SQL query practice : 6002526

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SQL query practice : (6002526)

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Lesson 1 : SELECT queries 101

1. Find the title of each film

SELECT title FROM movies;

2. Find the director of each film

SELECT director FROM movies;

3. Find the title and director of each film

SELECT title, director FROM movies;

4. Find the title and year of each film

SELECT title, year FROM movies;

5. Find all the information about each film

SELECT * FROM movies;

Lesson 2 : Queries with constraints (Pt. 1)

1. Find the movie with a row id of 6

SELECT * FROM movies WHERE id = 6;

2. Find the movies released in the years between 2000 and 2010

SELECT * FROM movies WHERE year BETWEEN 2000 AND 2010;

3. Find the movies not released in the years between 2000 and 2010

SELECT * FROM movies WHERE year NOT BETWEEN 2000 AND 2010;

4. Find the first 5 Pixar movies and their release year

SELECT * FROM movies WHERE year LIMIT 5;

Lesson 3 : Queries with constraints (Pt. 2)

1. Find all the Toy Story movies

SELECT title FROM movies WHERE title LIKE "Toy Story%";

2. Find all the movies directed by John Lasseter

SELECT title FROM movies WHERE director = "John Lasseter";

3. Find all the movies (and director) not directed by John Lasseter

SELECT title FROM movies WHERE director != "John Lasseter";

4. Find all the WALL-* movies

SELECT title FROM movies WHERE title LIKE "WALL-%"

Lesson 4 : Filtering and sorting Query results

1. List all directors of Pixar movies (alphabetically), without duplicates

SELECT DISTINCT director FROM movies ORDER BY director;

2. List the last four Pixar movies released (ordered from most recent to least)

SELECT DISTINCT title FROM movies ORDER BY year DESC LIMIT 4;

3. List the first five Pixar movies sorted alphabetically

SELECT title FROM movies ORDER BY title LIMIT 5;

4. List the next five Pixar movies sorted alphabetically

SELECT title FROM movies ORDER BY title LIMIT 5 OFFSET 5;

Lesson 5 : Review Simple SELECT Queries

1. List all the Canadian cities and their populations

SELECT city, population
FROM north_american_cities
WHERE country = "Canada";

2. Order all the cities in the United States by their latitude from north to south

SELECT city
FROM north_american_cities
WHERE country = "United States"
ORDER BY latitude DESC;

3. List all the cities west of Chicago, ordered from west to east

SELECT city
FROM north_american_cities
WHERE longitude < -87.629798
ORDER BY longitude;

4. List the two largest cities in Mexico (by population)

SELECT city
FROM north_american_cities
WHERE country = "Mexico"
ORDER BY population DESC
LIMIT 2;

5. List the third and fourth largest cities (by population) in the United States and their population

SELECT city
FROM north_american_cities
WHERE country = "United States"
ORDER BY population DESC
LIMIT 2 OFFSET 2;

Lesson 6 : Multi-table queries with JOINs

1. Find the domestic and international sales for each movie

SELECT title, domestic_sales, international_sales
FROM movies
INNER JOIN boxoffice
    ON movies.id = boxoffice.movie_id;

2. Show the sales numbers for each movie that did better internationally rather than domestically

SELECT title, domestic_sales, international_sales
FROM movies
INNER JOIN boxoffice
    ON movies.id = boxoffice.movie_id
WHERE international_sales > domestic_sales;

3. List all the movies by their ratings in descending order

SELECT title, rating
FROM movies
INNER JOIN boxoffice
    ON movies.id = boxoffice.movie_id
ORDER BY rating DESC;

Lesson 7 : OUTER JOINs

1. Find the list of all buildings that have employees

SELECT DISTINCT building FROM employees;

2. Find the list of all buildings and their capacity

SELECT * FROM buildings;

3. List all buildings and the distinct employee roles in each building (including empty buildings)

SELECT DISTINCT building_name, role
FROM buildings
LEFT JOIN employees
    ON building_name = employees.building;

Lesson 8 : A short note on NULLs

1. Find the name and role of all employees who have not been assigned to a building

SELECT name, role FROM employees WHERE building IS NULL;

2. Find the names of the buildings that hold no employees

SELECT DISTINCT building_name
FROM buildings
LEFT JOIN employees
    ON building_name = employees.building
WHERE employees.building IS NULL;

Lesson 9 : Queries with expressions

1. List all movies and their combined sales in millions of dollars

SELECT DISTINCT
    title,
    (domestic_sales + international_sales) / 1000000 AS sales
FROM movies
INNER JOIN boxoffice
    ON movies.id = boxoffice.movie_id;

2. List all movies and their ratings in percent

SELECT DISTINCT
    title,
    (rating * 10) AS rate_percent
FROM movies
INNER JOIN boxoffice
    ON movies.id = boxoffice.movie_id;

3. List all movies that were released on even number years

SELECT title FROM movies WHERE year % 2 = 0;

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Review 1 — Tasks
3. SELECT * FROM north_american_cities where longitude < -87.629798
ORDER BY longitude asc;

Great Job!

Thank you it's useful to practice.

great work bro