我想知道是否有人对如何规范化数据库有任何建议。现在,我不是要设计结构,而是要实际将数据库数据从旧结构移动到新的规范化结构。我知道我可以编写类似PHP脚本的内容,但是我想知道是否有一种方法可以在SQL中进行。特别是MySQL。
**编辑:有人尝试过SwisSQL吗?这是一个迁移工具,但我不确定它是否能满足我的要求。
这是在脚本中标准化表的示例。我建议你做这样的事情
e.g Table: tbl_tmpData Date, ProductName, ProductCode, ProductType, MarketDescription, Units, Value 2010-01-01, 'Arnotts Biscuits', '01', 'Biscuit', 'Store 1', 20, 20.00 2010-01-02, 'Arnotts Biscuits', '01', 'Biscuit', 'Store 2', 40, 40.00 2010-01-03, 'Arnotts Biscuits', '01', 'Biscuit', 'Store 3', 40, 40.00 2010-01-01, 'Cola', '02', 'Drink', 'Store 1', 40, 80.00 2010-01-02, 'Cola', '02', 'Drink', 'Store 2', 20, 40.00 2010-01-03, 'Cola', '02', 'Drink', 'Store 2', 60, 120.00 2010-01-01, 'Simiri Gum', '03', 'Gum', 'Store 1', 40, 80.00 2010-01-02, 'Simiri Gum', '03', 'Gum', 'Store 2', 20, 40.00 2010-01-03, 'Simiri Gum', '03', 'Gum', 'Store 3', 60, 120.00
您将首先创建日期表:
CREATE TABLE tbl_Date ( DateID int PRIMARY KEY IDENTITY(1,1) ,DateValue datetime ) INSERT INTO tbl_Date (DateValue) SELECT DISTINCT Date FROM tbl_Data WHERE Date NOT IN (SELECT DISTINCT DateValue FROM tbl_Date)
然后,您将创建您的市场表
CREATE TABLE tbl_Market ( MarketID int PRIMARY KEY IDENTITY(1,1) ,MarketName varchar(200) ) INSERT INTO tbl_Market (MarketName) SELECT DISTINCT MarketDescription FROM tbl_tmpData WHERE MarketName NOT IN (SELECT DISTINCT MarketDescription FROM tbl_Market)
然后,您将创建您的ProductType表
CREATE TABLE tbl_ProductType ( ProductTypeID int PRIMARY KEY IDENTITY(1,1) ,ProductType varchar(200) ) INSERT INTO tbl_ProductType (ProductType) SELECT DISTINCT ProductType FROM tbl_tmpData WHERE ProductType NOT IN (SELECT DISTINCT ProductType FROM tbl_ProductType)
然后,您将创建您的产品表
CREATE TABLE tbl_Product ( ProductID int PRIMARY KEY IDENTITY(1,1) , ProductCode varchar(100) , ProductDescription varchar(300) ,ProductType int ) INSERT INTO tbl_Product (ProductCode, ProductDescription, ProductType) SELECT DISTINCT tmp.ProductCode,tmp.ProductName, pt.ProductType FROM tbl_tmpData tmp INNER JOIN tbl_ProductType pt ON tmp.ProductType = pt.ProductType WHERE ProductCode NOT IN (SELECT DISTINCT ProductCode FROM tbl_Product)
然后,您将创建数据表
CREATE TABLE tbl_Data ( DataID int PRIMARY KEY IDENTITY(1,1) , DateID varchar(100) , ProductID varchar(100) , MarketID varchar(300) ,Units decimal(10,5) , value decimal(10,5) ) INSERT INTO tbl_Data (ProductID, MarketID, Units, Value) SELECT t.DateID , p.ProductID , m.MarketID , SUM(tmp.Units) , SUM(tmp.VALUE) FROM tbl_tmpData tmp INNER JOIN tbl_Date t ON tmp.Date = t.DateValue INNER JOIN tbl_Product p ON tmp.ProductCode = p.ProductCode INNER JOIN tbl_Market m ON tmp.MarketDescription = m.MarketName GROUP BY t.DateID, p.ProductID, m.MarketID ORDER BY t.DateID, p.ProductID, m.MarketID