The cinema wants a list of how many seats each movie sold (seats added up). The starter's LEFT JOIN already keeps the movies with no tickets, but their total comes out empty; make it 0. Pick title and the seat count.
The tables
movies
id
title
genre
minutes
rating
1
Robot Summer
family
95
8
2
Dark Lake
horror
110
6
3
Space Pals
family
88
7
4
The Long Road
drama
142
9
5
Laugh Track
comedy
101
5
6
Snow Day
comedy
92
7
6 rows
tickets
id
movie_id
day
seats
price
1
1
Fri
2
40
2
1
Sat
4
80
3
2
Fri
1
25
4
3
Sat
3
54
5
4
Sun
2
60
6
1
Sun
1
20
7
5
Sat
2
36
8
3
Sun
5
90
8 rows
movies
id
title
genre
minutes
rating
1
Robot Summer
family
95
8
2
Dark Lake
horror
110
6
3
Space Pals
family
88
7
4
The Long Road
drama
142
9
5
Laugh Track
comedy
101
5
6
Snow Day
comedy
92
7
6 rows
tickets
id
movie_id
day
seats
price
1
1
Fri
2
40
2
1
Sat
4
80
3
2
Fri
1
25
4
3
Sat
3
54
5
4
Sun
2
60
6
1
Sun
1
20
7
5
Sat
2
36
8
3
Sun
5
90
8 rows
query.sql
SELECT movies.title,
-- your code here: wrap SUM(tickets.seats) in COALESCE(…, 0)
SUM(tickets.seats)
FROM movies
LEFT JOIN tickets ON tickets.movie_id = movies.id
GROUP BY movies.title;
Ctrl + Enter runs too
Result
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