Improvement Oracle installation guide http://platform.xwiki.org/xwiki/bin/view/AdminGuide/InstallationOracle

Necessary installation steps are below. It is not a good idea to give the xwiki user all privileges. With it, a malicious user can even erase files on the UNIX filesystem.

– Create user.
create user xwiki identified by PASSWORD

– Create a separate tablespace ("database" on SQL Server/MySQL) to hold the data.
select *
from dba_data_files

create tablespace xwiki
datafile '/opt/SOMETHING/oracle/oradata/SID/xwiki01.dbf'
size 1m
autoextend on maxsize 1g

– Set the default tablespace.
alter user xwiki
default tablespace xwiki
temporary tablespace temp

– Allow access (logon and create table privs).
grant create session to xwiki

grant create table to xwiki

– Allow writing in tablespace.
alter user xwiki quota unlimited on xwiki