This is another curious error message that i presume is rare to be seen twice in your life.
alter session set tracefile_identifier="";Oracle accepts the double quotes as string delimiter, but not when there is nothing in between.
ORA-01741: illegal zero-length identifier
In fact it is perfectly possible to execute:
alter session set tracefile_identifier="xyz";
where name = 'tracefile_identifier';
In order to set the session parameter to a null value, single quotes must be used:
alter session set tracefile_identifier='';Note also that ALTER SESSION, unlike ALTER SYSTEM, doesn't come with an ALTER...RESET... clause.
See message translations for ORA-01741 and search additional resources.