Answer:
1) SELECT author.name, author.email
FROM author, paper_author, paper
WHERE author.id = paper_author.id
AND paper_author.id = paper.id
AND UPPER(paper.title) = ('A novel approach of mining EHR data');
2) SELECTpaper_review.id, paper_review. decision, paper_review.comment
FROM paper_review, Paper
WHERE paper_review.id = paper.id
AND paper.title = 'comparing big-data systems';
3) SELECT Paper.title, COUNT(Paper_author.id)
FROM Paper, Paper_author
WHERE Paper.id = Paper_author.id
GROUP BY Paper.title;
4) SELECT Author.name
FROM Author
WHERE Author.id IN (SELECT Paper_author.id
FROM Paper_author
GROUP BY Paper_author.id
HAVING COUNT(Paper_author.id) >= 2);
5) SELECT DISTINCT a.name
FROM Author AS a
INNER JOIN paper_author AS pa
ON a.id=pa.id
WHERE EXISTS (
SELECT 1
FROM Author aa
INNER JOIN paper_author paa
ON aa.id=paa.id
WHERE name='Dr. Chen'
AND paa.id = pa.id
AND aa.id != a.id
);
Explanation:
The SQL statements return the queries from six different tables in the database
