Graphical Notation - Data Warehouse Systems: Design and Implementation - page 588

Union Difference Join

Condition :
EmployeeID = EmployeeKey
Join Type: Left Outer Join

Input* : CityName,
StateKey, CountryKey
Output : CityName,
StateKey, CountryKey

Input* : CityName,
StateKey, CountryKey
Output : CityName,
StateKey, CountryKey
Keep Duplicates: No

Lookup Lookup Lookup Lookup

Retrieve : StateKey
Database: NorthwindDW
Query: State Join Country
Where : State, Country
Matches : StateName,
CountryName

Replace : StateKey
Database: NorthwindDW
Query: State Join Country
Where : State, Country
Matches : StateName,
CountryName

Retrieve : CountryKey
Database: NorthwindDW
Table: Country
Where : Country
Matches : CountryName

Replace : CountryKey
Database: NorthwindDW
Table: Country
Where : Country
Matches : CountryName

N-ary data tasks

Retrieve : CountryKey
Database: NorthwindDW
Table: Country
Where : Country
Matches : CountryName

Retrieve : CountryKey
Database: NorthwindDW
Table: Country
Where : Country
Matches : CountryName

Condition :
Found?

Y

Found

Lookup Lookup

N

NotFound

Shorthand notation for lookup