6R9DTDgE

1DROP TABLE  if exists printers, type_of_printer;
2
3CREATE TABLE printers
4(
5    id              serial unique,
6    exist           int,
7    cost_price      float,
8    cost            float,
9    characteristics int
10);
11CREATE TABLE type_of_printer
12(
13    model      text NOT NULL CHECK ( model IN ('Printer All-in-One', 'Printer')),
14    print_type text NOT NULL CHECK ( print_type IN ('jet', 'laser')),
15    number_colors int NOT NULL CHECK ( number_colors IN (4,6)),
16    size_paper text NOT NULL,
17    brand text NOT NULL
18);