选择正确的查询

Question

我必须构建一个将为客户创建 table 的查询 - 'Frank Spencer'（您将在下面的客户 table 中看到他）。

新 table 应该包含客户购买过的每件产品的总计，不包括尚未发货的订单，每个产品在新 [=37= 中只出现一次].

我的table如下。

你能告诉我下面哪一个是最好的吗？

a) with customer as (select * from customers where lower(CustomerName) = 'frank spencer'),customerorders as(select OrderId from orders o where o.CustomerId in(select CustomerId from customer) and OrderShipped = 'True') select sum(oi.QuantityOrdered) as TotalOrdered, s.ItemName into franksorders from orderitems oi join stock s on oi.StockItemId = s.StockItemId where OrderId in(select * from customerorders) group by ItemName order by ItemName

b) with customer as (select * from customers where lower(CustomerName) = 'frank spencer') join customerorders as(select OrderId from orders o where o.CustomerId in(select CustomerId from customer) and OrderShipped = 'True') select total(oi.QuantityOrdered) as TotalOrdered, s.ItemName into new table franksorders using orderitems oi join stock s on oi.StockItemId = s.StockItemId where OrderId in(select * from customerorders) group by ItemName order by ItemName

c) with customer (select * from customers where 'frank spencer' in (CustomerName)) with customerorders (select OrderId from orders o where o.CustomerId in(select CustomerId from customer) and OrderShipped = 'True') select sum(oi.QuantityOrdered) as TotalOrdered, s.ItemName create table franksorders using orderitems oi join stock s on oi.StockItemId = s.StockItemId where OrderId in(select * from customerorders) group by ItemName order by ItemName

d) using customer with (select * from customers where CustomerName = 'frank spencer' and customerorders with(select OrderId from orders o where o.CustomerId in(select CustomerId from customer) then OrderShipped = 'True') select sum(oi.QuantityOrdered) as TotalOrdered, s.ItemName into franksorders from orderitems oi join stock s on oi.StockItemId = s.StockItemId where OrderId in(select * from customerorders) group by ItemName order by ItemName

Answer 1

B、C 和 D 中有一个 USING，据我所知，SQL 服务器不支持它。使用是，但不是使用。所以答案是A。下次，您可以使用poorsql.com来格式化您的代码，这样更容易发现错误。

WITH customer
AS (
    SELECT *
    FROM customers
    WHERE lower(CustomerName) = 'frank spencer'
    )
    ,customerorders
AS (
    SELECT OrderId
    FROM orders o
    WHERE o.CustomerId IN (
            SELECT CustomerId
            FROM customer
            )
        AND OrderShipped = 'True'
    )
SELECT sum(oi.QuantityOrdered) AS TotalOrdered
    ,s.ItemName
INTO franksorders
FROM orderitems oi
INNER JOIN stock s ON oi.StockItemId = s.StockItemId
WHERE OrderId IN (
        SELECT *
        FROM customerorders
        )
GROUP BY ItemName
ORDER BY ItemName

选择正确的查询

Chosing the right query

sql

tsql

sql-server

subquery