AS
Aliases (AS) надає таблиці чи колонці записів даних більш зрозуміле ім'я
SELECT CustomerID AS ID, CustomerName AS Customer
FROM Customers; // CustomerID, CustomerName ID, Customer
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SELECT CustomerName AS Customer, ContactName AS [Contact Person]
FROM Customers; // [] - дозволяють пробіл в назві
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SELECT CustomerName, Address + ', ' + PostalCode + ' ' + City + ', ' + Country AS Address
FROM Customers; // CustomerName, Address
SELECT CustomerName, CONCAT(Address,', ',PostalCode,', ',City,', ',Country) AS Address
FROM Customers;
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SELECT o.OrderID, o.OrderDate, c.CustomerName
FROM Customers AS c, Orders AS o
WHERE c.CustomerName='Around the Horn' AND c.CustomerID=o.CustomerID;
SELECT Orders.OrderID, Orders.OrderDate, Customers.CustomerName
FROM Customers, Orders
WHERE Customers.CustomerName='Around the Horn' AND Customers.CustomerID=Orders.CustomerID;
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Self JOIN
SELECT A.CustomerName AS CustomerName1, B.CustomerName AS CustomerName2, A.City
FROM Customers A, Customers B
WHERE A.CustomerID <> B.CustomerID
AND A.City = B.City
ORDER BY A.City;
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