SELECT concat(book.fk_Language, workOfWriters.fk_Language) as lox, count(*)
from (book INNER JOIN book_work ON book.pk_book=book_work.fk_book)
INNER JOIN workOfWriters ON workOfWriters.pk_workOfWriters=book_work.fk_workOfWriters
GROUP BY lox
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UPDATE issued INNER JOIN periodForBack
ON pk_periodForBack=fk_periodForBack
SET issued.dateActualReturn=adddate(issued.dateOfIssue,INTERVAL periodForBack.periodForBack day)

UPDATE issued INNER JOIN periodForBack
ON pk_periodForBack=fk_periodForBack
SET issued.dateActualReturn=adddate(issued.dateActualReturn,INTERVAL 2 day)
where pk_issued=2

UPDATE issued INNER JOIN periodForBack
ON pk_periodForBack=fk_periodForBack
SET issued.dateActualReturn=adddate(issued.dateActualReturn,INTERVAL 2 day)
where pk_issued=6

UPDATE issued INNER JOIN periodForBack
ON pk_periodForBack=fk_periodForBack
SET issued.dateActualReturn=adddate(issued.dateActualReturn,INTERVAL 2 day)
where pk_issued=7

UPDATE issued INNER JOIN periodForBack
ON pk_periodForBack=fk_periodForBack
SET issued.dateActualReturn=adddate(issued.dateActualReturn,INTERVAL 2 day)
where pk_issued=8
--------------------------------------------------------------------------------------
SELECT COUNT(*) as lox FROM
(book INNER JOIN book_work
 ON book.pk_book=book_work.fk_book)
INNER JOIN workOfWriters
ON book_work.fk_workOfWriters=workOfWriters.pk_workOfWriters
where book.fk_Language=workOfWriters.fk_Language
UNION SELECT COUNT(*) FROM
(book INNER JOIN book_work
 ON book.pk_book=book_work.fk_book)
INNER JOIN workOfWriters
ON book_work.fk_workOfWriters=workOfWriters.pk_workOfWriters
where book.fk_Language<>workOfWriters.fk_Language
--------------------------------------------------------------------------------------
SELECT COUNT(workOfWriters.pk_workOfWriters) as lox, language.titleLanguage FROM
((language INNER JOIN workOfWriters ON language.pk_language=workOfWriters.fk_language)
INNER JOIN work_writer ON workOfWriters.pk_workOfWriters=work_writer.fk_workOfWriters)
INNER JOIN Writer ON writer.pk_Writer=work_writer.fk_Writer
where work_writer.fk_Writer=(SELECT work_writer.fk_workOfWriters FROM work_writer
GROUP BY work_writer.fk_workOfWriters
ORDER BY count(*)
LIMIT 1)
GROUP BY language.titleLanguage
--------------------------------------------------------------------------------------
SELECT issued_fine.fk_issued, issued_fine.amountOfFine FROM issued_fine
where issued_fine.amountOfFine>=(SELECT AVG(issued_fine.amountOfFine) FROM issued_fine)
--------------------------------------------------------------------------------------
SELECT reader.firstname, reader.middlename, reader.lastname, sum(issued_fine.amountOfFine) FROM
(reader INNER JOIN issued
ON reader.pk_reader=issued.fk_reader) INNER JOIN issued_fine on issued.pk_issued=issued_fine.fk_issued
WHERE reader.pk_reader=
        (SELECT issued.fk_reader FROM
        issued INNER JOIN issued_fine
        ON issued.pk_issued=issued_fine.fk_issued
        GROUP BY issued.fk_reader
        ORDER BY SUM(issued_fine.amountOfFine) DESC
        LIMIT 1)
GROUP BY reader.firstname
--------------------------------------------------------------------------------------