For an instructor lead, in-depth look at learning SQL click below.
Welcome to this beginner’s tutorial on SQL! In this guide, we’ll introduce to you the basics of SQL – a standard language designed for managing data in relational database management systems. No need to worry if you are a complete beginner, as we will start with the very basics. By the end of this tutorial, we promise you’ll be able to create and manipulate your own databases. Let’s start!
What is SQL?
SQL, an acronym for Structured Query Language, is a coding language used to communicate with and manipulate databases. It is notably used to create, delete, fetch and modify database records. Not just that, you can also create and delete databases and tables with SQL.
Basic SQL Commands
There are several SQL commands which you should know to interact with a database. The most basic ones include SELECT, INSERT, UPDATE, DELETE, CREATE, and DROP. Let’s take a look at few of them:
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/* The SELECT command is used to select data from a database.*/ SELECT * FROM Customers; /* The INSERT INTO command is used to insert new data into a database.*/ INSERT INTO Customers (CustomerName, ContactName, Country) VALUES ('Cardinal', 'Tom B. Erichsen', 'Norway'); /*The UPDATE command is used to modify records in a database.*/ UPDATE Customers SET ContactName='Alfred Schmidt', City='Hamburg' WHERE CustomerName='Alfreds Futterkiste'; /* The DELETE command is used to delete existing records in a database. */ DELETE FROM Customers WHERE CustomerName='Alfreds Futterkiste'; |
Creating a database
Creating a new database is very straightforward in SQL. The general command structure is as follows:
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CREATE DATABASE database_name; |
Adding tables to your database
Once you have your database, you can start adding tables to it. The general command structure for creating a new table called ‘Employee’ can be represented as:
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CREATE TABLE Employee( ID INT PRIMARY KEY NOT NULL, NAME TEXT NOT NULL, AGE INT NOT NULL, ); |
Wrapping up
This tutorial just scratches the surface of what is possible with SQL. SQL is a powerful language that can simplify a wide range of tasks related to data manipulation and analysis. Once comfortable with the basics, we encourage you to explore more commands and practice SQL with real world databases. Stay tuned for our next tutorial where we get deeper into SQL!