U6697Sws

1CREATE TABLE IF NOT EXISTS clienti
2(
3    customer_id serial PRIMARY KEY,
4    cognome     varchar(30) not null,
5    nome        varchar(30) not null
6);
7CREATE TABLE IF NOT EXISTS pagamenti
8(
9    customer_id serial PRIMARY KEY,
10    importo     float not null
11);
12
13insert into clienti(cognome, nome)
14values ('Rossi', 'Mario'),
15       ('Verdi', 'Giacomo'),
16       ('Bianchi', 'Alex');
17insert into pagamenti(importo)
18values (10.95),
19       (25.95);
20
21SELECT *
22from clienti as a
23where a.customer_id not in (select customer_id from pagamenti);
24
25
26