Exercise 1.
1.  select Title, PubName from Book;

2.  select * from Book where PagesNum = (select max(PagesNum) from Book);


3.  select Author from Book group by Author having count(*) > 5;

4.  select * from Book where PagesNum > (select avg(PagesNum) * 2 from Book);

5.  select c1.CategoryName from Category c1 where exists(select * from Category c2 where c2.ParentCat = c1.CategoryName);


6.  select Author, count(*) as CountOfBooks from Book group by Author order by CountOfBooks desc limit 1;

7.  -

8.  select b.* from Book b inner join Copy c group by b.ISBN having count(*) > 1;

9.  select b.* from Book b where (select count(*) from Book b2 where b2.PubYear <= b.PubYear) < 10 order by b.PubYear;

10. -

Exercise 2.
1.  insert into Borrowing (ReaderNr, ISBN, CopyNumber, ReturnDate) select ID, 123456, 4, null from Reader where (LastName = 'Johnson' AND FirstName = 'John');

2.  delete from Book where PubYear > 2000;

3.  update Borrowing b, BookCat bc set ReturnDate = ReturnDate + interval 30 day where b.ReturnDate >= '20160101' and b.ISBN = bc.ISBN and bc.CategoryName = 'Databases';