Please help me explain. multi-table Joint Check. I don't understand it, thank you.

Please help me explain, multi-table join, I do not understand, thank you SQLcodeselect * from (selectbookid, count (bookid) asdegreefromtb_borrowgroupbybookid) asborrjoin (selectb. *, c. nameasbookcasename, p. pubname, t. typ, please help me explain. multi-table join queries are not easy to understand. thank you.

SQL code

  select * from (select bookid,count(bookid) as degree from tb_borrow group by bookid) as borr join (select b.*,c.name as bookcasename,p.pubname,t.typename from tb_bookinfo b left join tb_bookcase c on b.bookcase=c.id join tb_publishing p on b.ISBN=p.ISBN join tb_booktype t on b.typeid=t.id where b.del=0) as book on borr.bookid=book.id order by borr.degree desc limit 10 

Please help me explain. multi-table join queries are not easy to understand. thank you.

------ Solution --------------------

SQL code

select * from     (        select bookid,count(bookid) as degree from tb_borrow group by bookid    )as borr join       (         select b.*,c.name as bookcasename,p.pubname,t.typename from tb_bookinfo b left join tb_bookcase c on b.bookcase=c.id join tb_publishing p on b.ISBN=p.ISBN join tb_booktype t on b.typeid=t.id where b.del=0      ) as book on borr.bookid=book.id order by borr.degree desc limit 10