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Lesson 2 Prerequisites
ObjectiveVerify that you have the right background for this course.

Tuning Environment Prerequisites

In order to get the most from this course you should have a basic understanding of the UNIX operating system, PL/SQL coding techniques, and the following Oracle database concepts:
  1. Oracle SGA and PGA concepts
  2. Oracle networking concepts
  3. Oracle environmental configuration
If you do not feel comfortable with one or more of these topics, techniques, or procedures, you may want to consider taking the course
  1. Database Architecture.

Components of Oracle SGA

The Oracle System Global Area (SGA) is a memory structure that contains data and control information for an Oracle Database instance. It consists of the following components:
  1. Database buffer cache: This is where the data blocks that have been read from the datafiles are stored. The buffer cache is used to reduce the number of disk reads required to access data, improving performance.
  2. Shared pool: This area of the SGA stores shared SQL and PL/SQL code, as well as control information for the database.
  3. Redo log buffer: This is a buffer that stores redo entries (information used to reconstruct changes made to the database in the event of a failure).
  4. Large pool: This is an optional area of the SGA that can be used to store large memory allocations, such as the shared server process work areas and the recovery writer (RWR) process work area.
  5. Java pool: This is an optional area of the SGA that is used to store Java-related data, such as Java code and data.
  6. Streams pool: This is an optional area of the SGA that is used by the Oracle Streams feature to store data related to the capture, propagation, and apply processes.
  7. Fixed SGA: This is a fixed-size area of the SGA that stores metadata and control information for the database. It includes the System Change Number (SCN) header, the database lock and latch structures, and the process and session information.

The first three courses in the SQL Tuning series,
  1. 1) Oracle Performance Tuning ,
  2. 2) Tuning the Oracle Instance, and
  3. 3) Tuning Oracle SQL.
The next lesson describes what you need to take this course.