Introduction to SQL and Its Fundamentals: Lets talk with databases

5 min readJun 24, 2024

Introduction

SQL, pronounced “sequel” or “S-Q-L,” stands for Structured Query Language. It’s a powerful tool used to communicate and manipulate databases. Whether you’re managing a small set of data or handling massive databases, SQL is essential.

This blog will introduce you to SQL and its fundamental concepts in a simple, easy-to-understand way.

What is SQL?

SQL is a programming language used to manage and manipulate relational databases. It allows you to create, read, update, and delete data.

Think of SQL as a language that helps you talk to a database and ask it questions about the data it stores.

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Imagine you have a big collection of books in a library. You want to be able to find specific books quickly, add new books, remove old ones, or even get a list of all books by a particular author. SQL, which stands for Structured Query Language, is like a librarian who helps you do all these tasks in an efficient and organized way.

Why Learn SQL?

SQL is a crucial skill in the data industry. Here’s why learning SQL is beneficial:

Here is the Truth,

Be it Building smart analytics dashboard in Tableau or PowerBI , Cleaning a Data in ETL tools or Automating the tasks in Alteryx, Airflow, Python Scripts or Be building a Machine Learning algorithm we always need a data which resides on Cloud platforms like Oracle, Snowflake, AWS, Redshift etc and its only and only SQL who can communicate with such platforms and connect with tools mentioned above to accomplish the tasks because you never with Excel files in a reality.

So in nutshell you choose to be in DataAnalytics, DataEngineer, Datascientist, or any fancy AI job you will always need to run SQL queries to extract the data from the databases.Hence SQL is a heart.

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Universality: SQL is used across various industries and is compatible with many database systems like MySQL, PostgreSQL, SQL Server, and SQLite.
High Demand: SQL skills are highly sought after in data-related roles.
Efficiency: SQL makes data manipulation easy and efficient, allowing for complex data analysis with simple commands.

A Short History of SQL

OR

Early Beginnings

1970: Edgar F. Codd proposes the relational model for databases.
1974–1975: IBM researchers Donald D. Chamberlin and Raymond F. Boyce develop SEQUEL (Structured English Query Language) to implement Codd’s relational model.

Transition to SQL

1979: Oracle releases Oracle V2, the first commercial implementation of SEQUEL, now renamed SQL due to trademark issues.

Standardization

1986: The American National Standards Institute (ANSI) adopts SQL as the standard language for relational database management systems.
1987: The International Organization for Standardization (ISO) also standardizes SQL.

Evolution and Growth

1990s to Present: SQL evolves with new features, including support for triggers, stored procedures, and handling XML and JSON data. Various database systems adopt and expand SQL capabilities, cementing its place in data management.

SQL’s journey from a research project at IBM to an industry-standard language highlights its importance in the world of data.

Basic SQL Commands

SQL commands are often referred to as CRUD operations: Create, Read, Update, and Delete. These commands form the foundation of working with databases.

A Quick Refresher on All the Commonly used SQL Commands!

1. SELECT: Reading Data

The SELECT statement is used to retrieve data from a database. It is one of the most frequently used SQL commands.

Example:

SELECT * FROM Employees;

This query retrieves all columns from the Employees table.

2. INSERT: Adding Data

The INSERT INTO statement is used to add new records to a table.

Example:

INSERT INTO Employees (FirstName, LastName, Department, Salary)
VALUES ('John', 'Doe', 'Sales', 50000);

3. UPDATE: Modifying Data

The UPDATE statement is used to modify existing records in a table.

Example:

UPDATE Employees
SET Salary = 55000
WHERE FirstName = 'John' AND LastName = 'Doe';

4. DELETE: Removing Data

The DELETE statement is used to remove records from a table.

Example:

DELETE FROM Employees
WHERE LastName = 'Doe';

Summary of Command Types

CREATE: DDL command used to define and create new database objects.
INSERT: DML command used to add new data into a table.
UPDATE: DML command used to modify existing data in a table.
DELETE: DML command used to remove data from a table.

These commands form the foundation of interacting with a database, allowing you to define its structure and manage the data it contains.

Conclusion

SQL is an essential tool for managing and manipulating data in relational databases. Its history shows how it has evolved into a standardized and widely used language.

By learning SQL, you gain the ability to efficiently handle data through basic commands like SELECT, INSERT, UPDATE, and DELETE. Whether you’re a beginner or an experienced data professional, SQL is a valuable skill that opens up numerous opportunities in the data industry.

Happy Learning!