Question:
What is the ora_dba group used for?
Why is it important to have an ora_dba group in Windows?
Answer: When you install Oracle on
Windows, a special Windows local group called ora_dba
is created. This is the equivalent of the /etc/group
concept in UNIX/Linux. When a Windows user is assigned
to the ora_dba group, they are OS-level DBA work
such as starting and stopping the database and listener
services. This is referred as SYSDBA privileges. For
information on dba group membership in Linux/UNIX, see my
notes on etc/group.
Attempting a privileged Windows operation without being
assigned to the ora_dba group leads to the
ORA-0103 insufficient privileges error.
There are two or three key groups on Windows:
Administrators,
ora_dba, and ora_oper. The
first two are musts, and the
ora_oper is entirely optional.
You do not necessarily have to belong to the
ora_dba, administrators group, but
you or someone else does when Oracle is first installed.
With Oracle on Windows, you get the
ora_dba group for free. Creating
groups on Windows is typically in the purview of an
administrator. The
ora_dba group is similar to the
oinstall or dba groups created on UNIX, and membership
does have its privileges.