SQL Basics – Introduction To SQL

We are going to learn SQL basics so you can grasp the core concept of SQL and databases.

The world is full of data. Every day we use apps that are full of data

On Instagram, they store data about who you are, what you like, your followers, photos you upload.

Every bak store data about how much money you have in the account, how much you owe to them (Loan), your daily transactions.

Do you ever wonder, how do these apps store data? Well, they use a database.

let’s be familiar with SQL basics.

What is the Database?

A database is a program that helps store data and provides functionality for adding, modifying and querying that data and doing that all fast.

A database is a collection of data organized in a manner that has the capability of storing information, through which a user can retrieve stored data effectively and efficiently when required.

A database is made up of tables that store relevant information.

SQL Basics - Introduction To SQL

For example, you would use a database, if you were to create a website like Facebook, which contains a lot of information like usernames, passwords, videos, images, comments and hundreds of other things.

A table stores and shows data in a structured format consisting of columns and rows that are similar to Excel spreadsheets.

Databases usually contain multiple tables, each designed for a specific purpose. For example, think about creating a database table of names and mobile numbers.

Databases come in many forms, but a really popular type of database is called a Relational Database.

What is Relational Database?

A relational database is a type of database that organizes data into one more tha one tables, and links them, based on defined relationships. These relationships enable you to retrieve and combine data from one or more tables with a single query.

SQL Basics - Introduction To SQL

A relational database allows data to be broken down into logical, smaller, manageable units, allowing for easier maintenance and providing more optimal database performance according to the level of the organization.

SQL Basics - Introduction To SQL

An image above shows an example of a relational database

The Artists and Albums tables are related. The Albums table has an ArtistId column that corresponds to the ArtistId in the Albums table.

In this case, the Artists table is the parent table (or primary table), and the Albums table is the child table.

This is how apps like Spotify and Apple Music help you find all the albums, Songs and playlists related to the Artist.

Again, tables are related in a relational database, allowing adequate data to be retrieved in a single query (although the desired data may exist in more than one table).

By having common keys, or fields, among relational database tables, data from multiple tables can be joined to form one large result set.

Most databases come with a Query language to interact with the database.

okay so these were some SQL basic concepts, In the following lessons, you will learn more about SQL.