Yurttas/PL/DBL/postgres/F/01/PC/q13.sql

 1/*
 2REM
 3REM q13.sql
 4REM
 5REM Delete all Laptops made by a manufacturer that doesn't make
 6REM printers.
 7REM
 8*/
 9
10SELECT current_schema();
11SET search_path to "pc";
12
13DELETE FROM Product
14WHERE type='laptop'
15  AND maker NOT IN (SELECT maker
16		    FROM Product
17		    WHERE type='printer');
18
19DELETE FROM Laptop
20WHERE model NOT IN (SELECT model
21                    FROM Product);