USE Northwind
GO
SELECT
OrderID,
YEAR(orderdate) AS orderyear
FROM dbo.Orders
WHERE orderyear > 2006 ;
以上述語法為例,欄位別名(orderyear) 屬於邏輯查詢欄位,尚未被定義。因此無法在where子句中使用。SQL Server的邏輯查詢處理依序如下:
(1) FROM
(2) WHERE
(3) GROUP BY
(4) HAVING
(5) SELECT
(6) ORDER BY
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