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Roadmap to learn SQL for Beginners

TABLE OF CONTENTS

 

 

I. WHAT IS SQL AND WHY IS IT IMPORTANT TO LEARN SQL?

SQL stands for Standard Query Language, and it is the language for accessing and dealing with different databases. ANSI defines SQL as "the standard language for RDMS." SQL allows one to delete, update, search and modify data from a database. Some of the standard RDMS that use SQL are- Oracle, Sybase, Microsoft SQL Server, Access, Ingres, etc. 

  • SQL allows its users to modify and access data in a database.
  • SQL lets you become more independent in data analyses.
  • As published in the 2021 Stack Overflow report, SQL is now the third most common language used for programming.
  • SQL lets one understand how data is structured (for instance, at your workplace).

 

II. STEPS TO LEARN SQL

  1. Know the Basic Concepts Of SQL
    The best way to start learning any language is to learn its basics. To start learning SQL you first need to learn the SQL commands. These are basically of four types- DDL, DML, DCL and TCL.
    The first two commands are required at the basic level whereas the other two are required at intermediate and advanced level. Read about these two commands below:
  • DDL (Data Definition Language): This contains commands for creating, modifying, and deleting databases, tables, columns, etc. 
  • DML (Data Manipulation Language): This contains queries to create or manipulate the actual data. 

    Read the basic DDL and DML SQL commands that you need to learn, and their uses below:
  1. SELECT- to extract data from any database
  2. UPDATE - to update data in any database
  3. DELETE - to delete data from any database
  4. INSERT INTO - to insert new data into any database
  5. CREATE DATABASE - to create a new database
  6. ALTER DATABASE - to modify a new database
  7. CREATE TABLE - to create a new table
  8. ALTER TABLE - to modify/alter a table
  9. DROP TABLE - to delete a table
  10. CREATE INDEX - to create an index (search key)
  11. DROP INDEX - to delete an index

 

  1. Learn about the common data types that are used in SQL.
    Next, you need to learn about the data types that we use in SQL. Under this you need to learn about standard data types such as:
  1. INT
  2. VARCHAR
  3. FLOAT
  4. DATE and TIME
  5. You can also have user-defined data types based on predefined SQL types.

 

  1. Learn about the different types of Constraints
    There are various constraints that can be used while creating tables in SQL. You must learn about the below-mentioned constraints to learn SQL.
  1. UNIQUE
  2. PRIMARY KEY
  3. FOREIGN KEY
  4. NOT NULL
  5. CHECK   
  6. DEFAULT etc.

 

  1. Learn about the various built-in functions in SQL
    While writing a SQL query you will be required to use certain built-in functions. The SQL functions that you must be through with are:
  1. SORT() 
  2. LOWER() 
  3. ABS() 
  4. YEAR() 
  5. CONCAT() 
  6. MAX() 
  7. AVG()
  8. COUNT()
  9. SUM()
    Once you have mastered the basic SQL concepts, it's time to take your learning to the next level. After you have built a strong foundation, you are now ready to learn the advanced concepts of SQL. Read about all this in this segment of the article.

 

  1. Learn about the SQL DCL (Data Control Language) and TCL (Transaction Control Language) commands.
    You will require the Transaction Control Language (TCL) commands to manage transactions in the database. With the help of TCL commands, SQL statements can be grouped together into logical transactions. The three TCL commands that you need to learn are.
  1. COMMIT
  2. SAVEPOINT
  3. ROLLBACK

The Data Control Language syntax is used to control access to data stored in a database (Authorization). Under this, you need to learn about the commands such as:

  1. GRANT
  2. REVOKE

Next, you need to have knowledge of several important concepts that are mentioned herein.

  1. Learn how to work with Nested Query and Repeated Data
     
  2. Learn what does CTE in SQL means
     
  3. Learn Database design: Under this, you need to learn two major components- Normalisation and ER Modelling
     
  4. Learn what is SQL Trigger
     
  5. Learn about SQL Processing
     
  6. Learn about concepts such Injection, Hosting, etc.
     
  7. Master SQL Server Architecture: This has three major components namely- Protocol Layer, Relational Engine and Storage Engine.
     
  8. Learn about the various SQL Process: There are different SQL engines which decide how to interpret a specific task. You need to learn about these SQL Process to master SQL. They are:-
  1. SQL Query Engine
  2. Optimization Engine
  3. Query Dispatcher
  4. Classic Query Engine
     

III. INSTALLATION AND USAGE OF SQL

Here are important steps about how to get SQL Server and how to install it. SQL Server is only available as a 64-bit application. You can read the required steps to install and use SQL below.

Installation:-

Step 1- You can download the Microsoft SQL server from the Official Microsoft Website.

Step 2- Select the developer edition.

Steps 3- Now press Download.

Step 4- During the installation process select there are three options Basic, Custom and Download Media. Select the Basic option.

Step 5- After accepting the agreements, install the server.

Step 6- Connect now and start to execute queries.

Usage:-

To use the SQL software we need some IDEs.

IDE is integrated development environment that allows managing all the application related files and working with all the types of packages and features. These are some top IDEs to use with SQL software:-

  1. DBeaver
  2. PHPMyAdmin
  3. Adminer

 

IV. WHERE CAN YOU LEARN SQL?

Before deciding the course for learning SQL, there are various things you must keep in mind. Select the course,

  • which provides clear knowledge in simple words.
  • which offer flexibility.
  • which allows you to learn at your own speed.
  • which is affordable.

There are various sources you can refer for learning SQL. Some of the free courses to learn SQL are mentioned here.

Free courses to learn SQL:-

Apart from the free courses, there are various paid courses as well that provide SQL Learning. These courses provide resources to learn and also provide test/quizzes to test your knowledge. Read some of the paid courses to learn SQL below:

Paid courses to learn SQL:-

 

V. BENEFITS OF LEARNING SQL

  • Access Multiple Records: SQL lets us access multiple records with just one command.
  • Data Dependence: Updating the records is easy.
  • Data Sharing: SQL lets us share data without any security risks.
  • Easy to learn: Syntax and learning are easy in comparison to other coding languages.
  • Handles large sets of data: Compared to excel and spreadsheet, SQL can store and handle large amounts of data.
  • Better insight into the datasets: SQL provides a good virtual relationship between the datasets to understand the data better.
  • Standardized: SQL has been standardized by both ISO and ANSI.

 

VI. PROJECT IDEAS FOR BEGINNERS FOR SQL

  1. Project on Library Management System

In this project, you need to build an online library management system. It would offer a user-friendly way of issuing books and viewing different books and titles available under a category. A library management system project has an entry for every book, mentioning who has issued it, the duration, and the fine, if any.

Click Here to check the Source Code for this project.

 

  1. Project on Hospital Management System

This SQL project is a web-based program that allows you to manage the operation of a hospital. It will contain a systematic record of patients, physicians, and rooms. These records will be accessed only by the administrator. All the patients will have a unique ID, linked to the database based on the treatments they are receiving.

Through the database the patients can also access records like the room number of a patient admitted, the doctor's availability time, and status of vacant beds.

Click Here to check the Source Code for this project.

 

  1. Project on Payroll Management System

The Payroll Management System Project is one of the most chosen SQL database project ideas due to its wide use across industries. The database will focus on generating output in the form of bank files and salary slips. A Tax file/ for the tax office will also be created and stored in the database. The database will compute the salaries based on the employee data (name, designation, pay scale, benefits, etc.) and attendance records also includes the leaves that are taken.

Click Here to check the Source Code for this project.

 

  1. Project on Online Retail Application Database

With the remarkable growth in e-commerce experiences, online retail application project has become very popular. The application permits the user to register and buy a commodity using the internet. The registration process generally requires the generation of a unique customer ID and password. A bill will always be prepared at the time the user purchases a commodity.

Click Here to check the Source Code for this project.

  1. Project on Electric Bill System Database

This Electric Bill System Database project on SQL is in high demand in electrical industries. It will have two sections- the client and the admin section. The user will first have to register to the client’s account to access the system. After this, they can check their bill of the month. They can also file a complaint regarding their bill. In the admin section, the user can print a billing invoice to the client and reply to the complaints recorded.

Click Here to check the Source Code for this project.

 

Here are some other project ideas for SQL and the respective source codes:

  1. SQL Project on Bank Accounts Management System
    Click Here for the source code.

     
  2. SQL Project on Voice-Based Transport Enquiry System
    Click Here for the source code.
     
  3. SQL Project on Wholesale Management System Database
    Click Here for the source code.

 

VII. TIME REQUIRED FOR LEARNING SQL

  • For learning the Basic Concepts you will require 1-2 months.
  • For learning the Advanced Concepts you will need approx. 4-5 weeks.

 

VIII. TIPS TO LEARN SQL

  • Find a proper and perfect online course for you based on the things mentioned above.
  • There are various websites that contain answers to most of the common questions that a beginner can face while learning SQL. You may refer these websites to solve your query while learning SQL. One such website is Stackoverflow
  • Choose your required database.
  • There are various free websites that lets you practice SQL queries on a database. To learn SQL you can use the websites mentioned below.
  1. sqlzoo
  2. hackerrank
  3. sqlbolt
  4. w3resource
  • Start using the queries and joins from the first day.
  • Ask your doubts without any hesitation.
  • Practice as much as you can.
  • Stick with only one course to study.

    ALL THE BEST!!!