Define Oracle Instance Size |
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- čas přidán 21. 07. 2024
- In this episode of daily DBA, I pick up 5 important #DBA related questions and give my answers! Do not forget to checkout BONUS QUESTION at the end of the video!
00:00 All excited to start the episode
0:54 What are the differences between flashback database and guaranteed restore point?
7:32 Why do we need to set semaphore setting? How semaphore parameter value is calculated? on what basis it's calculated whether it's based on RAM or what? If it's based on RAM then at each time of RAM upgrade will the semaphore settings will be changed?
-- docs.oracle.com/en/database/o...
11:51 You have fresh server with 64GB of RAM and you are asked to install 4 db’s in that server how will u allocate the ram for each DB. How is this calculation done?
15:07 If your not using active dataguard configuration if Block corrupted on standby how will recover corrupted block on standby
18:40 While recovering corrupted block manually i.e BLOCKRECOVER DATAFILE 2 BLOCK 13; could you please help on what happens internally, like from where oracle gets the original block?
20:07 # dba challenge!
Bonus Question
22:45 How is your typical day at work?
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Thanks a ton for such detailing 🙏 The way you explain gets sync with mind so quickly and easily.
In oracle 12c I think there are parameters db_ultra_safe db_checksum to protect blocks from corruption on standby database.
Block Changed value will be applied or recovered from archive logs.
I think block with value of 1000 , will be restored from backup but will also be recovered by either increment backup or available archive logs.
Correct!
Hi Arun DBA challenge Q : It checks the control file scn mismatch with previous Rman backup and looks for scn is available in flashback or archive and applies it, if not throws an error to make database to reset logs..
Can you make video on oracle installation prerequisites for Linux and windows.
I think you can note down the scn till value 2000 in the block and restore the rman backup and recover till this scn.. I hope this should help
Sir your explanation is good
Please try to talk about AutoUpgrade tool.
Thanks
Maybe in upcoming episodes !
I enjoyed the bonus question 👌
Glad you liked it!
Nice explain sir
Use flashback logs and in a dataguard setting use the service name.of the primary to recover those missing blocks. Pls how did I do?
Awesome
Nice
What are the things to check when import of the schema or table get failed? #dailyDBA
;) check the import error messages :P
Hi Arun
As you said if not using active data guard coruption block will recover by fal_server on standby
Here with that fal_server parameter will keep on both sides right like primary and standby .if block corputed on primary fal_seever will recover for us with help standby block right ...
.so why we go for manual recover the block ??????
If using fal_server parameter no need to go for manual recover the coruption bllock even if corputed on primary as well as standby
Coz apart from block recovery, the parameter has other work to do also in DG environment. Read about it.
@@dbagenesis it will help ful gap resolution right
Can you please help me understand the use of swap? The point that confuses me is that, if we have already configured the database memory parameters such as max SGA or pga size, how can the database look for more memory than which is already allocated to the database? Please correct me if my understanding is incorrect
Alright, will answer what is SWAP in upcoming episodes.
Meanwhile, what do you mean by "How can the database look for more memory that what is already allocated to the database"
What I mean is , if my server has 10gb of ram- and If I have allocated 7gb of ram to the database ( sga, pga components) , will my database still need swap memory since I have sufficient ram?
We have archive archive log so it's will recover from there #dba challenge
You are right!
Hi Arun, In one of near videos you mentioned regarding putty artical/course in support.dbagenesis.com..can you please mention again how to search it in the website.
Putty course is now merged with Linux course. You can enroll into the Linux course for free dbagenesis.com/p/linux-administration-for-beginners
Hi buddy fal sever and fal client should be set up on both sides of primary and standby ?
Yes, correct
@@dbagenesis awesome
How to calculate we need this much of SGA?
Just start with any number and increase it as per your needs
Perfect explanation 👌. .. but have one query on first question.. suppose we have set flashback retention to 24hours and we have set some guarantee point...it mean that it's ignoring the value of flashback retention during guarantee point??
It depends upon type of recovery, if you go for flashback / guaranteed restore point. Depends upon the recovery you choose it will work..
Yes, you will have flashback logs till the guaranteed restore point. This might make your FRA location quickly full.
Just apply archive to recover if no backup #DBAchallenge