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SELECT * 
FROM Products
WHERE UnitPrice = (
  SELECT MAX(UnitPrice)
  FROM Products
)

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?@?ł́A???̗?͂ǂ??ł??傤???B

SELECT * 
FROM Products
WHERE UnitPrice >= ALL (
  SELECT UnitPrice
  FROM Products
)

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SELECT * 
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WHERE UnitPrice < (
  SELECT AVG(UnitPrice)
  FROM Products
)

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SELECT * 
FROM Products Prod1
WHERE Prod1.UnitPrice > ALL(
  SELECT UnitPrice
  FROM Products Prod2
  WHERE Prod1.ProductID <> Prod2.ProductID
)

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SELECT ProductID, ProductName, UnitPrice
FROM Products Prod1
WHERE 5 > (
  SELECT Count(*)
  FROM Products Prod2
  WHERE Prod1.UnitPrice < Prod2.UnitPrice
)
ORDER BY UnitPrice DESC

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SELECT ProductID, ProductName, UnitPrice
FROM Products
ORDER BY UnitPrice DESC

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SELECT TOP 5 ProductID, ProductName, UnitPrice
FROM Products Prod1
ORDER BY UnitPrice DESC

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UPDATE Products SET UnitPrice = 81
WHERE ProductID IN (18,59,51)

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