Codecademy will be down from 00:00 to 02:00 ET on November 15, 2019 for scheduled database maintenance. This will affect the website, learning environment, forums, and mobile app. We will provide updates as necessary.
Cheat Sheets are in BETA. Give us your feedback.

SELECT Statement

The SELECT * statement returns all columns from the provided table in the result set. The given query will fetch all columns and records (rows) from the movies table.

SELECT * FROM movies;

AS Clause

Columns or tables in SQL can be aliased using the AS clause. This allows columns or tables to be specifically renamed in the returned result set. The given query will return a result set with the column for name renamed to movie_title.

SELECT name AS 'movie_title' FROM movies;

DISTINCT Clause

Unique values of a column can be selected using a DISTINCT query. For a table contact_details having five rows in which the city column contains Chicago, Madison, Boston, Madison, and Denver, the given query would return:

  • Chicago
  • Madison
  • Boston
  • Denver
SELECT DISTINCT city FROM contact_details;

WHERE Clause

The WHERE clause is used to filter records (rows) that match a certain condition. The given query will select all records where the pub_year equals 2017.

SELECT title FROM library WHERE pub_year = 2017;

LIKE Operator

The LIKE operator can be used inside of a WHERE clause to match a specified pattern. The given query will match any movie that begins with Star in its title.

SELECT name FROM movies WHERE name LIKE 'Star%';

_ Wildcard

The _ wildcard can be used in a LIKE operator pattern to match any single unspecified character. The given query will match any movie which begins with a single character, followed by ove.

SELECT name FROM movies WHERE name LIKE '_ove';

% Wildcard

The % wildcard can be used in a LIKE operator pattern to match zero or more unspecified character(s). The example query will match any movie that begins with The, followed by zero or more of any characters.

SELECT name FROM movies WHERE name LIKE 'The%';

NULL Values

Column values in SQL records can be NULL, or have no value. These records can be matched (or not matched) using the IS NULL and IS NOT NULL operators in combination with the WHERE clause. The given query will match all addresses where the address has a value or is not NULL.

SELECT address FROM records WHERE address IS NOT NULL;

BETWEEN Operator

The BETWEEN operator can be used to filter by a range of values. The range of values can be text, numbers or date data. The given query will match any movie made between the years 1980 and 1990, inclusive.

SELECT * FROM movies WHERE year BETWEEN 1980 AND 1990;

AND Operator

The AND operator allows multiple conditions to be combined. Records must match both conditions that are joined by AND to be included in the result set. The example query will match any car that is blue and made after 2014.

SELECT model FROM cars WHERE color = 'blue' AND year > 2014;

OR Operator

The OR operator allows multiple conditions to be combined. Records matching either condition joined by the OR are included in the result set. The given query will match customers whose state is either ca or ny.

SELECT name FROM customers WHERE state = "ca" OR state = "ny";

ORDER BY Clause

The ORDER BY clause can be used to sort the result set by a particular column either alphabetically or numerically. It can be ordered in ascending (default) or descending order with ASC/DESC. In the example, all the rows of the contacts table will be ordered by the birth_date column in descending order.

SELECT * FROM contacts ORDER BY birth_date DESC;

LIMIT Clause

The LIMIT clause is used to narrow, or limit, a result set to the specified number of rows. The given query will limit the result set to 5 rows.

SELECT * FROM movies LIMIT 5;