Query 1.) Theaters showing movies directed by T.
------------------------------------------------
SQL version:

SELECT s.theater 
FROM   Schedule s, Movie m 
WHERE  s.mtitle = m.title AND 
       m.director='Tarantino'


Algebra version:

proj_{theater}(Schedule 
               join_{mtitle=title} 
               (select_{dir='Tarantino'}(Movie)))



Query 2.) Theaters not showing any movies directed by T.
--------------------------------------------------------
SQL version with "not exists":

SELECT s1.theater 
FROM   Schedule s1 
WHERE  not exists (SELECT * 
       	   	   FROM   Schedule s2, Movie m 
		   WHERE  s2.theater=s1.theater AND 
		          s2.mtitle = m.title AND 
			  m.director='Tarantino')


SQL version with "not in":

SELECT s1.theater 
FROM   Schedule s1 
WHERE  s1.theater not in (SELECT s2.theater 
       	   	          FROM   Schedule s2, Movie m 
	                  WHERE  s2.mtitle = m.title AND 
			         m.director='Tarantino')

SQL version with "MINUS":

(SELECT s.theater 
 FROM   Schedule s)
MINUS
(SELECT s.theater
 FROM   Schedule s, Movie m 
 WHERE  s.mtitle = m.title AND 
	m.director='Tarantino')



Algebra version:

proj_{theater}(Schedule)
       \ proj_{theater}(Schedule 
                        join_{mtitle=title} 
		        (select_{dir='Tarantino'}(Movie)))




Query 3.) Theaters showing only movies directed by T.
-----------------------------------------------------
SQL version with "not exists":

SELECT s.theater
FROM   Schedule s
WHERE  not exists (SELECT *
                   FROM  Schedule s1
                   WHERE s1.theater = s.theater AND
                         not exists (SELECT *
                                     FROM   Movie m
                                     WHERE  s1.mtitle = m.title AND
				            m.director = 'Tarantino'))

SQL version with "not in": 

SELECT s.theater
FROM   Schedule s
WHERE  s.theater not in (SELECT s1.theater
                         FROM   Schedule s1
                         WHERE  s1.mtitle not in (SELECT m.title
                                                  FROM   Movie m
                                                  WHERE  m.director = 'Tarantino'))

Algebra version:

proj_{theater}(Schedule)
       \ proj_{theater}(Schedule 
                        \ (proj_{theater}(Schedule) 
                           X 
                           proj_{title}(select_{dir='T'}(Movie))))



Query 4.) Theaters showing all movies directed by T.
----------------------------------------------------
Bad theaters: Not showing some movie directed by T.,
              i.e., where some T. movie is not on schedule.


SELECT s.theater
FROM   Schedule s
WHERE  not exists (SELECT *
                   FROM   Movie m
                   WHERE  m.director = 'Tarantino' and
		          not exists (SELECT *
			              FROM   Schedule s0
				      WHERE  s0.theater = s.theater and
				             s0.mtitle = m.title))

Algebra version:

  proj_{theater}(Schedule)
  \
  proj_{theater}((proj_{theater}(Schedule) 	          
                  X
                  proj_{title}(select_{dir='T'}(Movie)))
                  \
		  Schedule)