Question

I was reading this article:
Managing Oracle Synonyms

Regarding the order of preference, when it come to resolving an object name to the actual object, it says:

1. Local objects will always be accessed first.

2. If a local object does not exist, the object with a private synonym will be accessed.

3. If a private synonym does not exist or the object does not exist, then the public synonym will be used.

I was wondering if the public objects are missing in this order somehow?

E.g. if user BOB queries

select * from FOOBAR

and there is no BOB.FOOBAR in dba_tables/views but PUBLIC.FOOBAR.

Does Oracle resolve it to PUBLIC.FOOBAR or will it check for synonyms first?

Thank you.

Answer 1

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 name

SQL> CREATE TABLE system.foobar (id integer);

Table created

SQL> 

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”.