Question

我在Microsoft SQL Server 2012上创建了一个数据库，我有两个表“dbo.Products”和“dbo.Categories”。我正在尝试查询这两个表，以便为星型模式创建PRODUCT维度表。

Products {ProductID, ProductName, SupplierID, CategoryID, QuantityPerUnit, UnitPrice, UnitsInStock, UnitsOnOrder, ReorderLevel, Discontinued}
Categories {CategoryID, CategoryName, Description}

这两个表来自Northwind数据库

Product Dimension包含从Northwind产品/类别表中查询的product_key，productID，productName，categoryID，categoryName和categoryDescription。

我正在使用的SQL代码在这里：

/*Create Dimension Table */
CREATE TABLE [dbo].[PRODUCT] (
[product_key] [int] IDENTITY (1, 1) NOT NULL Primary Key,
[productID] [int] NULL ,
[productName] nvarchar(30) NULL ,
[categoryID] [int] NULL ,
[categoryName] nvarchar(30) NULL ,
[categoryDescription] nvarchar(30) NULL 
) 

/* Populate (insert) Dimension Table with a select statement that joins 
Product and Categories. */
INSERT INTO [dbo].[PRODUCT] (productID, productName, categoryID, categoryName, categoryDescription)
   SELECT 
      ProductID, ProductName, CategoryID, CategoryName, CategoryDescription
   FROM 
      Products 
   INNER JOIN 
      Categories ON Categories.CategoryID = Products.CategoryID;

Answer 1

试试这个

INSERT INTO [acs4904_a1].[dbo].[PRODUCT] 
(productID, productName, categoryID, categoryName, categoryDescription)

SELECT 
P.ProductID, 
P.ProductName, 
C.CategoryID, 
C.CategoryName, 
C.CategoryDescription
FROM [acs4904_a1].[dbo].Products P 
INNER JOIN [acs4904_a1].[dbo].Categories C ON P.CategoryID=C.CategoryID;

Answer 2

您必须确定共享列的范围。

INSERT INTO [PRODUCT] (productID, productName, categoryID, categoryName, categoryDescription)
SELECT ProductID, ProductName, Products.CategoryID, CategoryName, CategoryDescription
FROM Products 
INNER JOIN Categories ON Categories.CategoryID=Products.CategoryID;

SQL INSERT INTO FROM SELECT

2 个答案: