Redolog Buffer Cache : SGA Component of Oracle

The redo log buffer is a circular buffer in the SGA that stores redo entries describing changes made to the database.A redo record is a data structure that contains the information necessary to reconstruct, or redo, changes made to the database by DML or DDL operations. Database recovery applies redo entries to data files to reconstruct lost changes.The database … Read more

Shared /Large/Java/Result Pool: SGA Component of Oracle

The shared pool caches various types of program data.For example, the shared pool stores parsed SQL, PL/SQL code, system parameters, and data dictionary information. The shared pool is involved in almost every operation that occurs in the database. For example, if a user executes a SQL statement, then Oracle Database accesses the shared pool. This section includes the following … Read more

SPLUNK’s Advance Topic

Macros Search macros are reusable chunks of Search Processing Language (SPL) that you can insert into other searches. Search macros can be any part of a search, such as an eval statement or search term, and do not need to be a complete command. You can also specify whether the macro field takes any arguments. • … Read more

Crontab : RMAN Backup

Automate RMAN Backup using Shell Script In a real environment, you will not manually trigger all the Oracle database backups. You need an automated mechanism to trigger RMAN backups. Create directory On your database server, create a directory to hold RMAN backups and all related files. All the RMAN backups, logs and backup scripts are … Read more

Roles and Licensing in Splunk

Roles: There are basically three different types of Roles in Splunk:User: This is the basic role in Splunk which provides access to all shared data sets to be read, viewed and monitored. Here you can create dashboard but cannot publish it for other users.Power User: This is an advanced role in Splunk which grants you … Read more

How to Change SQL*Plus Prompt to Reflect Username & Instance Name ??

1. Verify that client networking connections are functional. Clients must be able to login to sql*plus with username/password/host string (where host string is the alias created for the specific sid). i.e.: username: <dbuser> password: <dbpassword> host string: <connectstring> -or- username: <dbuser>/<password>/<connectstring> 2. Login as oracle user and add scripts at the end of the glogin.sql … Read more

Background Processes in Oracle ASM

Once the ASM instance is started, all the basic background processes, as well as some that are specific to the operation of ASM, are started. On Linux, the ASM processes can be listed using the following command: Some of the more important ASM background processes: ARBx These are the slave processes that do the rebalance … Read more

Row Chaining and Row Migration

Row Chaining Occurs when the row is too large to fit into one data block when it is first inserted. In this case, Oracle stores the data for the row in a chain of data blocks (one or more) reserved for that segment. Row chaining most often occurs with large rows, such as rows that … Read more

Overview of the Program Global Area (PGA)

The PGA is memory specific to an operating process or thread that is not shared by other processes or threads on the system. Because the PGA is process-specific, it is never allocated in the SGA. The PGA is a memory heap that contains session-dependent variables required by a dedicated or shared server process. The server … Read more