Oracle Security Interview Questions And Answers

1. shutdown the database with normal/emmidiate/transactional
2. modify/include the parameter log_archive_start=true,
log_archive_dest= (location to which the redo log file
group is archived), log_archive_format=(in which format you
want to apper the archive log file)
3. start up the database

To check database is in which mode

1. Conn sys/sys as sysdba
2. select log_mode from v$database

To set database in Archivelog mode

1. shutdown immediate;
2. startup mount;
3. alter database archivelog;
4. alter database open;

To set database in NoArchivelog Mode
1. shutdown immediate;
2. startup mount;
3. alter database noarchivelog;
4. alter database open;

If a user wants to give some privileges to
another user or a group of users then they will create role
and they give this role to the users.let the privileges
be 'insert' and 'update' on 'emp' table then instead of
specifying them by their names they will create role which
inturn includes these methods. this role is further given
to the users.
If in futher if he wants to remove some
privilege given to the users, he can just alter the role
and remove that particular privilege such as he can remove
update from this created role..
Later the users cant do updations on that emp
table.but still can insert the values into that table.
Hence Roles are the easiest way to grant and
manage common privileges needed by different groups of
database users.Creating roles and assign each role to group
of users will simplify the job of assigning privileges to
individual users.

DB NAME - Must set to a text string of no more than 8
characters and it will be stored inside the datafiles,
redo log files and control files and control file while
database creation.

DB_DOMAIN - It is string that specifies the network
domain where the database is created. The global
database name is identified by setting these parameters
(DB_NAME & DB_DOMAIN)

CONTORL FILES - List of control filenames of the database.
If name is not mentioned then default name will be used.

DB_BLOCK_BUFFERS - To determine the no of buffers in the
buffer cache in SGA.

PROCESSES - To determine number of operating system
processes that can be connected to ORACLE concurrently.
The value should be 5 (background process) and
additional 1 for each user.

ROLLBACK_SEGMENTS - List of rollback segments an ORACLE
instance acquires at database startup.

Also optionally
LICENSE_MAX_SESSIONS,LICENSE_SESSION_WARNING and
LICENSE_MAX_USERS.

So many database utilities are avalibale
1. SQLPLUS
2. RMAN
3. TKPROF
4. SQLLODAR
5. EXP,IMP AND EXPDP,IMPDP
6. EXPLAN PLAN
7. LSNRCTL
etc.

DBA - role Contains all database system privileges.

SYS user account - The DBA role will be assigned to this
account. All of the basetables and views for the
database's dictionary are store in this schema and are
manipulated only by ORACLE.

SYSTEM user account - It has all the system privileges for
the database and additional tables and views that
display administrative information and internal tables and
views used by oracle tools are created using this username.

Depending on the company and the department, this role can either be highly specialized or incredibly diverse. The primary role of the Database Administrator is to adminster, develop, maintain and implement the policies and procedures necessary to ensure the security and integrity of the corporate database. Sub roles within the Database Administrator classification may include security, architecture, warehousing and/or business analysis. Other primary roles will include:

1.Deciding the h/w devices to be used
2.Deciding the user and data to be used by user.
3.Deciding the information content data base system.
4.Deciding the data dictionary contain the data in data.
5.Deciding the validation check on data.
6.Deciding the backup and recovery.
7.Monitoring the response to be changing environment.

DBA_DATA_FILES is view to show the space for the tablespace
if you want the calulate the space of the database the all
tablespace size is the database size.

Don't grant user access directly to tables within the
application.

Instead grant the ability to access the procedures that
access the tables.

When procedure executed it will execute the privilege of
procedures owner. Users cannot access tables except via the
procedure.

An user account is not a physical structure in Database
but it is having important relationship to the objects in
the database and will be having certain privileges

Profile is information contain that perticular modules.

amount of tablespace that can br used by a user for
creating his own database onjects is called talespace
quota.ita a way of limiting the usage of memory or disk
space by user or restricting him by giving a fixed disk
space.

its the tablespace in to which the objects created by a
user go.default tablespace can alloted to a user while
creating he user or can also be changed after creating the
user.
the default table space of a user is system tablespace
unless mentioned specfically while creating the user.

By creating a Role with a password

It is mean it is primary key column

RMAN is an Oracle tool for taking the backup and recovering
the databases. You can copy, restore, and recover
datafiles, control files and archived redo logs (all 3
files or any one file). It has command line utility as well
as GUI-based Enterprise Manager Backup. Here we are
discussing the command line utility.

For example, we have TEST and PROD databases. Here TEST is
the catalog database and PROD is the target database for
which the backup has to be taken. You may loose your backup
if you have your catalog and target databases on the same
box and the box crashes .So it is always advisable to keep
a separate database for RMAN catalog .

Create two databases. One for RMAN catalog(Test) and one
target(PROD). Both the Databases should be archive log mode
(for security).

A view is a logical table based on a table or another view.
A view contain no data itself but it is like a window
through which data from tables can be views and changed.
A sequence is a user created database object that can be
shared by multiple user to generate unique integers.

Database on other servers can be updated and those
transactions can be grouped together with others in a
logical unit.
Database uses a two phase commit.

snapshort log is used updated data for master table and if
any recored is updated after certen peried to referse the
master table collect the snapshot log. because tha table
size is very large it take lot of time. thus by ues the
snapshot log.

It is a table that maintains a record of modifications to
the master table in a snapshot. It is stored in the same
database as master table and is only available for simple
snapshots. It should be created before creating snapshots.

COMPLETE - Tables are completly regenerated using
the snapshot's query and the master tables every time the
snapshot referenced.

FAST - If simple snapshot used then a snapshot log can be
used to send the changes to the snapshot tables.

FORCE - Default value. If possible it performs a FAST
refresh; Otherwise it will perform a complete refresh.

Time the references to occur when master tables are not in use.
Peform the reference the manually immdiately locking the
master tables. We can join tables in snopshots by creating
a complex snapshots that will based on the master tables.

Dynamic data replication is feture of oracle actualy the to
more database ex:- this is production database and other
database with and synconoze with the production databse
throuth the dynamic replication. if any change the proction
database the symaltantinasly change the other database the
replication. the benefite the the user can access any were
ether prodction or syn with other database.

A simple snapshot is based on a query that does not
contains GROUP BY clauses, CONNECT BY clauses, JOINs,
sub-query or snashot of operations.
- A complex snapshots contain atleast any one of the above.

snapshots is three types of complite,fast and force.