Shkenca Kompjuterike-Computer Science

ACTIVE_INSTANCE_COUNT Enables you to designate one instance in a two-instance cluster as the primary instance and the other instance as the secondary instance. This parameter has no functionality in a cluster with more than two instances. When you set this parameter to 1, the first instance you start up becomes the primary instance and accepts client connections. The second instance starts up as a secondary instance and can accept client connections only if the first instance fails. In such an event, the secondary instance becomes the primary instance. When the failed instance can once again be started up, it starts up as the secondary instance, and will not accept client connections unless the current primary instance fails. https://docs.oracle.com/database/121/REFRN/GUID-74B33671-D6EA-469D-95E8-80AA56CC3F6F.htm#REFRN10001

Disponueshmëria i referohet mbrojtjes së informacionit dhe sistemeve të informacionit nga ndërprerjet të paautorizuara.  Sigurimi i  disponueshmërisë është sigurimi i qasjes në kohë dhe besueshmeria e përdorimit të informacionit dhe sistemeve të informacionit. Disponueshmëria është një nga shtyllat më të rëndësishme të sigurisë së të dhënave. Siguron që të dhënat në bazën e të dhënave janë gjithnjë të arritshme sa herë që nevojiten nga organizata. Nuk ka asnjë kuptim të mbajm të dhënat konfidenciale dhe të sigurta kur të dhënat nuk janë të disponueshme për qasje. Disponueshmëria e të dhënave sigurohet përmes teknikave të bekapit dhe të rikuperimit dhe mekanizmat e kontrollit të konkurrencës . Së bashku me fatkeqësitë natyrore, po ashtu edhe  gabimet e njeriut ndikojnë në disponueshmërinë e të dhënave. 

Partitioning Overview Partitioning allows a table, index, or index-organized table to be subdivided into smaller pieces, where each piece of such a database object is called a partition. Each partition has its own name, and may optionally have its own storage characteristics. Benefits of Partitioning Partitioning can provide tremendous benefit to a wide variety of applications by improving performance, manageability, and availability. It is not unusual for partitioning to greatly improve the performance of certain queries or maintenance operations. Moreover, partitioning can greatly simplify common administration tasks. Partitioning also enables database designers and administrators to solve some difficult problems posed by cutting-edge applications. Partitioning is a key tool for building multi-terabyte systems or systems with extremely high availability requirements. This section contains the following topics: Partitioning for Performance Partitioning for Manage...

This section describes best practices for determining backup frequency, using the RMAN recovery catalog, and for using Oracle database backup options such as Block Change Tracking. Determine a Backup Frequency  and Retention Policy It is important to determine a backup frequency policy and to perform regular backups. A backup retention policy helps ensure that needed data is not destroyed. Factors Determining Backup Frequency  Frequent backups are essential for any recovery scheme. You should base the frequency and content of backups on the following criteria: Criticality of the data:  The  Recovery Point Objective (RPO) determines how much data your business can acceptably lose if a failure occurs. The more critical the data, the lower the RPO and the more frequently data should be backed up. If you are going to back up certain tablespaces more often than others, with the goal of getting better RPO for those tablespaces, then you also must plan for doing TS...