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HomeDatabaseMysql TutorialSqlServer示例数据库Northwind(一)实体关系

在学习Spss统计分析、EA画 实体 关系 图、PowerDesigner画 数据库 模型图等时,苦于找不到一个好的实例。由于实际工作中项目使用的表结构属于公司的商业保密内容,且在和大家交流时,其结构大家也不熟悉;而使用简单创建的Teacher、Student、Class等数据模型

在学习Spss统计分析、EA画实体关系图、PowerDesigner画数据库模型图等时,苦于找不到一个好的实例。由于实际工作中项目使用的表结构属于公司的商业保密内容,且在和大家交流时,其结构大家也不熟悉;而使用简单创建的Teacher、Student、Class等数据模型时,建表、录数据也是一个麻烦事;使用SqlServer的示例数据库正好,大伙都熟悉,又是现成的。

很多书籍、教程都使用Northwind数据库作为模型,但我一直对它不甚了解,今天特意下载后了解了一下,现在简单的记录下笔记,以后依次进行Spss等的学习。

实体关系(E-R)说明:

该实例的模型包含企业员工(Employee)、客户(Custom)、产品(Product)和订单(Order)四部分,大致为客户向企业员工订购产品。

(1)员工Employee:

包括Region(东西南北四个地区)和Territory(区域、城市)以及Employee(员工),Territory属于Region,但是Employee和Territory的关系式关联而非属于,即为某个员工可以关联多个区域,好比张三即在财务部又在行政部一样。

1 Eastern
2 Western
3 Northern
4 Southern

SqlServer示例数据库Northwind(一)实体关系

(2)客户Custom

SqlServer示例数据库Northwind(一)实体关系

(3)产品Product

产品进行了分类,所有有Category,此外同一名称的产品,可能存在多个供应商Supplier,不同供应商有不同的单价等信息。

SqlServer示例数据库Northwind(一)实体关系

(4)订单Order

一个订单下有多个产品,然后使用某一家物流进行配货。

SqlServer示例数据库Northwind(一)实体关系

对应于该实体关系数据库的设计,结构为:

其中员工表中有个自身关联,ReportTo为员工的直接领导,关联EmployeeID字段(领导也是公司员工嘛)。

SqlServer示例数据库Northwind(一)实体关系

理清了数据结构,然后就可以对其进行分析等处理了。

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