Boyce Codd Model

Seite 1

Boyce Codd Normal Form - known as BCNF

Every FD begins at a key

Table with sn + SSN

SSN + CN + DATE

SN + CN + DATE

**see pictures in phone**

Building the table:

E# | Ename | Class | Dept | Skills (since E# links to all these)

Dept | Mgr

Mgr | site | Job

Status + Skills | Salary

Class + Dept | Status

Draw Picture

Build tables

Do

SELECT DISTINCT E#, ename, class, Dept, Skills

FROM Empl

INTO newEmployees

4. Do a five way join to keep the original Empl table (in the pictures)

Entity Relationship Modeling

Entity - any person, place, thing, event, thought, concept , etc. Either real or imagined, about which persistent data must be kept for an enterprise

Entities have attributes, and all entities are BCNF

Entities are singular

Drawn as rounded corner rectangles

Entities have attributes with datatypes

# = primary key, dot = not null, clear dot = null allowed