Skip to content

Introduction to SQL

Here you can access the books table used in the course.

Take Notes

Add notes about the concepts you've learned and SQL cells with queries you want to keep.

A record is a row in a table field a is a cell in the table. Should be singular, in lowercase and no white spaces Unique identifier, - used to identify a record in a table, they area unique and often number. Table topics should remain separated.

DATA

Data types: number(interger, float), text, dates (take diferent amounts of storahe). Database schema - shows the database design and what data type can be hold.

Introducing queries

Keywords:

  • Select
  • FROM (the reference from the table). End the query with a ;

Versions

Free and paid, the majority of keywords are shared. Additional features

  • PostgreSQL: free and open-souce relational database
  • SQL Server: free and paid

LIMIT (To test the number of results)

Explore Datasets

Use the books table to explore the data and practice your skills!

  • Select only the title column.
  • Alias the title column as book_title.
  • Select the distinct author names from the author column.
  • Select all records from the table and limit your results to 10.
Spinner
DataFrameas
books
variable
-- Add your own queries here
SELECT *
FROM books