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There will be only one database

Archive for March, 2011

The first and the only Oracle user group application in the world. From TROUG

Posted by fsengonul on March 27, 2011

http://itunes.apple.com/tr/app/turkish-oracle-user-group/id424769558?mt=8
Dünyanın ilk ve tek oracle kullanıcı grubu uygulamasını bu linkten indirebilirsiniz. Tabi ki TROUG’den. Bu uygulama ile etkinliklerimizi takip edebilir ve forumlarımıza katılabilirsiniz. Eline sağlık Zekeriya Beşiroğlu.

You may download the first and the only oracle user group application in iTunes from this link. Of course it’s from TROUG.
You can follow our events and write on our forums with this unique application. Thank you Zekeriya Beşiroğlu.

Posted in TROUG | Leave a Comment »

TROUG@Sakarya Üniversitesi

Posted by fsengonul on March 25, 2011


Bugün , Türkiye Oracle Kullanıcıları Grubu (TROUG) olarak Sakarya Üniversitesi’ndeki “Bilişim ve Teknoloji Şöleni” nindeydik. Gökhan Atıl ve Gürcan Orhan’la birlikle Sapanca Gölü manzaralı bu güzel kampüste , mükemmel bir organizasyona katılıp , oracle ve iş hayatı hakkındaki tecrübelerimizi öğrencilere aktarmaya çalıştık. Onların sorularından biz de çok şey öğrendik.
Türkiye’de meraklı, azimli ve araştırmaktan yılmayan bir nesil yetişiyor. Artık, teknolojiyi takip etmekten , teknoloje yön vermeye doğru gidiyoruz. Çok yakında , eminim ki, veritabanı konusunda da teknoloji üreten bir ülke haline geleceğiz.
Bizi davet eden ve en iyi şekilde ağırlayan Burak Çakmak’a ve Bilgisayar Topluluğu’nun diğer üyelerine çok teşekkürler.

Today (24 March 2011) as members of Turkish Oracle User Group (TROUG), Gökhan Atıl, Gürcan Orhan and I were in Sakarya to join Sakarya University Computer Science Community’s Technology and Informatics Festival to share our experiences with the University Students. While having a beautiful lake view of the University Campus, we attended this well organized event and shared our experiences & knowledge about Oracle and business life in general. We also learnt a lot from the questions they’ve asked.
It was so nice to see the young students with curiousity, tender and dedicated to research. We are turning into setting the way to the technology instead of solely following it. Soon, I’m quite sure that, Turkey will become a database technology provider.
I’d like to thank so much to Mr. Burak Cakmak and other members of Computer Science Community for their kindness and taking good care of us.

Posted in TROUG | 3 Comments »

Playing with policy managed databases

Posted by fsengonul on March 17, 2011

It was a great idea to try quality of service in 11gR2. But unfortunately at the moment it only supports OLTP workload.(average response time of less than one second, and preferably, an average response time of less than 0.5 seconds) and it does not support parallel queries.

Even though I can’t use them at the moment, I can still gain something from the server pool architecture.
I can move nodes from one database to another.
Below you may find my first tries.


oracle@node01:/home/oracle>srvctl status srvpool -g POOL1B

Server pool name: POOL1B
Active servers count: 1
oracle@node01:/home/oracle>srvctl status srvpool -g POOL1B -a
Server pool name: POOL1B
Active servers count: 1
Active server names: node14
NAME=node14 STATE=ONLINE
oracle@node01:/home/oracle>srvctl config database -d XDB
Database unique name: XDB
Database name: XDB
Oracle home: /u01/app/oracle/product/11.2.0/dbhome_1
Oracle user: oracle
Spfile: +DATA/XDB/spfileXDB.ora
Domain:
Start options: open
Stop options: immediate
Database role: PRIMARY
Management policy: AUTOMATIC
Server pools: POOL1B
Database instances:
Disk Groups: DATA
Mount point paths:
Services:
Type: RAC
Database is policy managed
oracle@node01:/home/oracle>srvctl status srvpool -g POOL1B -a
Server pool name: POOL1B
Active servers count: 1
Active server names: node14
NAME=node14 STATE=ONLINE
oracle@node01:/home/oracle>srvctl start database -d XDB
oracle@node01:/home/oracle>srvctl status database -d XDB
Instance XDB_1 is running on node node14
oracle@node01:/home/oracle>srvctl modify srvpool -g POOL1B -n "node14,node15"
oracle@node01:/home/oracle>srvctl status srvpool -g POOL1B -a
Server pool name: POOL1B
Active servers count: 2
Active server names: node14,node15
NAME=node14 STATE=ONLINE
NAME=node15 STATE=ONLINE
oracle@node01:/home/oracle>srvctl status database -d XDB
Instance XDB_1 is running on node node14
Instance XDB_4 is running on node node15
oracle@node01:/home/oracle>srvctl modify srvpool -g POOL1B -n "node14"
PRCS-1011 : Failed to modify server pool POOL1B
CRS-2736: The operation requires stopping resource 'ora.XDB.db' on server 'node15'
CRS-2738: Unable to modify server pool 'ora.POOL1B' as this will affect running resources, but the force option was not specified
oracle@node01:/home/oracle>srvctl stop instance -d XDB -n node15
oracle@node01:/home/oracle>srvctl status database -d XDB
Instance XDB_1 is running on node node14
Instance XDB_4 is not running on node node15
oracle@node01:/home/oracle>srvctl modify srvpool -g POOL1B -n "node14"
oracle@node01:/home/oracle>srvctl status database -d XDB
Instance XDB_1 is running on node node14
oracle@node01:/home/oracle>

Posted in Exadata, oracle | Leave a Comment »

What happens when exadata has lost two disks?

Posted by fsengonul on March 8, 2011

Actually the question is “What happens when ASM has lost two disks in different failgroups when redundancy is normal?”
We’re sure that there will be no problem if we lose all of the disks in a single failgroup but in order to answer the question we have to understand how mirroring works in ASM.
In normal redundancy, mirror of each extent is written to another disk in another failgroup. This causes a partnership between these disks. As far as I’ve found out this information is kept in the x$kfdpartner table.

From the following query it seems that an extend in DATA_CD_10_CEL27 has a mirror on DATA_CD_07_CEL01. If we lose these two disks then the system has to crash.
On the other hand if we lose DATA_CD_10_CEL27 and the disks in the partner list ( 8 disks at the moment) stays alive, there will be no problem if we lose another disk.


select dg.name dg_name,
d.name disk_name,
pd.name partner_name
from x$kfdpartner p,v$asm_diskgroup dg,v$asm_disk d,v$asm_disk pd
where
p.grp=dg.group_number
and d.disk_number=p.disk and d.group_number=p.grp
and pd.disk_number=p.number_kfdpartner and pd.group_number=p.grp
and dg.name='DATA' and d.name='DATA_CD_10_CEL27';

DG_NAME DISK_NAME PARTNER_NAME
DATA DATA_CD_10_CEL27 DATA_CD_07_CEL01
DATA DATA_CD_10_CEL27 DATA_CD_06_CEL01
DATA DATA_CD_10_CEL27 DATA_CD_07_CEL25
DATA DATA_CD_10_CEL27 DATA_CD_06_CEL25
DATA DATA_CD_10_CEL27 DATA_CD_07_CEL26
DATA DATA_CD_10_CEL27 DATA_CD_06_CEL26
DATA DATA_CD_10_CEL27 DATA_CD_07_CEL28
DATA DATA_CD_10_CEL27 DATA_CD_06_CEL28

Posted in Exadata, oracle | Leave a Comment »