vighnesh1521 / mysql

MySQL

MySQL is a widely used relational database management system (RDBMS). MySQL is free and open-source. MySQL is ideal for both small and large applications.

What is MySQL?

• MySQL is a relational database management system
• MySQL is open-source
• MySQL is free
• MySQL is ideal for both small and large applications
• MySQL is very fast, reliable, scalable, and easy to use
• MySQL is cross-platform
• MySQL is compliant with the ANSI SQL standard
• MySQL was first released in 1995
• MySQL is developed, distributed, and supported by Oracle Corporation.

Who Uses MySQL?

• Huge websites like Facebook, Twitter, Airbnb, Booking.com, Uber, GitHub, YouTube, etc.
• Content Management Systems like WordPress, Drupal, Joomla!, Contao, etc.
• A very large number of web developers around the world

What is RDBMS?

• RDBMS stands for Relational Database Management System.
• RDBMS is a program used to maintain a relational database. -RDBMS is the basis for all modern database systems such as MySQL, Microsoft SQL Server, Oracle, and Microsoft Access. -RDBMS uses SQL queries to access the data in the database.

What is a Database Table?

• A table is a collection of related data entries, and it consists of columns and rows.
• A column holds specific information about every record in the table.
• A record (or row) is each individual entry that exists in a table.

What is a Relational Database?

A relational database defines database relationships in the form of tables. The tables are related to each other - based on data common to each.

Some of The Most Important SQL Commands

• SELECT - extracts data from a database
• UPDATE - updates data in a database
• DELETE - deletes data from a database
• INSERT INTO - inserts new data into a database
• CREATE DATABASE - creates a new database
• ALTER DATABASE - modifies a database
• CREATE TABLE - creates a new table
• ALTER TABLE - modifies a table
• DROP TABLE - deletes a table
• CREATE INDEX - creates an index (search key)
• DROP INDEX - deletes an index

Start Using MySQL

use mysql;

Create database

CREATE DATABASE testDB;

Create Table

  CREATE TABLE Persons (
->     PersonID int,
->     LastName varchar(255),
->     FirstName varchar(255),
->     Address varchar(255),
->     City varchar(255)
-> );

Viewing Table Details

    describe Persons;

Inserting Values to the table created

  insert into Persons(PersonID, LastName, FirstName, Address, City)
-> VALUES(124, 'K U', 'SUDEEP', 'PEENYA', 'BANGALORE'),
-> (125, 'C', 'YASHAS', 'MALLESHWARAM', 'BANGALORE'),
-> (126, 'K R', 'SUMAN', 'YELAHANKA', 'BANGALORE'),
-> (127, 'K', 'KISHORE', 'KURUBARAHALLI', 'BANGALORE'),
-> (128, 'B N', 'SAGAR', 'KURUBARAHALLI', 'BANGALORE');

Viewing the table

 select * from Persons;

Drop the table

  DROP TABLE Persons;

MySQL SHOW WARNINGS statement

When you execute a statement, if errors, warnings, or notes occur, you can use the SHOW WARNINGS diagnostic statement to display detailed information.

  SHOW WARNINGS;

How to load the sample database

The required database has been uploaded

  source C:\Users\VIGHNESH SUDHAKAR\Desktop\MySQL\mysqlsampledatabase.sql

Use the SHOW DATABASES command to list all databases in the current server

show databases;