Common Oracle Security Interview Preparation Guide

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By setting the following values in init.ora file.

LOG_ARCHIVE_FORMAT = arch %S/s/T/tarc (%S - Log sequence
number and is zero left paded, %s - Log sequence
number not padded. %T - Thread number lef-zero-paded and
%t - Thread number not padded). The file name created is
arch 0001 are if %S is used.
LOG_ARCHIVE_DEST = path.

To perform one of these function on an index,table, or cluster:

- to collect statisties about object used by the
optimizer and store them in the data dictionary.
- to delete statistics about the object used by
object from the data dictionary.
- to validate the structure of the object.
- to identify migrated and chained rows of the table or
cluster.

Replication of data in distributed enviroonment.
Using snapshots to replicate data.
Using remote procedure calls.

snapshot is nothing but a consistance data for master table
if any chance the master table snapshot is fatch the
updated data for master table.

snapshots is three types of complite,fast and force.

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.

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.

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.

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.

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.

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.

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.

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.

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).

It is mean it is primary key column

By creating a Role with a password

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.

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.

Profile is information contain that perticular modules.

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

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.

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.

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 - 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.

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.