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Determining How an Entity Should Be Stored › Location Modes for Entities in the Commonweather Database

Location Modes for Entities in the Commonweather Database

By following the guidelines presented in this chapter, you can assign appropriate location modes to the entities in your database. The table below shows how the location mode was decided upon for each entity in the Commonweather database.

Is this entity...

Both parent and child?

With optimal clustering?

Parent and not child

Child and not parent (w/optimal clustering)?

Generic retrieval and relatively static?

DEPARTMENT

N

-

Y

-

-

OFFICE

N

-

Y

-

-

PROJECT

Y

N

-

-

-

INS CO

N

-

Y

-

-

LIFE INS PLAN

N

-

N

N

Y

HEALTH INS

Y

N

-

-

-

PLAN

Y

N

-

-

-

NON-HOSPITAL

N

-

N

N

-

CLAIM

Y

N

-

-

-

DENTAL CLAIM

N

-

Y

-

-

HOSPITAL

Y

N

-

-

-

PHYSICIAN

N

-

Y

-

-

DENTIST

N

-

Y

-

-

EMPLOYEE

N

-

Y

-

-

JOB

 

 

 

 

 

SKILL

 

 

 

 

 

PATIENT

 

 

 

 

 

Location mode: Store CALC on primary key. For example, store the EMPLOYEE entity CALC on EMP ID.

Is this entity...

Both parent and child?

With optimal clustering?

Parent and not child

Child and not parent (w/optimal clustering)?

Generic retrieval and relatively static?

EMPOSITION

N

-

Y

-

-

EXPERTISE

N

-

Y

-

-

STRUCTURE

Y

N

-

-

-

WORKER

N

-

Y

-

-

PHONE

N

-

N

N

Y

SALARY

Y

N

-

-

-

GRADE

Y

N

-

-

-

COVERAGE

N

-

N

N

-

NON-HOSPITAL

Y

N

-

-

-

PROCEDURE

N

-

Y

-

-

DENTAL

Y

N

-

-

-

PROCEDURE

N

-

Y

-

-

Location mode: Store clustered on the optimal relationship. For example, store the EXPERTISE entity clustered on the EMP-EXPERTISE relationship