User:A3nm/SD202 2021 ex2

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In this second exercise, we will query three tables: movie, casting, and actor.

The movie table describes movies, and contains the following fields:

  • id int(11), an identifier
  • title varchar(50), the title of the movie
  • yr int(11), the year the movie was released
  • director int(11), the identifier of the director
  • budget int(11), the movie's budget (we will not use it)
  • gross int(11), the movie's gross revenue (we will not use it)

The actor table contains people (actors and directors) and contains the following fields:

  • id int(11), an identifier
  • name varchar(50), the name of the person

The casting describes actors starring in movies. It contains the following fields:

  • movieid int(11), the identifier of the movie in the movie table
  • actorid int(11), the identifier of the actor in the actor table
  • ord int(11), an integer describing the position of the actor in the film's starring list. The first actor (called the leading actor) has ord value 1, the second actor has ord value 2, and so on.

For instance, here are the first 5 movies of the movie table:

idtitleyrdirectorbudgetgross
10001$19713
10002"Crocodile" Dundee198619328203506
10003"Crocodile" Dundee II19883615800000239606210
10004'Til There Was You19974910000000
10005'Til We Meet Again194065

Here are the casting rows corresponding to movie 10001:

movieidactoridord
1000141
1000152
1000163
1000174
1000185
1000196
10001107
10001118
10001129
100011310
100011411
100011512
100011613
100011714
100011815

And here are the corresponding tuples in the actor table. Note that the name of the actor with id 6 has an encoding issue -- we will ignore these issues in the sequel.

idname
4Warren Beatty
5Goldie Hawn
6Gert Fröbe
7Robert Webber
8Scott Brady
9Arthur Brauss
10Robert Stiles
11Wolfgang Kieling
12Bob Herron
13Christiane Maybach
14Hans Hutter
15Monica Stender
16Horst Hesslein
17Wolfgang Kuhlman
18Klaus Schichan

Warning: Again, the table names are case-sensitive and must be written in lowercase.

Warning: The queries in this exercise may be slow to evaluate, which may cause the server to timeout. If you get the error "Lost connection to MySQL server during query", then please simply try again evaluating the query. If the problem persists, your query may not be efficient enough and may need to be optimized. To debug it and get partial results, try adding some additional selection conditions and/or a LIMIT.

Basic joins

Compute the title of every Star Wars movie (starting with "Star Wars") and the name of its director. Sort the result by title.

SELECT title FROM movie WHERE title LIKE 'Star Wars%'
ORDER BY title
SELECT title, name FROM movie, actor WHERE title LIKE 'Star Wars%' AND director = actor.id
ORDER BY title

Compute the list of the names of the actors starring in the movie "Jurassic Park" (1993), in the order in which they starred (i.e., by increasing ord value).

SELECT * FROM movie WHERE title = 'Jurassic Park'
SELECT name FROM movie,actor,casting WHERE movie.id = casting.movieid AND
actor.id = casting.actorid AND title = 'Jurassic Park' ORDER BY ord


Compute the list of the titles of the movies where "George Clooney" appeared, ordered by title.

SELECT * FROM actor WHERE name = 'George Clooney'
SELECT title FROM movie,actor,casting WHERE movie.id = casting.movieid AND
actor.id = casting.actorid AND name = 'George Clooney'
ORDER BY title


Compute the list of the titles of all movies from 1920 together with the name of their leading actor (the one with ord value of 1), ordered by title.

SELECT * FROM movie
SELECT title, name FROM movie, casting, actor WHERE yr = 1920 AND
casting.movieid = movie.id AND casting.actorid = actor.id AND ord=1
ORDER BY title

Advanced joins

Compute the list of the titles of all movies from 1920 together with the name of their leading actor and with the name of their director, ordered by title.

SELECT * FROM movie
ORDER BY title
SELECT title, SA.name, D.name FROM movie, casting, actor as SA, actor as D
  WHERE yr = 1920 AND casting.movieid = movie.id AND casting.actorid = SA.id AND ord=1 AND D.id = director
ORDER BY title


Compute the five movies in the database having the highest number of participating actors, and this number of participating actors, sorted by decreasing number of actors. Warning: beware of titles like "The Hunchback of Notre Dame" that are the titles of multiple movies!

SELECT title, COUNT(*) AS cnt FROM movie, casting WHERE casting.movieid = movie.id GROUP BY movie.id, title ORDER BY cnt DESC LIMIT 5

Compute the years where the actor "Rock Hudson" participated to strictly more than one movie, along with the number of movies to which he participated on that year, sorted by decreasing number of movies, then by ascending year.

SELECT yr, COUNT(*) AS count FROM movie, casting, actor WHERE movie.id = casting.movieid AND
actor.id = casting.actorid AND name = 'Rock Hudson' GROUP BY yr HAVING count > 1
ORDER BY COUNT(*) DESC, yr


Compute the names of actors who were the leading actor in a movie where Harrison Ford appeared (and were not Harrison Ford himself). Order the results by actor name.

SELECT DISTINCT A2.name FROM actor AS A1, actor AS A2, casting AS C1, casting as C2 WHERE A1.name = 'Harrison Ford' AND A1.id = C1.actorid AND C1.movieid = C2.movieid AND C2.actorid = A2.id AND C2.ord = 1 AND A2.name <> 'Harrison Ford'
ORDER BY A2.name


Compute the titles of movies which were both directed by Woody Allen and had Woody Allen appear as an actor, sorted in alphabetical order.

SELECT title FROM movie, actor, casting WHERE casting.movieid = movie.id AND
casting.actorid = actor.id AND actor.name = 'Woody Allen' AND movie.director =
actor.id ORDER BY title


Compute the titles of movies which were directed by Woody Allen or had Woody Allen appear as an actor (or both), sorted in alphabetical order.

SELECT title FROM movie, actor, casting WHERE casting.movieid = movie.id AND
casting.actorid = actor.id AND actor.name = 'Woody Allen'
UNION
SELECT title FROM movie, actor WHERE movie.director = actor.id AND actor.name =
'Woody Allen'
ORDER BY title


In which movie title did Alain Delon and Catherine Deneuve appear together?

SELECT title FROM movie,casting AS C1, casting AS C2, actor AS A1, actor AS A2 WHERE A1.id = C1.actorid AND A2.id = C2.actorid AND C1.movieid = movie.id AND C2.movieid = movie.id AND A1.name = 'Alain Delon' AND A2.name = 'Catherine Deneuve'


Find the only actor who appeared in all Star Wars movies. (Note: this query is complex; if you get an error about losing connection to the server, please try again.)

SELECT name FROM actor WHERE NOT EXISTS (
  SELECT id FROM movie WHERE TITLE LIKE 'Star Wars%' AND NOT EXISTS (
    SELECT * FROM casting WHERE movieid=movie.id AND actorid=actor.id))


Find the only actor which only appeared in movies where Harrison Ford appeared, and appeared in strictly more than one movie.

SELECT name FROM actor, casting, movie WHERE casting.actorid = actor.id AND casting.movieid = movie.id AND name <> 'Harrison Ford' AND NOT EXISTS (
  SELECT id FROM movie, casting AS C1 WHERE C1.movieid = movie.id AND C1.actorid = actor.id AND NOT EXISTS
    (SELECT 1 FROM casting AS C2, actor AS A2 WHERE A2.name = 'Harrison Ford' AND C2.actorid = A2.id AND C2.movieid = C1.movieid)) GROUP BY name HAVING COUNT(movie.id) > 1


For performance reasons, we limit ourselves to the movies released no later than 1930, and to the actor names starting with A, B, or C. We say that two actors X and Y are challengers if X was the leading actor in a movie where Y appeared and Y was the leading actor in a movie where X appeared. Compute all pairs X, Y of challengers (with X < Y, in alphabetical order of X and then of Y).

WITH oldmov AS (SELECT id, yr FROM movie WHERE yr <= 1930),
aactor AS (SELECT id, name FROM actor WHERE name LIKE 'A%' OR name LIKE 'B%' OR name LIKE 'C%')
SELECT DISTINCT A1.name, A2.name FROM aactor AS A1, aactor AS A2, casting AS C1a, casting AS C1b, casting AS C2a, casting AS C2b, oldmov AS Ma, oldmov AS Mb WHERE A1.id = C1a.actorid AND A1.id = C1b.actorid AND A2.id = C2a.actorid AND A2.id = C2b.actorid AND C1a.movieid = C2a.movieid AND C1b.movieid = C2b.movieid AND C1a.ord = 1 AND C2b.ord = 1 AND C1a.movieid = Ma.id AND C1b.movieid = Mb.id AND A1.name < A2.name
ORDER BY A1.name, A2.name

Acknowledgements

This exercise is inspired by the exercises More_JOIN_operations and by R. Ramakrishnan, J. Gehrke. Database Management Systems, 3rd ed., 2002. Exercise 4.3. If you reach the end of this exercise and still have time, you can complete the questions in the other JOIN tutorials which were not covered here.

Thanks to Andrew Cumming for his great work in maintaining SQLZoo!