Category Archives for Database

OEM DBConsole startup issues on 10g R2 database for 11i/R12

On one of our cloned 11i Instance, I faced issues while trying to start Database Control (aka Enterprise Manager Console) using “emctl start dbconsole“. This post covers issues and resolution (Issues mentioned here are specific to particular Database and Operating System Version) . Instance Details Operating System : Solaris Sparc 64 Bit Database : Oracle […]

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RAC Basics : CRS, Voting Disk, OCR, Cache Fusion ….

Oracle Clusterware (Cluster Ready Services in 10g/ Cluster Manager in 9i) – provides infrastructure that binds multiple nodes that then operate as single server. Clusterware monitors all components like instances and listeners. There are two important components in Oracle clusterware, Voting Disk and OCR (Oracle Cluster Registry). . Voting Disk – is file that resides […]

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Explain Plan In Oracle

One of the most usefull tool which require for both DBAs and Developers to use it effectively to avoid the performance problem of Custom Code specailly in ERP database as well as any database. We should make best use of it.  An execution plan is a list of steps that Oracle will follow in order to execute a SQL […]

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Oracle 9i Multi Master Advance Replication setup, testing and troubleshooting

Objective: This paper is related to the Multi Master Replication setup, testing and troubleshooting. Introduction: In this Multi Master Replication testing two machines are being used. There will be two databases on the two different machines i.e. a) Master1 (Master definition Site) This site will be used for the administration of the Replication setup. b) […]

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Steps / How to Migrate Non ASM Instance Database to ASM Instance

NOTE: Always Do Exercise on Test Environment, First.  Assumptions :  1. ASM Instance is already Created and Ready to Use. 2. DB Instance was Started using ‘spfile’ 3. Disk Group Name : ‘+DGDATA’  – Set the Parameter ‘db_create_file_dest’ to ‘+DGDATA’   alter system set db_create_file_dest=’+DGDATA’ scope=spfile; – Set the Parameter ‘control_file’ to the destination in ASM […]

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Error: ORA-00354 – (Oracle Hidden Parameter : _allow_resetlogs_corruption)

NOTE: This is One of the Hidden Oracle Parameters. DO NOT use it until and unless instructed by Oracle Support. You are trying to start your DATABASE, you found the aforementioned error i.e. ORA-00354. . Required Action: Perform recovery with a good version of the redo log file or perform cancel-based recovery up to, but […]

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AWR (Advance workload Repository)Report in Oracle 10G

AWR is an enhancement/upgradation of statspack, which help us to tune the database. Oracle Database 10g uses a scheduled job, GATHER_STATS_JOB, to collect AWR statistics. This job is created, and enabled automatically when you create a new Oracle database under Oracle Database 10g. GATHER_STATS_JOB, to collect AWR statistics every 1 hour . We can disable […]

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Recover an accidentally deleted file when the database is still open.

On Unix/Linux, when a file is deleted, but a process still has the file open, the file is still there in the filesystem, and only the inode is removed. But the process can continue to use its file handle, and the file can also be accessible under /proc/<pid>/fd . In the following example, we use […]

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RAC Storage

Storage Options for RAC CFS (Cluster File System) – Easy to manage but only available on some platforms.  Does not address striping and mirroring. RAW – Available on all platforms but difficult to manage. Does not address striping and mirroring. NFS – Easy to manage but only available on some platforms.  Does not address striping […]

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Oracle Database Recovery Scenario and Solution

The purpose of this article  is to get acquianted with some of the recovery scenarios , this topic is useful for the folks who is having less experience and looking for good DBA exposure and preparing for interview .    I am trying to  jotting down both RMAN and normal database technique :-  1.Complete Closed […]

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