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SELECT first.cname, second.cname, first.rating
FROM Customers first, Customers second
WHERE first.rating = second.rating;
Pereira | Hoffman | |
Clemens | Hoffman | |
Hoffman | Hoffman | |
Liu | Giovanni | |
Giovanni | Giovanni | |
Liu | Liu | |
Giovanni | Liu | |
Cisneros | Grass | |
Grass | Grass | |
Pereira | Clemens | |
Clemens | Clemens | |
Hoffman | Clemens | |
Cisneros | Cisneros | |
Grass | Cisneros | |
Pereira | Pereira | |
Clemens | Pereira | |
Hoffman | Pereira |
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SELECT first.cname, second.cname, first.rating
FROM Customers first, Customers second
WHERE first.rating = second.rating
AND first.cname < second.cname;
2.
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Clemens | Hoffman | |
Giovanni | Liu | |
Cisneros | Grass | |
Clemens | Pereira | |
Hoffman | Pereira |
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SELECT first.onum,ftirst.cnum, first.snum, second.onum, second.cnum,second.snum
FROM Orders first, Orders second
WHERE first.cnum = second.cnum
AND first.snum <> second.snum;
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