Oracle Tutorial for beginners

| Last Updated: | In: Oracle

In the late 1960s/early 1970s, specialised data management software appeared – the first database management systems (DBMS). These early DBMS were either hierarchical (tree) or network (CODASYL) databases which were complex and inflexible and could not easily  be modified for new applications or reorganising the data.

In 1974 IBM started a project called System/R to prove the theory of relational databases. This led to the development of a query language called SEQUEL (Structured English Query Language) later renamed to Structured Query Language (SQL) for legal reasons and now the query language of all databases.


In 1978 a prototype System/R implementation was evaluated at a number of IBM customer sites.

By 1979 the project finished with the conclusion that relational databases were a feasible commercial product.

Oracle Database schema

1) SYS (essential core database structures and utilities)
2) SYSTEM (additional core database structures and utilities, and privileged account)
3) OUTLN (utilized to store metadata for stored outlines for stable query-optimizer execution plans.[13])
4) BI, IX, HR, OE, PM, and SH (expanded sample schemas[14] containing more data and structures than the older SCOTT schema).

Simple Query Examples

The following statement selects rows from the employees table with the department number of 30:

The following statement selects the name, job, salary and department number of all employees except purchasing clerks from department number 30:

Tags: , , , , , ,

About: Prem Tiwari

Prem Tiwari is the founder of and is a professional developer who has vast experience in PHP and open source technologies. Apart from this, he is a blogger by hobby.

You may also like:

Follow us!

Get Free Access of 400+ Scripts

Don't worry you'll not be spammed!

Featured eBook

WordPress Security Guide

Free Guide: Learn how to implement security guideline in your WordPress site...


Pincode Finder

pincode-finder tool

Online Pincode Finder

Best tool to locate post Office address and pincodes of all india...