SELECT Author, COUNT(*) as NumArticlesFROM MagazinesGROUP BY AuthorORDER BY NumArticles;SELECT Author, COUNT(*) as NumBooksFROM BooksGROUP BY AuthorORDER BY NumBooks;
SELECT Author, NumPublications, PubTypeFROM ( SELECT Author, COUNT(*) as NumPublications, 'Magazine' as PubType, 0 as SortIndex FROM Magazines GROUP BY Author UNION SELECT Author, COUNT(*) as NumPublications, 'Book' as PubType, 1 as SortIndex FROM Books GROUP BY Author)ORDER BY SortIndex, NumPublications;
CREATE TRIGGER IF NOT EXISTS RemoveAuthorAFTER DELETE ON BooksBEGIN DELETE FROM Authors WHERE Author NOT IN (SELECT Author FROM Books);END;
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