.com/en/database/oracle/oracle-database/19/admin/support-for-DBMS_JOB.html#GUID-CC42E8DA-7203-449E-BCEA-8187ECC4BCDF">Support for DBMS_JOB</a> (19c version; the newest is 23 free) Oracle documentation says:

> Oracle Scheduler replaces the DBMS_JOB package. Although DBMS_JOB is still supported for backward compatibility, Oracle strongly recommends that you switch from DBMS_JOB to Oracle Scheduler.

so it is expected that it'll become deprecated / desupported. You should switch to DBMS_SCHEDULER.