使用两个现有表中的数据创建新表

Question

过去几天我一直在为此苦苦挣扎，但我所做的一切似乎都不起作用。任何帮助将不胜感激。这是一道家庭作业题，但我已经绞尽脑汁 3 天了，我的教授得到了零帮助。

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

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 年第二季度发票中以下属性的发票数据和 供应商表：VendorName、InvoiceNumber、InvoiceTotal、InvoiceDueDate、PaymentDate。

此外，添加一个新列，显示每张发票付款是按时还是延迟，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。

这是表格的结构：

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

这是我目前的代码：

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语句，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。

表格 Invoices2Qtr2012 不得存在。