Managing Oracle Synonyms

In your example, FOOBAR is almost certainly a public synonym. There is no PUBLIC schema but PUBLIC is listed as the owner of a public synonym.

If I create a new public synonym

SQL> create public synonym pub_syn_emp  2     for scott.emp;Synonym created.

the owner of that synonym ends up being PUBLIC

SQL> edWrote file afiedt.buf  1  select object_name, owner, object_type  2    from dba_objects  3*  where object_name = 'PUB_SYN_EMP'SQL> /OBJECT_NAME          OWNER      OBJECT_TYP-------------------- ---------- ----------PUB_SYN_EMP          PUBLIC     SYNONYM

In addition, item #3 does not appear to be correct. If there is a private synonym that points to a non-existent object and a public synonym that points to a valid object, the private synonym still takes precedence. You'll just get an error when Oracle tries to resolve the private synonym to an actual object.

SQL> create synonym syn_emp for scott.no_such_table;Synonym created.SQL> create public synonym syn_emp for scott.emp;Synonym created.SQL> select * from syn_emp;select * from syn_emp              *ERROR at line 1:ORA-00980: synonym translation is no longer valid

At least up to 10g, PUBLIC is not a real user. You cannot create objects in the "Public schema":

SQL> CREATE TABLE public.foobar (id integer);CREATE TABLE public.foobar (id integer)ORA-00903: invalid table nameSQL> CREATE TABLE system.foobar (id integer);Table createdSQL> 

If you run this query:

SELECT object_name   FROM dba_objects  WHERE owner='PUBLIC'    AND object_type IN ('TABLE', 'VIEW');

You can answer the question about pre-defined tables/views in the PUBLIC "schema".