For an instructor lead, in-depth look at learning SQL click below.
Welcome to the world of SQL! This handy beginner’s guide will take you through the basics of this powerful, versatile language used in the vast realm of data analytics.
Introduction to SQL
Structured Query Language (SQL) is a language used to view or change data in databases. The sentences used in SQL are called queries. With SQL, you can create databases, tables, and manipulate the data within.
Creating a Database
To start, you will need a database. Here’s how you create a database in SQL:
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CREATE DATABASE DatabaseName; |
This will create a new database called ‘DatabaseName’. Remember to replace ‘DatabaseName’ with the name of your database.
Creating Table
Next, we create a table within our database. For example, let’s create a table named ‘Students’ with columns ‘StudentId’, ‘Name’ and ‘Major’:
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CREATE TABLE Students ( StudentId INT, Name VARCHAR(255), Major VARCHAR(255) ); |
Inserting Data
Now that we have our table created, let’s insert some data into our ‘Students’ table:
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INSERT INTO Students (StudentId, Name, Major) VALUES (1, 'John Doe', 'Computer Science'); |
This will create a new record in ‘Students’ where ‘StudentId’ is 1, ‘Name’ is ‘John Doe’, and ‘Major’ is ‘Computer Science’.
Selecting Data
Now, how do we view the data we’ve stored? Using a SELECT statement, we can view all the records in our ‘Students’ table:
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SELECT * FROM Students; |
The asterisk (*) is a wildcard character that tells SQL we want to select all columns.
Conclusion
SQL is a powerful tool in the realm of data analytics. With it, you can store, manipulate, and analyze data with ease. This guide has provided the groundwork for your journey towards mastering SQL. Happy querying!