Question

过去几天我一直在努力解决这个问题，而我所做的一切似乎都不起作用。任何帮助将非常感谢。这是一个家庭作业的问题，但我现在已经绞尽脑汁待了3天，我的教授一直都是ZERO的帮助。

我的困境是我正在尝试使用Columns创建一个全新的表，以及来自两个现有表的行。

问题如下：

使用AP数据库，创建一个名为“Invoices2Qtr2012”的新表，用于捕获供应商和   2012年第二季度的发票数据，用于发票和发票中的以下属性   供应商表：VendorName，InvoiceNumber，InvoiceTotal，InvoiceDueDate，PaymentDate。

此外，添加一个新列，显示每个发票付款是按时还是晚，以及   另一个新列，显示哪个供应商每个月的发票最多。这个   应该只包括2012年第二季度的数据。

以下是表格的结构：

发票：

InvoiceId
VendorID
InvoiceNumber
InvoiceDate
InvoiceTotal
PaymentTotal
CreditTotal
TermsID
InvoiceDue
PaymentDate

供应商：

VendorID
VendorName
VendorAddress1
VendorAddress2
VendorCity
VendorState
VendorZipCode
VendorPhone
VendorContactLName
VendorContactFName
DefaultTermsID
DefaultAccountNo

以下是我目前为止的代码：

CREATE TABLE Invoices2Qtr2012 AS
SELECT VendorName, InvoiceNumber, InvoiceTotal, InvoiceDueDate, PaymentDate
FROM Invoices, Vendors
WHERE InvoiceDate BETWEEN '2012-03-31' AND '2012-07-01'

Answer 1

我确信它可以减少到更少的陈述，它可能无法100％工作，但也许这可以让你开始或至少给你一些想法：

CREATE TABLE Invoices2Qtr2012 AS
SELECT VendorName, InvoiceNumber, InvoiceTotal, InvoiceDueDate, PaymentDate, InvoiceDate
FROM Invoices, Vendors
WHERE InvoiceDate BETWEEN '2012-03-31' AND '2012-07-01'

ALTER TABLE Invoices2Qtr2012
ADD LateOnTime varchar(255) DEFAULT 'On time'
ADD LargestInvoicePerMonth varchar(255) DEFAULT 'Not Largest'

UPDATE Invoices2Qtr2012
SET LateOnTime = 'Late'
WHERE PaymentDate > InvoiceDueDate;

UPDATE Invoices2Qtr2012
SET LargestInvoicePerMonth = 'Largest for April'
WHERE InvoiceTotal >= ALL (SELECT InvoiceTotal FROM Invoices2Qtr2012 WHERE InvoiceDate BETWEEN '2012-03-31' AND '2012-05-01')

UPDATE Invoices2Qtr2012
SET LargestInvoicePerMonth = 'Largest for May'
WHERE InvoiceTotal >= ALL (SELECT InvoiceTotal FROM Invoices2Qtr2012 WHERE InvoiceDate BETWEEN '2012-04-31' AND '2012-06-01')

UPDATE Invoices2Qtr2012
SET LargestInvoicePerMonth = 'Largest for June'
WHERE InvoiceTotal >= ALL (SELECT InvoiceTotal FROM Invoices2Qtr2012 WHERE InvoiceDate BETWEEN '2012-05-31' AND '2012-07-01')

Answer 2

SELECT INTO语句将为您创建表。所以你的代码将是：

SELECT INTO Invoices2Qtr2012  VendorName, InvoiceNumber, InvoiceTotal, InvoiceDueDate, PaymentDate
FROM Invoices, Vendors
WHERE InvoiceDate BETWEEN '2012-03-31' AND '2012-07-01'

在此之后，我建议创建适当的索引，键和约束。

表Invoices2Qtr2012必须不存在。

使用两个现有表中的数据创建新表

2 个答案: