Interview Questions.

Q1. How Should I Set The Database To Improve Flashback Performance?

Oracle’s suggestions are:

Use a fast report gadget in your flash recuperation place, ideally without running device file caching. It is usually recommended to use a record machine that avoids working device report caching, which includes ASM.

Configure sufficient disk spindles for the report gadget so as to keep the flash restoration region. For massive manufacturing databases, multiple disk spindles can be needed to guide the required disk throughput for the database to jot down the flashback logs correctly.

If the garage system used to preserve the flash restoration area does now not have non-unstable RAM, attempt to configure the report system on top of striped garage volumes, with a relatively small stripe size which include 128K. This will permit every write to the flashback logs to be unfold throughout more than one spindles, improving overall performance

For huge, production databases, set the init.Ora parameter LOG_BUFFER to be at the least 8MB. This makes certain the database allocates most memory (typically 16MB) for writing flashback database logs.

Q2. Upgrading To 12.2.2? Do You Want Extra Speed? Use A Logon Trigger For Parallelism?

When upgrading your Demantra software from an older version without delay to twelve.2.2, you can limit the upgrade time.  You can pressure parallelism the usage of a Logon trigger at the server.

Creation of new Indexes on sales information can take long term.

As part of the upgrade there is a script constructing a new set of indexes, one per engine profile, on every profile quantity_form expression.

The introduction of the index can take a long time on huge statistics tables.

Remember to disable or drop that cause while the improve has completed.

The following trigger became created as SYS database consumer and examined correctly through creating DEMANTRA database consumer and logging in with it:

CREATE OR REPLACE TRIGGER force_parallel_ddl_trg

AFTER LOGON ON database

BEGIN

 IF (USER=’DEMANTRA’) THEN

 EXECUTE IMMEDIATE ‘ALTER SESSION FORCE PARALLEL DDL’;

 END IF;

END force_parallel_ddl_trg;

/

Make certain to:

Modify DEMANTRA to be the database schema call.

Drop it after it is not needed anymore the use of the subsequent:

DROP TRIGGER force_parallel_ddl_trg;

Q3. Can Rman Be Used To Backup Flashback Logs?

No. Flashback Logs are not sponsored up. Even if the command BACKUP RECOVERY AREA is used to backup the contents of the FRA to tape only the following document sorts are backed up: complete and incremental backup sets, control document autobackups, datafile copies, and archived redo logs.

Flashback Logs are considered to be trient documents and can't be backed up by using RMAN. They aren't needed for media recuperation.

Q4. Errors With The Demantra Batch Or Simulation Engine?

The key engine logs are found underneath the root force of the device where the engine is launched. The folder that holds those logs generally have Engine2k somewhere within the call.

Note that there must be as a minimum Engine2k logs (those are the logs that display the real splitting and forecasts that the engine does) on this folder.

However, to write the grasp EngineManager logs to this folder you need to visit the Engine Administrator (..Demand PlannerAnalytical Enginesbin –> Settings –> Configure) and exchange the Engine Manager Log tab from STD to FILE.

It is NOT cautioned to re-register the engine after making this modification.

Q5. Can You See The Progress Of A Flashback Database Operation?

Yes, you could. During a FLASHBACK DATABASE operation you can query V$SESSION_LONGOPS from any other session to peer the development of the flashback.

The FLASHBACK DATABASE operation has  wonderful levels: the real flashback and the media recovery that takes place afterwards to bring the database to a regular country.

While the actual flashback is running you’ll see the following message in V$SESSION_LONGOPS, on Oracle 11gR2:

Flashback Database: Flashback Data Applied : 238 out of 282 Megabytes performed

During the media healing, the subsequent messages can be seen:

Media Recovery: Redo Applied : 263 out of zero Megabytes finished

Media Recovery: Average Apply Rate : 1164 out of zero KB/sec carried out

Media Recovery: Last Applied Redo : 626540 out of 0 SCN+Time accomplished

Media Recovery: Elapsed Time : 232 out of zero Seconds performed

Media Recovery: Active Time : 116 out of zero Seconds achieved

Media Recovery: Active Apply Rate : 1859 out of 0 KB/sec finished

Media Recovery: Maximum Apply Rate : 1859 out of 0 KB/sec completed

Media Recovery: Log Files : 15 out of zero Files completed

Media Recovery: Apply Time in keeping with Log : 7 out of 0 Seconds finished

Q6. How To List Restore Points In Rman?

In RMAN you can use the LIST RESTORE POINT [ALLyou use a recuperation catalog you can use the view RC_RESTORE_POINT in the restoration catalog repository, or the command the V$RESTORE_POINT within the goal database.

Q7. Installation Of The Demantra Base Application Or Patches?

Create a C:/Tmp folder at the system where the setup.Exe will be accomplished previous to the installation as this may generate a log record to this folder

Note that there may also be a few ancillary logs under the following folders:

Demand PlannerDatabase ObjectsOracle Server (Oracle again quit database)

Demand PlannerDatabase ObjectsMicrosoft SQL Server (Sql Server returned end database)

Q8. Stored Procedure Errors With Active_proc_dyn Somewhere In The Error Message?

To view the errors go to Business Modeler –> Tools –> Procedure Error Log

Note that this looks to the backend table known as db_exception_log

Q9. When Are The Flashback Logs Deleted?

Flashback logs are controlled by using Oracle only. Oracle will attempt to preserve as a good deal Flashback logs as had to fulfill the DB_FLASHBACK_RETENTION_TARGET parameter. However, if there’s area pressure inside the Flash Recovery Area (FRA), flashback logs can be deleted to make room for different things, like backups and archived logs, for example.

If the fast healing vicinity has enough space, then a flashback log is created each time necessary to fulfill the flashback retention target.

If a flashback log is antique sufficient that it is now not needed to fulfill the flashback retention goal, then a flashback log is reused.

If the database have to create a brand new flashback log and the quick healing place is complete or there is no disk area, then the oldest flashback log is reused as an alternative.

If the quick healing location is complete, then an archived redo log that is reclaimable in keeping with the FRA policies may be mechanically deleted with the aid of the short recuperation area to make space for other files. In this case, any flashback logs that could require the usage of that redo log record for the use of FLASHBACK DATABASE also are deleted.

No report in the speedy recuperation area is eligible for deletion if it's miles required to fulfill a assured repair factor. Thus, retention of flashback logs and different documents required to satisfy the guaranteed restore point, similarly to files required to satisfy the backup retention policy, can cause the fast recovery area to fill completely.

Q10. Issues With Ebs Integration To Demantra?

In fashionable, maximum EBS facet activities (ex. Planning Data Pull) may be logged the use of Note 245974.1 but, the Shipment and Bookings Collection process will have greater logging turned on by means of converting MSD_DEM: Debug Mode to Yes (default is No).

Note that as the Shipment and Bookings Collection process moves to the alternative facet of the wall from EBS facet of the database to the Demantra aspect of the database (commonly indicated by while you start seeing references to the Demantra schema or tables like t_src_items_tmpl or t_src_sales_tmpl_err) then the mistakes can also need to be tracked using the Workflow or Active_Proc_Dyn troubleshooting sections of this be aware.

Q11. Is It Possible To Specify The Size Of The Flashback Buffer In The Sga?

Yes, however not directly. The length of the Flashback Buffer is about to two * LOG_BUFFER.

For performance motives, it’s advocated to set LOG_BUFFER to at least 8MB for

databases going for walks in Flashback Mode.

UPDATE: For massive 11.1.Zero.7+ databases with greater than a 4GB SGA, you can keep in mind setting LOG_BUFFER to values inside the variety of 32-sixty four MB.

Q12. Error Starting The Webserver And/or Deploying The Demantra War File?

Review the Collaborator.Log that is observed beneath the …Collaboratordemantralogs folder on the web server in which Demantra is walking.

Also, every person webserver (ex. OAS, JRUN, Tomcat, Websphere, and so forth…) will have their personal character logs in various directories which also can be consulted.

The character webserver documentation must be reviewed for those log locations.

Q13. What Happens If Rvwr Cannot Write To Disk?

It relies upon at the context in which the write mistakes takes place:

If there’s a Guaranteed Restore Point, the database crashes to make certain the restore point assure isn't always voided.

If there isn’t a Guaranteed Restore Point and it’s a number one database, the Flashback Mode could be robotically grew to become off for the database, on the way to continued to function normally.

If there isn’t a Guaranteed Restore Point and it’s a standby database, the database will grasp till the purpose of the write failure is constant.

Q14. Oracle Demantra Customer, Are You Considering An Upgrade To You Oracle Demantra Software?

There are 3 critical MOS notes that you can want to check:

12.2.1, 12.2.2, 12.2.3 and 12.2.Four Install Upgrade ADVISOR: Demantra (Doc ID 1664177.2)

DEMANTRA WARNING Have you OR are you Planning to Upgrade to Release 12.2.2? Upgrade from 12.2.2 to 12.2.3 or 12.2.Four Collections EP Load is Failing ORA-20002, ORA-00001, ORA-06512 (Doc ID 1917715.1)

Upgrading to Demantra 12.2.Four? Here are contemporary recognized problems from Demantra Development, Proactive Services and Oracle Support (Doc ID 1928367.1)