Basics of database

Basic Terms
  • Data
    Data means raw facts.
    Example: Sonu, 25, Delhi
  • Information
    Information is processed data that has meaning.
    Example: Sonu is 25 years old and lives in Delhi.

Table Basics
  • A table is a collection of rows and columns.
  • Tables are used to store data in an organized way.

Database Terminology

In database language:

  • Table is called a Relation
  • Row is called a Tuple
  • Column is called an Attribute

Database

A database is a collection of one or more tables.

A database can contain:

  • Tables
  • Views
  • Triggers
  • Other database objects

RDBMS

RDBMS (Relational Database Management System) is a type of software used to create and manage databases.

Key points about RDBMS:

  • It stores data in the form of tables
  • Tables can be related to each other
  • It helps to store, retrieve, update, and delete data easily

Popular RDBMS Software

Some commonly used RDBMS are:

  • Oracle
  • Microsoft SQL Server
  • DB2
  • MySQL
  • PostgreSQL

... means the list is very long and cannot be shown completely.


SQL

All the RDBMS listed above use SQL.

  • SQL stands for Structured Query Language
  • SQL is used to create and manage databases
  • SQL is a standard language
  • SQL is easy to learn because it is close to English
  • SQL is a 4th generation language