MySQL Introduction

By Prof. B.A.Khivsara

Note: The material to prepare this presentation has been taken from internet and are generated only for students reference and not for commercial use.

Introduction to MySQL

MySQL is the most popular Open Source Relational SQL Database Management System. MySQL is one of the best RDBMS being used for developing various web-based software applications. MySQL is developed, marketed and supported by MySQL AB, which is a Swedish company.

What is a Database? A database is a separate application that stores a collection of data. Each database has one or more distinct APIs for creating, accessing, managing, searching and replicating the data it holds.

A Relational DataBase Management System (RDBMS) is a software that − Enables you to implement a database with tables, columns and indexes.

Guarantees the Referential Integrity between rows of various tables.

Updates the indexes automatically.

Interprets an SQL query and combines information from various tables.

RDBMS Terminology Database − A database is a collection of tables, with related data.

Table − A table is a matrix with data. A table in a database looks like a simple spreadsheet.

Column − One column (data element) contains data of one and the same kind, for example the column postcode.

Row − A row (= tuple, entry or record) is a group of related data, for example the data of one subscription.

Redundancy − Storing data twice, redundantly to make the system faster.

RDBMS Terminology

Primary Key − A primary key is unique. A key value can not occur twice in one table. With a key, you can only find one row.

Foreign Key − A foreign key is the linking pin between two tables.

Compound Key − A compound key (composite key) is a key that consists of multiple columns, because one column is not sufficiently unique.

Index − An index in a database resembles an index at the back of a book.

Referential Integrity − Referential Integrity makes sure that a foreign key value always points to an existing row.

RDBMS Database example

• Oracle

• MySQL

• Ms-Access

• PostgreSQL

• Microsoft SQL Server

• IBM DB2

• SQLite

• Etc……….

MySQL Database • MySQL is an open-source database

• MySQL is customizable because it is an open source database

• MySQL is quicker than other databases so it can work well even with the large data set.

• MySQL supports many languages like PHP, PERL, C, C++, JAVA, etc.

• MySQL uses a standard form of the well-known SQL data language.

• MySQL supports large databases, up to 50 million rows or more in a table. The default file size limit for a table is 4GB, but you can increase this (if your operating system can handle it) to a theoretical limit of 8 million terabytes (TB).

MySQL Data Types Categaries Data Types Numeric Data Type

INT, FLOAT(m,d), DOUBLE(m,d), DECIMAL(m,d)

Date and Time Data Type:

DATE, DATETIME,TIME, TIMESTAMP,YEAR

String Data Types:

CHAR,VARCHAR,TEXT, LONGTEXT,BINARY

Large Object Data Types (LOB) Data Types:

TINYBLOB, BLOB, MEDIUMBLOB, LONGTEXT

Command to Install MySQL in ubuntu • sudo apt-get install mysql mysql-client mysql-server

How to start MySQL • First install mysql then write following command on command

prompt

•mysql -u root –p • Then Enter Password, it will show you MySQL prompt

Database related commands-CREATE

• Syntax to create database

• CREATE DATABASE database_name;

• Example:

• Let's take an example to create a database name "employees"

• CREATE DATABASE employees;

Database related commands-SHOW & USE

• You can check the created database by the following query:

• SHOW DATABASES;

• You can use SQL command USE to select a particular database.

• Syntax:

• USE database_name;

• Example:

• Let's take an example to use a database name "customers".

• USE customers;

Database related commands-DROP

• You can drop/delete/remove a MySQL database easily with the MySQL command. You should be careful while deleting any database because you will lose your all the data available in your database.

• Syntax:

• DROP DATABASE database_name;

• Example:

• Let's take an example to drop a database name "employees"

• DROP DATABASE employees;

How to Connect remote MySQL server • To connect remote MySQL server, use the -h (host) with IP

Address of remote machine.

• # mysqladmin -h 172.16.25.126 -u root -p

Schema Objects in Oracle and MySQL

Oracle MySQL AFTER trigger trigger

BEFORE trigger trigger

Check constraint Check constraint

Column default Column default

Database Database

Foreign key Foreign key

Index Index

Package N/A

PL/SQL function Routine

PL/SQL procedure Routine

Primary key Primary key

Role N/A

Schema Objects in Oracle and MySQL

Oracle MySQL Schema Schema

Sequence AUTO_INCREMENT for a column

Snapshot N/A

Synonym N/A

Table Table

Tablespace N/A

Temporary table Temporary table

Trigger for each row Trigger for each row

Unique key Unique key

User User

View View

REFERENCES

• http://www.mysqltutorial.org/

• https://www.javatpoint.com/mysql-tutorial

• https://www.tutorialspoint.com/mysql/