Thursday, October 18, 2012

Temporary Tablespace Related Scripts

To check instance-wise total allocated, total used TEMP for both rac and non-rac

set lines 152
col FreeSpaceGB format 999.999
col UsedSpaceGB format 999.999
col TotalSpaceGB format 999.999
col host_name format a30
col tablespace_name format a30
select tablespace_name,
(free_blocks*8)/1024/1024 FreeSpaceGB,
(used_blocks*8)/1024/1024 UsedSpaceGB,
(total_blocks*8)/1024/1024 TotalSpaceGB,
i.instance_name,i.host_name
from gv$sort_segment ss,gv$instance i where ss.tablespace_name in (select tablespace_name from dba_tablespaces where contents='TEMPORARY') and
i.inst_id=ss.inst_id;

Total Used and Total Free Blocks

select inst_id, tablespace_name, total_blocks, used_blocks, free_blocks  from gv$sort_segment;

Another Query to check TEMP USAGE

col name for a20
SELECT d.status "Status", d.tablespace_name "Name", d.contents "Type", d.extent_management
"ExtManag",
TO_CHAR(NVL(a.bytes / 1024 / 1024, 0),'99,999,990.900') "Size (M)", TO_CHAR(NVL(t.bytes,
0)/1024/1024,'99999,999.999') ||'/'||TO_CHAR(NVL(a.bytes/1024/1024, 0),'99999,999.999') "Used (M)",
TO_CHAR(NVL(t.bytes / a.bytes * 100, 0), '990.00') "Used %"
FROM sys.dba_tablespaces d, (select tablespace_name, sum(bytes) bytes from dba_temp_files group by
tablespace_name) a,
(select tablespace_name, sum(bytes_cached) bytes from
v$temp_extent_pool group by tablespace_name) t
WHERE d.tablespace_name = a.tablespace_name(+) AND d.tablespace_name = t.tablespace_name(+)
AND d.extent_management like 'LOCAL' AND d.contents like 'TEMPORARY';

Temporary Tablespace groups

SELECT * FROM DATABASE_PROPERTIES where PROPERTY_NAME='DEFAULT_TEMP_TABLESPACE';

select tablespace_name,contents from dba_tablespaces where tablespace_name like '%TEMP%';

select * from dba_tablespace_groups;

Block wise Check

select TABLESPACE_NAME, TOTAL_BLOCKS, USED_BLOCKS, MAX_USED_BLOCKS, MAX_SORT_BLOCKS, FREE_BLOCKS from V$SORT_SEGMENT;

select sum(free_blocks) from gv$sort_segment where tablespace_name = 'TEMP';
To Check Percentage Usage of Temp Tablespace

select (s.tot_used_blocks/f.total_blocks)*100 as "percent used"
from (select sum(used_blocks) tot_used_blocks
from v$sort_segment where tablespace_name='TEMP') s,
(select sum(blocks) total_blocks
from dba_temp_files where tablespace_name='TEMP') f;

To check Used Extents ,Free Extents available in Temp Tablespace

SELECT tablespace_name, extent_size, total_extents, used_extents,free_extents, max_used_size FROM v$sort_segment;

To list all tempfiles of Temp Tablespace

col file_name for a45
select tablespace_name,file_name,bytes/1024/1024,maxbytes/1024/1024,autoextensible from dba_temp_files  order by file_name;

SELECT d.tablespace_name tablespace , d.file_name filename, d.file_id fl_id, d.bytes/1024/1024
size_m
, NVL(t.bytes_cached/1024/1024, 0) used_m, TRUNC((t.bytes_cached / d.bytes) * 100) pct_used
FROM
sys.dba_temp_files d, v$temp_extent_pool t, v$tempfile v
WHERE (t.file_id (+)= d.file_id)
AND (d.file_id = v.file#);

Additional checks

select distinct(temporary_tablespace) from dba_users;

select username,default_tablespace,temporary_tablespace from dba_users order by temporary_tablespace;

SELECT * FROM DATABASE_PROPERTIES where PROPERTY_NAME='DEFAULT_TEMP_TABLESPACE';

Changing the default temporary Tablespace

SQL> alter database default temporary tablespace TEMP;

Database altered.

To add tempfile to Temp Tablespace

alter tablespace  temp  add tempfile '&tempfilepath' size 1800M;

alter tablespace temp add tempfile '/m001/oradata/SID/temp02.dbf' size 1000m;

alter tablespace TEMP add tempfile '/SID/oradata/data02/temp04.dbf' size 1800M autoextend on maxsize 1800M;

To resize the  tempfile in Temp Tablespace

alter database tempfile '/u02/oradata/TESTDB/temp01.dbf' resize 250M

alter database tempfile '/SID/oradata/data02/temp12.dbf' autoextend on maxsize 1800M;

alter tablespace TEMP add tempfile '/SID/oradata/data02/temp05.dbf' size 1800m reuse;

To find Sort Segment Usage by Users

select username,sum(extents) "Extents",sum(blocks) "Block"
from v$sort_usage
group by username;

To find Sort Segment Usage by a particular User

SELECT s.username,s.sid,s.serial#,u.tablespace, u.contents, u.extents, u.blocks
FROM v$session s, v$sort_usage u
WHERE s.saddr=u.session_addr
order by u.blocks desc;

To find Total Free space in Temp Tablespace

select 'FreeSpace  ' || (free_blocks*8)/1024/1024 ||' GB'  from v$sort_segment where tablespace_name='TEMP';

select tablespace_name , (free_blocks*8)/1024/1024  FreeSpaceInGB,
(used_blocks*8)/1024/1024  UsedSpaceInGB,
(total_blocks*8)/1024/1024  TotalSpaceInGB
from v$sort_segment where tablespace_name like '%TEMP%'

To find  Total Space Allocated for Temp Tablespace

select 'TotalSpace ' || (sum(blocks)*8)/1024/1024 ||' GB'  from dba_temp_files where tablespace_name='TEMP';

Get 10 sessions with largest temp usage

cursor bigtemp_sids is
select * from (
select s.sid,
s.status,
s.sql_hash_value sesshash,
u.SQLHASH sorthash,
s.username,
u.tablespace,
sum(u.blocks*p.value/1024/1024) mbused ,
sum(u.extents) noexts,
nvl(s.module,s.program) proginfo,
floor(last_call_et/3600)||':'||
floor(mod(last_call_et,3600)/60)||':'||
mod(mod(last_call_et,3600),60) lastcallet
from v$sort_usage u,
v$session s,
v$parameter p
where u.session_addr = s.saddr
and p.name = 'db_block_size'
group by s.sid,s.status,s.sql_hash_value,u.sqlhash,s.username,u.tablespace,
nvl(s.module,s.program),
floor(last_call_et/3600)||':'||
floor(mod(last_call_et,3600)/60)||':'||
mod(mod(last_call_et,3600),60)
order by 7 desc,3)
where rownum < 11;

Displays the amount of IO for each tempfile

SELECT SUBSTR(t.name,1,50) AS file_name,
f.phyblkrd AS blocks_read,
f.phyblkwrt AS blocks_written,
f.phyblkrd + f.phyblkwrt AS total_io
FROM   v$tempstat f,v$tempfile t
WHERE  t.file# = f.file#
ORDER BY f.phyblkrd + f.phyblkwrt DESC;

select * from (SELECT u.tablespace, s.username, s.sid, s.serial#, s.logon_time, program, u.extents, ((u.blocks*8)/1024) as MB,
i.inst_id,i.host_name
FROM gv$session s, gv$sort_usage u ,gv$instance i
WHERE s.saddr=u.session_addr and u.inst_id=i.inst_id  order by MB DESC) a where rownum<10;

Check for ORA-1652

show parameter background

cd <background dump destination>

ls -ltr|tail

view <alert log file name>

shift + G ---> to get the tail end...

?ORA-1652 ---- to search of the error...

shift + N ---- to step for next reported error...

I used these queries to check some settings:

-- List all database files and their tablespaces:
select  file_name, tablespace_name, status
,bytes   /1000000  as MB
,maxbytes/1000000  as MB_max
from dba_data_files ;

-- What temporary tablespace is each user using?:
select username, temporary_tablespace, default_tablespace from dba_users ;

-- List all tablespaces and some settings:
select tablespace_name, status, contents, extent_management
from dba_tablespaces ;

TABLESPACE_NAME                CONTENTS  EXTENT_MAN STATUS
------------------------------ --------- ---------- ---------
SYSTEM                         PERMANENT DICTIONARY ONLINE
TOOLS                          PERMANENT DICTIONARY ONLINE
TEMP                           TEMPORARY DICTIONARY OFFLINE
TMP                            TEMPORARY LOCAL      ONLINE

Now, the above query and the storage clause of the old 'create tablespace TEMP' command seem to tell us the tablespace only allows temporary objects, so it should be safe to assume that no one created any tables or other permanent objects in TEMP by mistake, as I think Oracle would prevent that. However, just to be absolutely certain, I decided to double-check. Checking for any tables in the tablespace is very easy:

-- Show number of tables in the TEMP tablespace - SHOULD be 0:
select count(*)  from dba_all_tables
where tablespace_name = 'TEMP' ;

Checking for any other objects (views, indexes, triggers, pl/sql, etc.) is trickier, but this query seems to work correctly - note that you'll probably need to connect internal in order to see the sys_objects view:

-- Shows all objects which exist in the TEMP tablespace - should get
-- NO rows for this:
column owner        format a20
column object_type  format a30
column object_name  format a40
select
o.owner  ,o.object_name
,o.object_type
from sys_objects s
,dba_objects o
,dba_data_files df
where df.file_id = s.header_file
and o.object_id = s.object_id
and df.tablespace_name = 'TEMP' ;

Identifying WHO is currently using TEMP Segments

10g onwards

SELECT sysdate,a.username, a.sid, a.serial#, a.osuser, (b.blocks*d.block_size)/1048576 MB_used, c.sql_text
FROM v$session a, v$tempseg_usage b, v$sqlarea c,
     (select block_size from dba_tablespaces where tablespace_name='TEMP') d
    WHERE b.tablespace = 'TEMP'
    and a.saddr = b.session_addr
    AND c.address= a.sql_address
    AND c.hash_value = a.sql_hash_value
    AND (b.blocks*d.block_size)/1048576 > 1024
    ORDER BY b.tablespace, 6 desc;


------------------------------------11g

select TABLESPACE_NAME , tablespace_size/1024/1024 totalMB, free_spAce/1024/1024 Just_FreeSpaceMB, (TABLESPACE_SIZE-FREE_SPACE)/1024/1024 FreeMb, (TABLESPACE_SIZE-ALLOCATED_SPACE)/1024/1024 AllocSize from dba_temp_free_space ;

SELECT TABLESPACE_NAME, FILE_ID, BYTES_USED, BYTES_FREE FROM V$TEMP_SPACE_HEADER;

DBA_TEMP_FREE_SPACE displays temporary space usage information at tablespace level.
Column Datatype NULL Description
TABLESPACE_NAME VARCHAR2(30) NOT NULL Name of the tablespace
TABLESPACE_SIZE NUMBER Total size of the tablespace, in bytes
ALLOCATED_SPACE NUMBER Total allocated space, in bytes, including space that is currently allocated and used and space that is currently allocated and available for reuse
FREE_SPACE NUMBER Total free space available, in bytes, including space that is currently allocated and available for reuse and space that is currently unallocated


Blocking Session Lockwait Best

SELECT TO_CHAR(sysdate, 'DD-MON-YYYY HH24:MI:SS')
|| ' User '
||s1.username
|| '@'
|| s1.machine
|| ' ( SID= '
|| s1.sid
|| ' ) with the statement: '
|| sqlt2.sql_text
||' is blocking the SQL statement on '
|| s2.username
|| '@'
|| s2.machine
|| ' ( SID='
|| s2.sid
|| ' ) blocked SQL -> '
||sqlt1.sql_text AS blocking_status
FROM v$lock l1, v$session s1, v$lock l2 ,
v$session s2,v$sql sqlt1, v$sql sqlt2
WHERE s1.sid =l1.sid
AND s2.sid =l2.sid AND sqlt1.sql_id= s2.sql_id AND sqlt2.sql_id= s1.prev_sql_id AND l1.BLOCK =1
AND l2.request > 0 AND l1.id1 = l2.id1 AND l2.id2 = l2.id2;

Tuesday, September 25, 2012

expdp procedure in 11g


 1) create directory export_auto as 'd:\expdp1213';

 create user dba_export_user identified by test123;

grant connect, create database link, resource, create view to dba_export_user;
grant unlimited tablespace to dba_export_user;
grant exp_full_database to dba_export_user;
grant read,write on directory export_auto to dba_export_user;
grant execute on dbms_flashback to dba_export_user;
grant create table to dba_export_user;
grant FLASHBACK ANY TABLE to dba_export_user;


2)
CREATE OR REPLACE PROCEDURE dba_export_user.start_export
IS
   hdl_job        NUMBER;
   l_cur_scn      NUMBER;
   l_job_state    VARCHAR2 (20);
   l_status       SYS.ku$_status1010;
   l_job_status   SYS.ku$_jobstatus1010;
BEGIN

 begin
    execute immediate 'drop table  dba_export_user.AUTO_EXPORT';
    exception when others then null;
   end;

   hdl_job := DBMS_DATAPUMP.OPEN ( operation => 'EXPORT', job_mode => 'FULL', job_name => 'AUTO_EXPORT' );
 
   DBMS_DATAPUMP.add_file (handle => hdl_job,filename => 'EXPDP1213.dmp',directory => 'EXPORT_AUTO',filetype => DBMS_DATAPUMP.ku$_file_type_dump_file,reusefile => 1);
                         
   DBMS_DATAPUMP.add_file (handle => hdl_job,filename => 'export.log',DIRECTORY => 'EXPORT_AUTO',filetype => DBMS_DATAPUMP.ku$_file_type_log_file,reusefile => 1);
                     
   DBMS_DATAPUMP.start_job (handle => hdl_job);
 
   DBMS_DATAPUMP.wait_for_job (handle => hdl_job, job_state => l_job_state);
 
   DBMS_OUTPUT.put_line ('Job exited with status:' || l_job_state);

  DBMS_DATAPUMP.detach(handle => hdl_job);

END;
/


3) Change the time, Date

begin
 dbms_scheduler.create_job(
      job_name => 'EXPORT_JOB'
     ,job_type => 'STORED_PROCEDURE'
     ,job_action => 'dba_export_user.start_export'
     ,start_date => '08-FEB-12 06.02.00.00 PM ASIA/CALCUTTA'
       ,repeat_interval => 'FREQ=DAILY; BYDAY=MON,TUE,WED,THU,FRI,SAT,SUN;'
     ,enabled => TRUE
     ,comments => 'EXPORT_DATABASE_JOB');
end;
/

EXEC  dbms_scheduler.run_job('EXPORT_JOB');

Friday, September 21, 2012

RMAN Block Media Recovery


From Oracle 9i onwards you can use RMAN to recover only blocks while database is up and running.
This could possibly save hours and hours of recovery time as a full database restore  is not necessary.
Error reported by user pointing to block corruption.

 POPULATE_MACSDATA - ORA-01578: ORACLE data block corrupted  (file # 48, block # 142713)
ORA-01110: data file 48: '/hqlinux08db06/ORACLE/macsl/MACSDAT_2006_06.dbf'
ORA-02063: preceding 2 lines from MODSL_MACSL_LINK
File name : /hqlinux08db06/ORACLE/macsl/MACSDAT_2006_06.dbf

Check first if the there is only one(few) blocks corrupted or most of the blocks are corrupted.

macsl:/opt/oracle/admin/macsl/bdump>
Issue command below at UNIX prompt.

dbv file=/hqlinux08db06/ORACLE/macsl/MACSDAT_2006_06.dbf BLOCKSIZE=8192 LOGFILE=test.log

DBV-00200: Block, dba 201469305, already marked corrupted

SQL> Select * from v$database_block_corruption;

You will get block number corrupt.
Ex: block 142713.

After that LOGIN TO RMAN.

rman target / catalog rman10/rman10@rman10p
RMAN> BLOCKRECOVER DATAFILE 48 BLOCK 142713;

V$database_block_corruption is the view to check the list of corrupted blocks.

If you have multiple block list as corrupt, You can use single command to recover them.

RMAN> BLOCKRECOVER corruption list;

Thursday, September 20, 2012

Table level Recovery using Flashback Table



---------------------------------------------------Recover Dropped Table from Recyclebin using Flashback Table-------------------------

Oracle Flashback Table enables you to restore a table to its state as of a previous point in time. It provides a fast, online solution for recovering a table that has been accidentally modified or deleted by a user or application. In many

cases, Oracle Flashback Table eliminates the need for you to perform more complicated point-in-time recovery operations.

Oracle Flashback Table:

Restores all data in a specified table to a previous point in time described by a timestamp or SCN.

Performs the restore operation online.

Automatically maintains all of the table attributes, such as indexes, triggers, and constraints that are necessary for an application to function with the flashed-back table.

Maintains any remote state in a distributed environment. For example, all of the table modifications required by replication if a replicated table is flashed back.

Maintains data integrity as specified by constraints. Tables are flashed back provided none of the table constraints are violated. This includes any referential integrity constraints specified between a table included in the FLASHBACK

TABLE statement and another table that is not included in the FLASHBACK TABLE statement.

Even after a flashback operation, the data in the original table is not lost. You can later revert to the original state.

FLASHBACK TABLE <table_name> TO BEFORE DROP;

Some other variations of the flashback database command include.

FLASHBACK DATABASE TO TIMESTAMP my_date;
FLASHBACK DATABASE TO BEFORE TIMESTAMP my_date;
FLASHBACK DATABASE TO SCN my_scn;
FLASHBACK DATABASE TO BEFORE SCN my_scn;

--------------------------------------------------Recover deleted Table Data from Recyclebin using Flashback Table---------------------

On Oracle Database 11g (10gR2...), we can rewind one or more tables back to their contents at a previous time without affecting other database objects.

Before we use Flashback Table, We must enable row movement on the table. because rowids will change after the flashback.

Example: Flashback the table back to previous time using SCN


select count(*) from LDBO.test;
COUNT(*)
----------
68781

SQL> SELECT CURRENT_SCN FROM V$DATABASE;

CURRENT_SCN
-----------
1584494

SQL> delete from LDBO.test where rownum <= 50000;

50000 rows deleted.

SQL> commit;

Commit complete.

SQL> select count(*) from LDBO.test;

COUNT(*)
----------
18781

SQL> SELECT CURRENT_SCN FROM V$DATABASE;

CURRENT_SCN
-----------
1587106

Enable row movement:

SQL> alter table LDBO.test enable row movement;

Table altered.

SQL> FLASHBACK TABLE LDBO.test to scn 1584494;

Flashback complete.

SQL> select count(*) from LDBO.test;


QL> alter table LDBO.test disable row movement;

Table altered.


We can rewind the table back to previous time using timestamp:

SQL> alter session set nls_date_format='YYYY/MM/DD HH24:MI:SS';

Session altered.

SQL> select sysdate from dual;

SYSDATE
-------------------
2009/08/30 17:01:09

SQL> delete from LDBO.test ;

68781 rows deleted.

SQL> commit;

Commit complete.

SQL> select sysdate from dual;

SYSDATE
-------------------
2009/08/30 17:03:18

SQL> select count(*) from LDBO.test;

COUNT(*)
----------
0

SQL> alter table LDBO.test enable row movement;

Table altered.

SQL> flashback table LDBO.test to timestamp TO_TIMESTAMP('2009/08/30 17:01:09','YYYY/MM/DD HH24:MI:SS');

Flashback complete.

SQL> select count(*) from LDBO.test;

COUNT(*)
----------
68781

--------------------------------------------------------------------------------------------Flashback Table recover table to different table----------------------

FLASHBACK TABLE test TO BEFORE DROP RENAME TO test2;

flashback table LDBO.test to timestamp TO_TIMESTAMP('2009/08/30 17:01:09','YYYY/MM/DD HH24:MI:SS') RENAME TO test2;




Friday, September 14, 2012

11g Active Data Guard - enabling Real-Time Query


Active Data Guard is a good new feature in 11g (although requires a license) which enables us to query the Standby database while redo logs are being applied to it. In earlier releases, we had to stop the log apply, open the database in read only mode and then start the log apply again when the database was taken out of the read only mode.
With Oracle 11g Active Data Guard, we can make use of our standby site to offload reporting and query type applications while at the same time not compromising on the high availability aspect.
How do we enable Active Data Guard?
If we are not using the Data Guard Broker, we need to open the standby database, set it in read only mode and then start the managed recovery as shown below.
SQL> shutdown immediate;
Database closed.
Database dismounted.
ORACLE instance shut down.
SQL> startup
ORACLE instance started.
Total System Global Area 1069252608 bytes
Fixed Size 2154936 bytes
Variable Size 847257160 bytes
Database Buffers 213909504 bytes
Redo Buffers 5931008 bytes
Database mounted.
Database opened.
SQL> recover managed standby database using current logfile disconnect;
Media recovery complete.
If we are using the Data Guard Broker CLI, DGMGRL, the procedure is a bit different and is not very clearly explained in the documentation.
You need to stop redo apply first via the SET STATE dgmgrl command, then from a SQL*PLUS session, open the database in read only mode, and then back again from dgmgrl via set SET STATE command, start the redo apply again.
Stop redo apply with the following command from Data Guard Broker CLI
DGMGRL> EDIT DATABASE ‘PRODDB’ SET STATE=’APPLY-OFF’;
Open standby read-only via SQL*Plus
SQL> alter database open read only;
Restart redo apply via broker CLI
DGMGRL> EDIT DATABASE ‘PRODDB’ SET STATE=’APPLY-ON’;
I tried to run the same only via DGMGRL and got this error:
DGMGRL> edit database PRODDB set state=”APPLY-OFF”;
Succeeded.
DGMGRL> edit database PRODDB set state=”READ ONLY”;
Error: ORA-16516: current state is invalid for the attempted operation
After we have enabled the Real-Time Query feature, we can confirm the same via the DGMGRL command – SHOW DATABASE
DGMGRL> show database verbose PRODDB_DR
Database – PRODDB_DR
Role: PHYSICAL STANDBY
Intended State: APPLY-ON
Transport Lag: 0 seconds
Apply Lag: 0 seconds
Real Time Query: ON
Note:
Even though we have enabled Real-Time Query feature, if we go to Data Guard page via the Enterprise Manager Grid Control GUI, it will show that Real-Time Query is in a Disabled state.
This is apparently a bug which applies to OEM Grid Control 10.2.0.1 to 10.2.0.5 with a 11.2 target database.
Bug 7633734: DG ADMIN PAGE REAL TIME QUERY SHOWS DISABLED WHEN ENABLED FOR 11.2 DATABASES

RMAN Recovery Scenarios


RMAN Backup and Recovery Scenarios


RMAN Backup and Recovery Scenarios

 

Complete Closed Database Recovery. System tablespace is missing

If the system tablespace is missing or corrupted the database cannot be started up so a complete closed database recovery must be performed.
Pre requisites: A closed or open database backup and archived logs.
1. Use OS commands to restore the missing or corrupted system datafile to its original location, ie:
cp -p /usr/backup/RMAN/system01.dbf  /usr/oradata/u01/IASDB/system01.dbf
2. startup mount;
3. recover datafile 1;
4. alter database open;

Complete Open Database Recovery. Non system tablespace is missing

If a non system tablespace is missing or corrupted while the database is open, recovery can be performed while the database remain open.
Pre requisites: A closed or open database backup and archived logs.
1. Use OS commands to restore the missing or corrupted datafile to its original location, ie:
cp -p /usr/backup/RMAN/user01.dbf /usr/oradata/u01/IASDB/user01.dbf
2. alter tablespace <tablespace_name> offline immediate;
3. recover tablespace <tablespace_name>;
4. alter tablespace <tablespace_name> online;

Complete Open Database Recovery (when the database is initially closed).Non system tablespace is missing

If a non system tablespace is missing or corrupted and the database crashed,recovery can be performed after the database is open.
Pre requisites: A closed or open database backup and archived logs.
1.   startup; (you will get ora-1157 ora-1110 and the name of the missing datafile, the database will remain mounted)
2.   Use OS commands to restore the missing or corrupted datafile to its original location, ie:
cp -p /usr/backup/RMAN/user01.dbf /usr/oradata/u01/IASDB/user01.dbf
3.   alter database datafile 6 offline; (tablespace cannot be used because the database is not open)
4.   alter database open;
5.   recover datafile 6;
6.   alter tablespace <tablespace_name> online;

Recovery of a Missing Datafile that has no backups (database is open).

If a non system datafile that was not backed up since the last backup is missing,recovery can be performed if all archived logs since the creation of the missing datafile exist.
Pre requisites: All relevant archived logs.
1.   alter tablespace <tablespace_name> offline immediate;
2.   alter database create datafile ‘/user/oradata/u01/IASDB/newdata01.dbf’;
3.   recover tablespace <tablespace_name>;
4.   alter tablespace <tablespace_name> online;
If the create datafile command needs to be executed to place the datafile on a location different than the original use:
alter database create datafile ‘/user/oradata/u01/IASDB/newdata01.dbf’ as ‘/user/oradata/u02/IASDB/newdata01.dbf’

Restore and Recovery of a Datafile to a different location.

If a non system datafile is missing and its original location not available, restore can be made to a different location and recovery performed.
Pre requisites: All relevant archived logs.
1.    Use OS commands to restore the missing or corrupted datafile to the new location, ie:
cp -p /usr/backup/RMAN/user01.dbf /usr/oradata/u02/IASDB/user01.dbf
2.    alter tablespace <tablespace_name> offline immediate;
3.    alter tablespace <tablespace_name> rename datafile ‘/user/oradata/u01/IASDB/user01.dbf’ to ‘/user/oradata/u02/IASDB/user01.dbf’;
4.    recover tablespace <tablespace_name>;
5.    alter tablespace <tablespace_name> online;

Control File Recovery

Always multiplex your controlfiles. Controlfiles are missing, database crash.
Pre requisites: A backup of your controlfile and all relevant archived logs.
1.    startup; (you get ora-205, missing controlfile, instance start but database is not mounted)
2.    Use OS commands to restore the missing controlfile to its original location:
cp -p /usr/backup/RMAN/control01.dbf /usr/oradata/u01/IASDB/control01.dbf
cp -p /usr/backup/RMAN/control02.dbf /usr/oradata/u01/IASDB/control02.dbf
3.    alter database mount;
4.    recover automatic database using backup controlfile;
5.    alter database open resetlogs;
6.    make a new complete backup, as the database is open in a new incarnation and previous archived log are not relevant.

Incomplete Recovery, Until Time/Sequence/Cancel

Incomplete recovery may be necessaire when an archived log is missing, so recovery can only be made until the previous sequence, or when an important object was dropped, and recovery needs to be made until before the object was dropped.
Pre requisites: A closed or open database backup and archived logs, the time or sequence that the ‘until’ recovery needs to be performed.
1.  If the database is open, shutdown abort
2.  Use OS commands to restore all datafiles to its original locations:
cp -p /usr/backup/RMAN/u01/*.dbf /usr/oradata/u01/IASDB/
cp -p /usr/backup/RMAN/u02/*.dbf /usr/oradata/u01/IASDB/
cp -p /usr/backup/RMAN/u03/*.dbf /usr/oradata/u01/IASDB/
cp -p /usr/backup/RMAN/u04/*.dbf /usr/oradata/u01/IASDB/
etc…
3.  startup mount;
4.  recover automatic database until time ’2004-03-31:14:40:45′;
5.  alter database open resetlogs;
6.  make a new complete backup, as the database is open in a new incarnation and previous archived log are not relevant.Alternatively you   may use instead of until time, until sequence or until cancel:
recover automatic database until sequence 120 thread 1; OR
recover database until cancel;

Rman Recovery Scenarios

Rman recovery scenarios require that the database is in archive log mode, and that backups of datafiles, control files and archived redolog files are made using Rman. Incremental Rman backups may be used also.
Rman can be used with the repository installed on the archivelog, or with a recovery catalog that may be installed in the same or other database.
Configuration and operation recommendations:
Set the parameter controlfile autobackup to ON to have with each backup a
controlfile backup also:
configure controlfile autobackup on;
set the parameter retention policy to the recovery window you want to have,
ie redundancy 2 will keep the last two backups available, after executing delete obsolete commands:
configure retention policy to redundancy 2;
Execute your full backups with the option ‘plus archivelogs’ to include your archivelogs with every backup:
backup database plus archivelog;
Perform daily maintenance routines to maintain on your backup directory the number of backups you need only:
crosscheck backup;
crosscheck archivelog all;
delete noprompt obsolete backup;
To work with Rman and a database based catalog follow these steps:
1. sqlplus /
2. create tablespace repcat;
3. create user rmuser identified by rmuser default tablespace repcat temporary tablespace temp;
4. grant connect, resource, recovery_catalog_owner to rmuser
5. exit
6. rman catalog rmuser/rmuser          # connect to rman catalog as the rmuser
7. create catalog                     # create the catalog
8. connect target /                   #

Complete Closed Database Recovery. System tablespace is missing

In this case complete recovery is performed, only the system tablespace is missing,so the database can be opened without reseting the redologs.
1.  rman target /
2.  startup mount;
3.  restore database;
4.  recover database;
5.  alter database open;

Complete Open Database Recovery. Non system tablespace is missing,database is up

1.   rman target /
2.   sql ‘alter tablespace <tablespace_name> offline immediate’;
3.   restore datafile 3;
4.   recover datafile 3;
5.   sql ‘alter tablespace <tablespace_name> online’;

Complete Open Database Recovery (when the database is initially closed).Non system tablespace is missing

A user datafile is reported missing when tryin to startup the database. The datafile can be turned offline and the database started up. Restore and recovery are performed using Rman. After recovery is performed the datafile can be turned online again.
1.    sqlplus /nolog
2.    connect / as sysdba
3.    startup mount
4.    alter database datafile ‘<datafile_name>’ offline;
5.    alter database open;
6.    exit;
7.    rman target /
8.    restore datafile ‘<datafile_name>’;
9.    recover datafile ‘<datafile_name>’;
10.   sql ‘alter tablespace <tablespace_name> online’;

Recovery of a Datafile that has no backups (database is up).

If a non system datafile that was not backed up since the last backup is missing,recovery can be performed if all archived logs since the creation of the missing datafile exist. Since the database is up you can check the tablespace name and put it offline. The option offline immediate is used to avoid that the update of the datafile header.
Pre requisites: All relevant archived logs.
1.    sqlplus ‘/ as sysdba’
2.    alter tablespace <tablespace_name> offline immediate;
3.    alter database create datafile ‘/user/oradata/u01/IASDB/newdata01.dbf;
4.    exit
5.    rman target /
6.    recover tablespace <tablespace_name>;
7.    sql ‘alter tablespace <tablespace_name> online’;
If the create datafile command needs to be executed to place the datafile on a location different than the original use:
alter database create datafile ‘/user/oradata/u01/IASDB/newdata01.dbf’ as ‘/user/oradata/u02/IASDB/newdata01.dbf’

Restore and Recovery of a Datafile to a different location. Database is up.

If a non system datafile is missing and its original location not available, restore can be made to a different location and recovery performed.
Pre requisites: All relevant archived logs, complete cold or hot backup.
1.    Use OS commands to restore the missing or corrupted datafile to the new location, ie:
cp -p /usr/backup/RMAN/user01.dbf /usr/oradata/u02/IASDB/user01.dbf
2.    alter tablespace <tablespace_name> offline immediate;
3.    alter tablespace <tablespace_name> rename datafile ‘/user/oradata/u01/IASDB/user01.dbf’ to ‘/user/oradata/u02/IASDB/user01.dbf’;
4.    rman target /
5.    recover tablespace <tablespace_name>;
6.    sql ‘alter tablespace <tablespace_name> online’;

Control File Recovery

Always multiplex your controlfiles. If you loose only one controlfile you can replace it with the one you have in place, and startup the Database. If both controlfiles are missing, the database will crash.
Pre requisites: A backup of your controlfile and all relevant archived logs. When using Rman alway set configuration parameter autobackup of controlfile to ON. You will need the dbid to restore the controlfile, get it from the name of the backed up controlfile.It is the number following the ‘c-’ at the start of the name.
1.   rman target /
2.   set dbid <dbid#>
3.   startup nomount;
4.   restore controlfile from autobackup;
5.   alter database mount;
6.   recover database;
7.   alter database open resetlogs;
8.   make a new complete backup, as the database is open in a new incarnation and previous archived log are not relevant.

Incomplete Recovery, Until Time/Sequence/Cancel

Incomplete recovery may be necessaire when the database crash and needs to be recovered, and in the recovery process you find that an archived log is missing. In this case recovery can only be made until the sequence before the one that is missing.
Another scenario for incomplete recovery occurs when an important object was dropped or incorrect data was committed on it.
In this case recovery needs to be performed until before the object was dropped.
Pre requisites: A full closed or open database backup and archived logs, the time or sequence that the ‘until’ recovery needs to be performed.
1.   If the database is open, shutdown it to perform full restore.
2.   rman target \
3.   startup mount;
4.   restore database;
5.   recover database until sequence 8 thread 1; # you must pass the thread, if a single instance will always be 1.
6.  alter database open resetlogs;
7.  make a new complete backup, as the database is open in a new incarnation and previous archived log are not relevant.Alternatively you may use instead of until sequence, until time, ie: ’2012-01-04:01:01:10′.

RMAN scenarios


http://itcareershift.com/blog1/2010/11/25/real-life-oracle-dba-scenarios-using-rman-backups-and-troubleshooting-new-oracle-dba-career/
http://docs.oracle.com/cd/B28359_01/backup.111/b28270/rcmadvre.htm
http://www.reachdba.com/showthread.php?453-RMAN-All-major-Restoration-and-Recovery-Scenarios


Note: When database is in open state then we can not delete datafiles from OS level (File is being used by another User)


--------------------------------------------------------------DataFile removed physcially from OS level and no Backup of that datafile------------------------------------

1) rman backup taken 01-01-12
2) add datafile and add some tables and data on 02-01-12
3) remove datafile from OS level on 02-01-12 no backup till now
4) alter tablespace USR offline;
ORA-01116: error in opening database file 11
ORA-27041: unable to open file
Linux-x86_64 Error: 2: No such file or directory
5) alter tablespace drtbs offline immediate;
select TABLESPACE_NAME,STATUS from dba_tablespaces;
6) select file_id, file_name from dba_data_files where Tablespace_name='USR';
7) RMAN TARGET
8) rman > list of backup datafile 11;
9) list backup of datafile 12; ---- no exist because no backup
10) RMAN> restore tablespace USR;
11) RMAN> recover tablespace USR;
select file_id, file_name from dba_data_files where Tablespace_name='USR';


--------------------------------------------------------------------------Loss of Controlfile-----------------------------

1) select name from v$controlfile;
2) remove controlfile physcially from OS level
3) alter tablespace users online;
alter tablespace users online
*
ERROR at line 1:
ORA-00603: ORACLE server session terminated by fatal error

SQL> shutdown abort
ORACLE instance shut down.
SQL> startup nomount;

Since we are not using a RMAN catalog we need to set the DBID

RMAN> set dbid=2415549446;

executing command: SET DBID

Restore the controlfile

RMAN> run {
 restore controlfile from autobackup;
 }

error RMAN-06172 because when check show all; controlfile autoback is not present...also not able to configure again becuase of nomount state

set controlfile autobackup format for device type disk to '/orabkp\%F';
restore controlfile from autobackup;


RMAN> alter database mount;
RMAN> recover database;
SQL> alter database open resetlogs;

-------------------------------------recover and open the database if the archive log required for recovery is miss

SQL> recover database until cancel using backup controlfile;
CANCEL
SQL> alter database open resetlogs;
alter database open resetlogs
*
ERROR at line 1:
ORA-01195: online backup of file 1 needs more recovery to be consistent


1) Set _ALLOW_RESETLOGS_CORRUPTION=TRUE in init.ora file.
2) Startup Mount
3) recover database until cancel using backup controlfile;
4) Alter database open resetlogs.
5) reset undo_management to “manual” in init.ora file.
6) startup database
7) Create new undo tablespace
changed undo_management to “AUTO” and undo_tablespace to “NewTablespace”


------------------------------------------Redo log removed from OS level-----------------------------------

select member from v$Logfile;

rm redo*.log

If one or all of the online redo logfiles are delete then the database hangs and in the alert log file
ARC1: Failed to archive thread 1 sequence 10 (0)

SQL> shutdown immediate;
SQL> startup mount;

SELECT GROUP#,SEQUENCE#,STATUS,FIRST_CHANGE# from v$log;

   GROUP#  SEQUENCE# STATUS           FIRST_CHANGE#
--------- ---------- ---------------- -------------
        1         10 CURRENT             8.6056E+10
        3          9 INACTIVE            8.6056E+10
        2          8 INACTIVE            8.6056E+10

RMAN TARGET /
RMAN> run {
2> set until sequence 10;
3> restore database;
4> recover database;
5>  alter database open resetlogs;
6> }
EXIT

The recovery process creates the online redo logfiles at the operating system level also.
Since we have done an incomplete recover with open resetlogs, we should take a fresh complete backup of the database.

NOTE: Please make sure you remove all the old archived logfiles from the archived area.




------------------------------------------------------Drop tablespace by mistake (drop tablespace test including contents and datafiles;)------Point inTime

DBA realized the mistake;

He will refer alert log for the exact timing when tablespace was dropped.

-------Alert log--------------

Sun Feb  4 10:59:43 2012
drop tablespace test including contents and datafiles
Sun Feb 4 10:59:47 2012
Completed: drop tablespace test including contents and datafiles



SQL> shutdown abort
rman target /

RMAN> RUN
{
STARTUP NOMOUNT
SET UNTIL TIME "TO_DATE ('04-02-07 10:58:00', 'DD-MM-YY HH24:MI:SS')";
RESTORE CONTROLFILE;
ALTER DATABASE MOUNT;
RESTORE DATABASE;
RECOVER DATABASE;
ALTER DATABASE OPEN RESETLOGS;
}

select name from v$tablespace;

-----------------------------------------------------------Complete loss of all database files including SPFILE using RMAN

ls -l
rm *.dbf
ls -l *.dbf
ls: *.dbf: No such file or directory
mv spfileopsdba.ora spfileopsdba.org
ls -lt spfile* *SPFILE REMOVED


Database Details
------------------
Database Name=OPSDBA
Machine Name=ITLINUXDEVBLADE07
DBID=1499754868 (select dbid from v$database)
---------------------

Step 1: RECOVERY OF SPFILE

Create spfile.rcv as:
set dbid= 1499754868
run {
startup nomount force  ;
 };

rman target / catalog rman10/rman10@rman10p cmdfile=spfile.rcv

Now restore the spfile

set dbid=1499754868
run {
allocate channel ch1 type 'sbt_tape' parms 'ENV=(TDPO_OPTFILE=/opt/tivoli/tsm/client/oracle/bin64/tdpo.opsdbad.opt)';
restore spfile ;
release channel ch1 ;
}


Step 2: RESTORE OF CONTROLFILES

Same Steps as spfile with the restore command changed. So the new script is

set dbid=1499754868
run {
allocate channel ch1 type 'sbt_tape' parms 'ENV=(TDPO_OPTFILE=/opt/tivoli/tsm/client/oracle/bin64/tdpo.opsdbad.opt)';
restore controlfile ;
release channel ch1 ;
}

Step 3: RESTORE OF DATABASE
SQL> conn sys as sysdba
SQL> alter database mount;

Now get the log sequence number of the database from the catalog database:

select sequence# from rc_backup_redolog where db_name=’OPSDBA’;

RMAN> run {
2> allocate channel ch1 type 'sbt_tape' parms 'ENV=(TDPO_OPTFILE=/opt/tivoli/tsm/client/oracle/bin64/tdpo.opsdbad.opt)';
3> restore database ;
4> recover database until logseq=6; -- GOT FROM THE ABOVE QUERY
5> release channel ch1 ;
6> }
7>


Step 4: alter database open resetlogs;



--------------------------- SYSTEM / SYSAUX / UNDO tablespace is missing

In this case complete recovery is performed, only the system tablespace is missing, so the database can be opened without resetlogs option.

$ rman target /
RMAN> startup mount;
RMAN> restore tablespace SYSTEM;
RMAN> recover tablespace SYSTEM;
RMAN> alter database open;

$ rman target /
RMAN> startup mount;
RMAN> restore tablespace SYSAUX;
RMAN> recover tablespace SYSAUX;
RMAN> alter database open;



------------------------------Non system tablespace is missing, database is up

$ rman target /
RMAN> sql ‘alter tablespace <tbs> offline immediate’ ;
RMAN> restore tablespace <tbs> ;
RMAN> recover tablespace <tbs> ;
RMAN> sql ‘alter tablespace <tbs> online’ ;

To restore/recover only datafile(s)
$ rman target /

RMAN>. sql 'alter database datafile <file#> offline';
RMAN> restore datafile <file#>;
RMAN> recover datafile <file#>;
RMAN> sql 'alter database datafile <file#> online' ;

-------------------------------Non system tablespace is missing,database is closed
sqlplus “/ as sysdba “
startup mount
alter database datafile <file#> offline;
alter database open;
exit;

$rman target /
RMAN> restore datafile <file#>;
RMAN> recover datafile <file#>;
RMAN> sql 'alter tablespace <tablespace_name> online';


-----------------------restore a tablespace to a new location
 rman target / catalog rman/rman@rcat
run {
allocate channel ch1 type disk;
sql 'ALTER TABLESPACE USERS OFFLINE IMMEDIATE';
set newname for datafile '/disk1/oracle/users_1.dbf' to '/disk2/oracle/users_1.dbf';
restore tablespace users;
# make the control file recognize the restored file as current
switch datafile all;
}

RMAN> recover tablespace USERS;
RMAN> sql 'alter tablespace USERS online';

-------------------Recovery of a Datafile that has no backups (database is up)
If a non system datafile that was not backed up since the last backup, is missing, recovery can be performed if all archived logs since the creation of the missing datafile exist.

Pre requisites: All relevant archived logs.

$ rman target /
RMAN> sql ‘alter database datafile <file#> offline’;
RMAN> restore datafile <file#> ;
-- no need to create a blank file, restore command takes care of that.
RMAN> recover datafile <file#>;
RMAN> sql 'alter database datafile <file#> online';

-------------------------------Recovering After the Loss of All Members of an Online Redo Log Group

If a media failure damages all members of an online redo log group, then different scenarios can occur depending on the type of online redo log group affected by the failure and the archiving mode of the database.
If the damaged log group is inactive, then it is not needed for crash recovery; if it is active, then it is needed for crash recovery.
SQL> startup mount

Case-1 If the group is INACTIVE
Then it is not needed for crash recovery
Clear the archived or unarchived group. (For archive status, check in v$log)

1.1 Clearing Inactive, Archived Redo

alter database clear logfile group 1 ;
alter database open ;

1.2 Clearing Inactive, Not-Yet-Archived Redo

alter database clear unarchived logfile group 1 ;
OR
(If there is an offline datafile that requires the cleared log to bring it online, then the keywords UNRECOVERABLE DATAFILE are required. The datafile and its entire tablespace have to be dropped because the redo necessary to bring it online is being cleared, and there is no copy of it. )

alter database clear unarchived logfile group 1 unrecoverable datafile;

Take a complete backup of database.

And now open database:
alter database open ;


Case-2 If the group is ACTIVE

Restore backup and perform an incomplete recovery.
And open database using resetlogs
alter database open resetlogs;

Case-3 If the group is CURRENT

Restore backup and perform an incomplete recovery.
And open database using resetlogs
alter database open resetlogs;


--------------------------
1) OPEN REDO01.LOG (INACTIVE) AND EDIT AND CORRUPT IT

SQL> ALTER SYSTEM SWITCH LOGFILE; -------HANG
alter database clear logfile group 1 ;

ORA-00350: log 1 of instance rkangel (thread 1) needs to be archived
ORA-00312: online log 1 thread 1: 'G:\RKANGEL\REDO01.LOG'

SQL> SHUT IMMEDIATE
SQL> STARTUP MOUNT
SQL> ALTER DATABASE CLEAR UNARCHIVED LOGFILE GROUP 1;
SQL> ALTER DATABASE OPEN;
SQL> ALTER SYSTEM SWITCH LOGFILE;
SQL> ALTER SYSTEM SWITCH LOGFILE;
SQL> ALTER SYSTEM SWITCH LOGFILE;

-------------2) OPEN REDO02.LOG (ACTIVE) AND EDIT AND CORRUPT IT
SQL> ALTER SYSTEM SWITCH LOGFILE; -------HANG
ERROR at line 1:
ORA-03113: end-of-file on communication channel

SQL> STARTUP
ORACLE instance started.

Total System Global Area 6413680640 bytes
Fixed Size                  2267184 bytes
Variable Size            4563404752 bytes
Database Buffers         1828716544 bytes
Redo Buffers               19292160 bytes
Database mounted.
ORA-00313: open failed for members of log group 2 of thread 1
ORA-00312: online log 2 thread 1: 'G:\RKANGEL\REDO02.LOG'
ORA-27046: file size is not a multiple of logical block size
OSD-04012: file size mismatch (OS 52429318)

ALTER DATABASE CLEAR LOGFILE GROUP 2;
ALTER DATABASE CLEAR UNARCHIVED LOGFILE GROUP 1;
alter database clear logfile group 2 unrecoverable datafile;
*
ERROR at line 1:
ORA-01624: log 2 needed for crash recovery of instance rkangel (thread 1)
ORA-00312: online log 2 thread 1: 'G:\RKANGEL\REDO02.LOG'


-----note: For ACTIVE or CURRENT logfile
Restore backup and perform an incomplete recovery.
And open database using resetlogs
alter database open resetlogs;


1) Set _ALLOW_RESETLOGS_CORRUPTION=TRUE in init.ora file.
2) Startup Mount
3) recover database until cancel using backup controlfile;
4) Alter database open resetlogs.
5) reset undo_management to “manual” in init.ora file.
6) startup database
7) Create new undo tablespace
changed undo_management to “AUTO” and undo_tablespace to “NewTablespace”



--------------------------------------Recovering a NOARCHIVELOG Database
Restore of a database running in NOARCHIVELOG mode is similar to restore of a database in ARCHIVELOG mode. The main differences are:

Only consistent backups can be used in restoring a database in NOARCHIVELOG mode.

Media recovery is not possible because no archived redo logs exist.

When recovering a NOARCHIVELOG database, specify the NOREDO option on the RECOVER command to indicate that RMAN should not attempt to apply archived redo logs.



----------------------------------------------------------------Remove Temporary datafile from OS level---------------------------------

shut immediate
Remove Temporary datafile from OS level
startup
auotmatically create temp

shut immediate
startup mount
Remove Temporary datafile from OS level
alter database open;
auotmatically create temp


----------------------------------------------------------------Remove UNDO datafile from OS level----------------------------------------

shut immediate
startup mount
Remove UNDO datafile from OS level
alter database open;

ERROR at line 1:
ORA-01157: cannot identify/lock data file 3 - see DBWR trace file
ORA-01110: data file 3: 'G:\RKANGEL\UNDOTBS01.ORA'

RMAN> restore tablespace UNDOTBS1;
RMAN> recover tablespace UNDOTBS1;
RMAN> alter database open;


----------------------------------------How to recover dropped / deleted table using RMAN backup----------------------

restore backup on to the UAT machine
export the table from UAT
import into LIVE

1) incomplete recovery ( just before to the drop table) can recover your table from RMAN backup.
or
2) You can recover /duplcate the database to another database with RMAN backup
Export the concerned table from the restored/duplicated database to the database you want.

3) use flashback (in oracle 10g) for indivisual table recovery purpose.
Oracle 10g makes life easier with the ability to recover a dropped table similar to recovering a file from a Windows Recycle Bin.
And in case if this on 10g,
Eg: You dropped the DEPT table, which belongs to the USER_DATA tablespace
You can use the following command to recover a dropped table:

FLASHBACK TABLE <table_name> TO BEFORE DROP;



4) RMAN TSPITR is most useful for recovering the following:
An erroneous DROP TABLE or TRUNCATE TABLE statement
A table that has become logically corrupted
An incorrect batch job or other DML statement that has affected only a subset of the database
A logical schema to a point different from the rest of the physical database when multiple schemas exist in separate tablespaces of one physical database

--------------------------------------------------------Point in time recovery using RMAN (until a log sequence number) ----------------delete some data from table by mistake

Someone delete all data from a table at 1:47 PM (delete from myobjects) SELECT * FROM DBA_AUDIT_TRAIL;

windows dir d:\archive
20/09/2012  01:44 PM             1,024 ARC0000000010_0794497245.0001
20/09/2012  01:47 PM        41,461,248 ARC0000000011_0794497245.0001


archive log list
Database log mode              Archive Mode
Automatic archival             Enabled
Archive destination            /u02/ORACLE/opsdba/arch
Oldest online log sequence     21
Next log sequence to archive   23
Current log sequence           23
--Note the current log sequence number (22)

We need to determine the log sequence we need to recover until
select sequence#,first_change#, to_char(first_time,'HH24:MI:SS') from v$log order by 3

SEQUENCE# FIRST_CHANGE# TO_CHAR(
--------- ------------- --------
       21    8.6056E+10 13:48:16
       22    8.6056E+10 13:48:22
       23    8.6056E+10 13:48:29

Log sequence 21 was first written to at 1:48 PM so we should recover to a log sequence before this – i.e sequence# 10 (from window dir )


SQL> shutdown immediate;
SQL> startup mount;
RMAN> run {
set until sequence=10;  >>> add one to the sequence number we have to recover until
restore database;
recover database;
}
alter database open resetlogs;

ORA-01190: control file or data file 1 is from before the last RESETLOGS
ORA-01110: data file 1: 'G:\RKANGEL\SYSTEM01.ORA'

RMAN-00571: ===========================================================
RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============
RMAN-00571: ===========================================================
RMAN-03002: failure of alter db command at 09/20/2012 14:15:38
ORA-01147: SYSTEM tablespace file 1 is offline
ORA-01110: data file 1: 'G:\RKANGEL\SYSTEM01.ORA'

SQL> ALTER DATABASE DATAFILE 1 ONLINE;
SQL> RECOVER DATABASE;

ORA-00283: recovery session canceled due to errors
ORA-16433: The database must be opened in read/write mode.


select count(*) from myobjects;


---------------------------------------------------Recover Dropped Table from Recyclebin using Flashback Table-------------------------

Oracle Flashback Table enables you to restore a table to its state as of a previous point in time. It provides a fast, online solution for recovering a table that has been accidentally modified or deleted by a user or application. In many cases, Oracle Flashback Table eliminates the need for you to perform more complicated point-in-time recovery operations.

Oracle Flashback Table:

Restores all data in a specified table to a previous point in time described by a timestamp or SCN.

Performs the restore operation online.

Automatically maintains all of the table attributes, such as indexes, triggers, and constraints that are necessary for an application to function with the flashed-back table.

Maintains any remote state in a distributed environment. For example, all of the table modifications required by replication if a replicated table is flashed back.

Maintains data integrity as specified by constraints. Tables are flashed back provided none of the table constraints are violated. This includes any referential integrity constraints specified between a table included in the FLASHBACK TABLE statement and another table that is not included in the FLASHBACK TABLE statement.

Even after a flashback operation, the data in the original table is not lost. You can later revert to the original state.

FLASHBACK TABLE <table_name> TO BEFORE DROP;

Some other variations of the flashback database command include.

FLASHBACK DATABASE TO TIMESTAMP my_date;
FLASHBACK DATABASE TO BEFORE TIMESTAMP my_date;
FLASHBACK DATABASE TO SCN my_scn;
FLASHBACK DATABASE TO BEFORE SCN my_scn;

--------------------------------------------------Recover deleted Table Data from Recyclebin using Flashback Table---------------------

On Oracle Database 11g (10gR2...), we can rewind one or more tables back to their contents at a previous time without affecting other database objects.

Before we use Flashback Table, We must enable row movement on the table. because rowids will change after the flashback.

Example: Flashback the table back to previous time using SCN


select count(*) from LDBO.test;
COUNT(*)
----------
68781

SQL> SELECT CURRENT_SCN FROM V$DATABASE;

CURRENT_SCN
-----------
1584494

SQL> delete from LDBO.test where rownum <= 50000;

50000 rows deleted.

SQL> commit;

Commit complete.

SQL> select count(*) from LDBO.test;

COUNT(*)
----------
18781

SQL> SELECT CURRENT_SCN FROM V$DATABASE;

CURRENT_SCN
-----------
1587106

Enable row movement:

SQL> alter table LDBO.test enable row movement;

Table altered.

SQL> FLASHBACK TABLE LDBO.test to scn 1584494;

Flashback complete.

SQL> select count(*) from LDBO.test;


QL> alter table LDBO.test disable row movement;

Table altered.


We can rewind the table back to previous time using timestamp:

SQL> alter session set nls_date_format='YYYY/MM/DD HH24:MI:SS';

Session altered.

SQL> select sysdate from dual;

SYSDATE
-------------------
2009/08/30 17:01:09

SQL> delete from LDBO.test ;

68781 rows deleted.

SQL> commit;

Commit complete.

SQL> select sysdate from dual;

SYSDATE
-------------------
2009/08/30 17:03:18

SQL> select count(*) from LDBO.test;

COUNT(*)
----------
0

SQL> alter table LDBO.test enable row movement;

Table altered.

SQL> flashback table LDBO.test to timestamp TO_TIMESTAMP('2009/08/30 17:01:09','YYYY/MM/DD HH24:MI:SS');

Flashback complete.

SQL> select count(*) from LDBO.test;

COUNT(*)
----------
68781

--------------------------------------------------------------------------------------------Flashback Table recover table to different table----------------------

FLASHBACK TABLE test TO BEFORE DROP RENAME TO test2;

flashback table LDBO.test to timestamp TO_TIMESTAMP('2009/08/30 17:01:09','YYYY/MM/DD HH24:MI:SS') RENAME TO test2;




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