Oracle Training in Chennai

SAKTHI SOFTWARE SOLUTIONS

Final Year Projects - 2014

RVR Towers, 1st Street, 3rd Main Road, Annanagar, Behind Nalli Silks, 

Chennai 600 040,Tel: 044-43016888 / 9710780469 Email: fresherfocus@gmail.com, sssprojects2013@gmail.com 

URL: www.sssedu.in

Oracle Database Architecture

Architecture

Oracle Server

Oracle Server is a Database Management System that provides an Open, Comprehensive, Integrated approach to information management. This Oracle Server consists of an Oracle Instance and an Oracle database.

Oracle Instance

Through the Oracle Instance we can access the database. One Instance can open and use only one database. It is non-persistent area allocated in Ram. This Instance is consists of Memory area and Background Process.

Oracle Database

Oracle Database is consists of one or more data file, one or more control file, two or more log file.

User process

The user starts a tool such as SQL*Plus or runs an application developed using a tool such as Forms. This application or tool is executed as a user process.

Server process

In the most basic configuration, when a user logs on to the Oracle server, a process is created on the computer running the Oracle server. This process is called a server process.

System Global Area

SGA allocated at the instance startup. It contains some components they are playing important role in the Architecture

Shared pool

The Shared pool consists of library cache and dictionary cache.

Library cache

Library cache divided as shared SQL area, shared PL/SQL area. It maintains the Least Recently used algorithm. Syntactic checking verifies that keywords, object names, operators, delimiters are placed correctly in oracle code. Semantic checking verifies that references to database objects and host variables are valid. In library cache generated a hash value for each statement when it’s parsed.

There are two type of parsing. When the statement executed first time the hard parse generate the hash value, if the query executed repeatedly they can use the exist hash value it’s known as soft parse.