Database Reference
In-Depth Information
A.2 Relational Model
name
Product
primary key
attribute
attributes
ProductKey
ProductNumber
ProductName
Description
alternate key
AK: ProductNumber
Relational table
(with attributes and keys shown)
Product
Category
primary key
attribute
primary key
attribute
ProductKey
ProductNumber
ProductName
Description
CategoryKey
CategoryKey
CategoryName
Description
foreign key
attribute
Referential integrity
attributes
name
primary key
attribute
Product
foreign key
attribute
Product
Key
Product
Number
Product
Name
Category
Key
Description
1
2
QB876
Milk
Soup
...
C1
instances
QD555
...
C2
Relational table with instances
A.3 MultiDim Model for Data Warehouses
name
Product
Level
(short description)
name
Product
ProductNumber
ProductName
Description
Size
identifier attribute
descriptive attributes
Level
(with attributes and identifiers shown)
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