How to Create a Read Only Schema in Oracle R12.

Method :1

SQL> CREATE USER APPSREAD IDENTIFIED BY APPSREAD;  
User created.
SQL>

SQL> GRANT CONNECT, RESOURCE,CREATE SYNONYM TO APPSREAD;
Grant succeeded.  
SQL>

Generate a Script for creating database objects of Application User ‘APPS’

set echo off set
pagesize 0
set linesize 300
spool cr8synonyms.sql
select 'create synonym ' || OBJECT_NAME || ' for '|| OWNER ||'.' ||OBJECT_NAME || ';' from all_objects where OWNER in ('APPS') and
OBJECT_NAME not like '%/%' and OBJECT_TYPE in ('TABLE','VIEW','SYNONYM');  
spool off

Generate a script for selecting database objects of Application User ‘APPS’

spool GrantSelect.sql  
select 'grant select on '|| OWNER ||'.' ||OBJECT_NAME || ' to APPSREAD;' from all_objects  where OWNER not in ('SYS','SYSTEM') and OBJECT_NAME not like '%/%' and OBJECT_TYPE in ('TABLE','VIEW','SYNONYM');  
spool off

Connect to sqlplus  as sysdaba and execute the following script

SQL> @GrantSelect.sql
SQL> @cr8synonyms.sql

Connect to Read only schema User and check the objects.

SQL> conn oracle/oracle Connected.
SQL> select count(*) from tab;    
COUNT(*) ----------      15515  
SQL>