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Oracle Sample Questions : Oracle Database Administration

An Oracle database may not always be accessible to all users. To open or shut a database, or to start up or shut down an example, you must have DBA (Database Administrator) privileges. Here we will discuss some important facts about Oracle Database Administration and it is also very important for you to know that the Oracle sample questions given below and Oracle Webserver Sample Questions are two entirely different things.

11. Where can I get a list of all hidden Oracle parameters?

    Answer: Oracle initialization or INIT.ORA parameters with a underscore in front is hidden or unsupported parameters.You can get a list of all hidden parameters by doing:

    SELECT *

    FROMSYS.X$KSPPI

    WHERE SUBSTR(KSPPINM,1,1) = '_';

12. How can I give developers access to trace files required as input to tkprof?

    Answer: The "alter session set sql_trace=true" command generates trace files in USER_DUMP_DEST that is used by developers as input to tkprof.

    There is an undocumented INIT.ORA parameter that will allow everybody to read this trace files:

    _trace_files_public = true

    Include this in your INIT.ORA file and bounce your database for it to take effect.

13. How can I see what the uptime for my database is?

    Answer: column STARTED format a18 head 'STARTUP TIME'

    select C.INSTANCE,

    to_date(JUL.VALUE, 'J')

    ||to_char(floor(SEC.VALUE/3600),'09' )

    ||':'

    ||substr (to_char(mod(SEC.VALUE/60, 60), '09'), 2, 2)

    ||'.'

    ||substr (to_char(mod(SEC.VALUE, 60), '09'), 2, 2)

    STARTED

    from V$INSTANCE JUL,

    V$INSTANCE SEC,

    V$THREADC

    where JUL.KEY like '%JULIAN%'

    and SEC.KEY like '%SECOND%';

14. How can I become another user in Oracle?

    Answer: Of course it is not advisable to bridge Oracle's security, but look at this example:

    SQL> select password from dba_users where username='SCOTT';

    PASSWORD

    F894844C34402B67

    SQL> alter user scott identified by lion;

    User altered.

    SQL> connect scott/lion

    Connected.

    REM Do whatever you like

    SQL> connect system/manager

    Connected.

    SQL> alter user scott identified by values 'F894844C34402B67';

    User altered.

    SQL> connect scott/tiger

    Connected.

Above we discussed about Oracle ODBC Connectivity. For additional information on Computer language we have also discussed on Oracle SQL Net Sample Questions to help students to score good marks. Our next entry on Oracle interview sample questions will also help you clear the interview and get a good job ahead.