I can't modify a created job

Question

I want to modify a job that I created. but I get 'A database object was specified that does not exist' at the level of name => 'jb_do'
BEGIN
SYS.DBMS_SCHEDULER.set_attribute ( name => 'jb_do', attribute => 'JOB_ACTION', value=> 'myProcedure'); END ;

Answer 1

Well, it works for me in SQL*Plus:
SQL> VARIABLE v_job CHAR(30);
SQL>
SQL> EXEC :v_job := 'my_job';
PL/SQL procedure successfully completed.
SQL>
SQL> VARIABLE v_action CHAR(50);
SQL>
SQL> EXEC :v_action := 'BEGIN NULL; END;';
PL/SQL procedure successfully completed.
SQL>
SQL> BEGIN
  2      SYS.DBMS_SCHEDULER.set_attribute (
  3          name => 'GVA.' || :v_job,
  4          attribute => 'JOB_ACTION',
  5          value=> :v_action);
  6  END;
  7  /
PL/SQL procedure successfully completed.
SQL>
What is the exact and complete error message you get?