Oracle DBA Interview Questions 4

1) What is the use of root.sh & oraInstRoot.sh?
Ans:
Changes ownership & permissions of oraInventory
Creating oratab file in the /etc directory
In RAC, starts the clusterware stack


2) How can you transport tablespaces across platforms with different endian formats?
Ans:
RMAN

3) What is transportable tablespace (and across platforms)?

4)  What is xtss (cross platform transportable tablespace)?

5)  What is the difference between restore point & guaranteed restore point?

6) How to find if your Oracle database is 32 bit or 64 bit?
Ans:
execute the command "file $ORACLE_HOME/bin/oracle", you should see output like /u01/db/bin/oracle: ELF 64-bit MSB executable SPARCV9 Version 1

means you are on 64 bit oracle.

If your oracle is 32 bit you should see output like below
oracle: ELF 32-bit MSB executable SPARC Version 1


7) How to find opatch Version ?
Ans:
opatch is utility to apply database patch, In order to find opatch version execute"$ORACLE_HOME/OPatch/opatch version"


8) suppose i created one table after few days i did some insert,update how can i know when will i did ddl or dml operation is undergone on that table ?

ANS:

DDL:

select OWNER,OBJECT_NAME,CREATED,LAST_DDL_TIME,from dba_objects where OBJECT_NAME='&object_name';


DML:

SQL> select max(ora_rowscn), scn_to_timestamp(max(ora_rowscn)) from PS_PAY_TAX;

MAX(ORA_ROWSCN) SCN_TO_TIMESTAMP(MAX(ORA_ROWSCN))
--------------- ---------------------------------------------------------------------------
     6016929147 04-JAN-12 08.41.20.000000000 AM

SQL>

SQL> select table_name, inserts, updates, deletes, timestamp,truncated  from user_tab_modifications where table_name='TEST1';

TABLE_NAME  INSERTS    UPDATE  DELETES   TIMESTAMP         TRU DROP_SEG

---------   --------  ------- -------- ------------------- --- --------

TEST1        4         0        0     04.08.2008 12:03:32  NO   0