Appendix,C,The,University,Lab:
Conceptual,Design,Verification,,Logical,Design,,and,Implementation
Appendix,C
The,University,Lab:,Conceptual,Design,,Verification,,Logi
cal,Design,,and,Implementation
Discussion,Focus
How,is,a,database,design,verified,,and,why,is,such,verification,necessary?
Use,our,detailed,answer,to,question,1,to,focus,class,discussion,on,database,design,verification.,Stress,
that,the,verification,process,uses,the,initial,ER,model,as,a,communication,tool.
The,designer,may,begin,the,verification,process,by,describing,the,organization's,operations,to,its,end,
users,,basing,the,detailed,description,on,the,initial,ER,model.,Next,,explain,how,the,operations,will,be,
supported,by,the,database,design.,Stress,that,the,design,must,support,the,end-
user,application,views,,outputs,,and,inputs.,Points,to,be,addressed,include,such,questions,as:
Is,the,description,accurate?,If,not,,what,aspects,of,the,description,must,be,corrected?
Does, the, model, support, the, end-user, requirements?, If, not,, what, aspects, of, the, end-
user,requirements,have,not,been,addressed,or,have,been,addressed,inadequately?
Keep, in, mind, that, even, a, model, that, perfectly, addresses, all, initially, determined, end, user, requiremen
ts,is,likely,to,need,adjustments,as,those,end,users,begin,to,understand,the,ramifications,of,the,databas
e,design's,capabilities.,In,many,cases,,the,end,users,may,learn,what,the,organization's,processes,and,p
rocedures,actually,are,,thus,leading,to,new,requirements,and,the,perception,of,new,opportunities.,Th
e,database,designer,must,keep,such,likely,developments,in,mind,,especially,if,(s)he,works,as,a,databas
e,design,consultant.,(Anticipation,of,such,developments,must,be,factored,into,the,contract,negotiation
s,for,consulting,fees.)
Discuss,the,role,of,the,system,modules.
1
, Appendix,C,The,University,Lab:
Conceptual,Design,Verification,,Logical,Design,,and,Implementation
The, use, of, system, modules, can, hardly, be, overemphasized, in, a, database, design, environment., Stre
ss,these,module,characteristics,and,features:
Modules,represent,subsets,of,the,database,model:,Smaller,"pieces",are,more,easily,unders
tood.
Modules,are,self-
contained,and,accomplish,a,specific,system,function;,if,such,a,system,function,must,be,
modified,,other,functions,remain,unaffected.
Modules,fit,into,a,modular,database,design,,which,is,more,easily,modified,and,adapted,to,
new,circumstances.,Because,modification,efforts,are,focused,on,a,database,subset,,produ
ctivity,of,both,designers,and,application,developers,is,likely,to,be,enhanced.
Module,interfaces,must,be,clear,if,the,modules,are,expected,to,work,well,within,the,overall,system.
2
, Appendix,C,The,University,Lab:
Conceptual,Design,Verification,,Logical,Design,,and,Implementation
Answers,to,Review,Questions
1. Why,must,a,conceptual,model,be,verified?,What,steps,are,involved,in,the,verification,process?
The,verification,of,a,conceptual,model,is,crucial,to,a,successful,database,design.,The,verification,pr
ocess,allows,the,designer,to,check,the,accuracy,of,the,database,design,by:
Re-examining,data,and,data,transformations.
Enabling,the,designer,to,evaluate,the,design,efficiency,relative,to,the,end,user's,and,
system's,design,goals.
Keep,in,mind,that,,to,a,large,extent,,the,best,design,is,the,one,that,serves,the, end-
user,requirements,best.,For,example,,a,design,that,works,well,for,a,manufacturing,firm,may,not,fit
,the,needs,of,a,marketing,research,firm,,and,vice,versa.
The,verification,process,helps,the,designer,to,avoid,implementation,problems,later,by:
Validating,the,model's,entities.,(Remember,the,minimal,data,rule.)
Confirming,entity,relationships,and,eliminating,duplicate,,unnecessary,,or,improperly,
defined,relationships.
Eliminating,data,redundancies.
Improving,the,model's,semantic,precision,to,better,represent,real-world,operations.
Confirming,that,all,user,requirements,(processing,,performance,,or,security),are,met.
Verification,is,a,continuous,activity,in,any,database,design.,The,database,design,process,is,evolutio
nary,in,nature:,It,requires,the,continuous,evaluation,of,the,developing,model,by,examining,the,eff
ect,of,adding,new,entities,and,by,confirming,that,any,design,changes,enhance,the,model's,accurac
y.
The,verification,process,requires,the,following,steps:
1. Identify,the,database's,central,entity.
The, central, entity, is, the, most, important, entity, in, our, database,, and, most, of, the, oth
er,entities,depend,on,it.
3
, Appendix,C,The,University,Lab:
Conceptual,Design,Verification,,Logical,Design,,and,Implementation
2. Identify,and,define,each,module,and,its,components.
The, designer, divides, the, database, model, into, smaller, sets, that, reflect, the, data, needs,
of,particular,systems,modules,such,as,inventory,,orders,,payroll,,etc.
3. Identify,and,define,each,of,the,module's,processes.
Specifically,, this, step, requires, the, identification, and, definition, of, the, database, transactions
that,represent,the,module's,real-world,operations.
4
Conceptual,Design,Verification,,Logical,Design,,and,Implementation
Appendix,C
The,University,Lab:,Conceptual,Design,,Verification,,Logi
cal,Design,,and,Implementation
Discussion,Focus
How,is,a,database,design,verified,,and,why,is,such,verification,necessary?
Use,our,detailed,answer,to,question,1,to,focus,class,discussion,on,database,design,verification.,Stress,
that,the,verification,process,uses,the,initial,ER,model,as,a,communication,tool.
The,designer,may,begin,the,verification,process,by,describing,the,organization's,operations,to,its,end,
users,,basing,the,detailed,description,on,the,initial,ER,model.,Next,,explain,how,the,operations,will,be,
supported,by,the,database,design.,Stress,that,the,design,must,support,the,end-
user,application,views,,outputs,,and,inputs.,Points,to,be,addressed,include,such,questions,as:
Is,the,description,accurate?,If,not,,what,aspects,of,the,description,must,be,corrected?
Does, the, model, support, the, end-user, requirements?, If, not,, what, aspects, of, the, end-
user,requirements,have,not,been,addressed,or,have,been,addressed,inadequately?
Keep, in, mind, that, even, a, model, that, perfectly, addresses, all, initially, determined, end, user, requiremen
ts,is,likely,to,need,adjustments,as,those,end,users,begin,to,understand,the,ramifications,of,the,databas
e,design's,capabilities.,In,many,cases,,the,end,users,may,learn,what,the,organization's,processes,and,p
rocedures,actually,are,,thus,leading,to,new,requirements,and,the,perception,of,new,opportunities.,Th
e,database,designer,must,keep,such,likely,developments,in,mind,,especially,if,(s)he,works,as,a,databas
e,design,consultant.,(Anticipation,of,such,developments,must,be,factored,into,the,contract,negotiation
s,for,consulting,fees.)
Discuss,the,role,of,the,system,modules.
1
, Appendix,C,The,University,Lab:
Conceptual,Design,Verification,,Logical,Design,,and,Implementation
The, use, of, system, modules, can, hardly, be, overemphasized, in, a, database, design, environment., Stre
ss,these,module,characteristics,and,features:
Modules,represent,subsets,of,the,database,model:,Smaller,"pieces",are,more,easily,unders
tood.
Modules,are,self-
contained,and,accomplish,a,specific,system,function;,if,such,a,system,function,must,be,
modified,,other,functions,remain,unaffected.
Modules,fit,into,a,modular,database,design,,which,is,more,easily,modified,and,adapted,to,
new,circumstances.,Because,modification,efforts,are,focused,on,a,database,subset,,produ
ctivity,of,both,designers,and,application,developers,is,likely,to,be,enhanced.
Module,interfaces,must,be,clear,if,the,modules,are,expected,to,work,well,within,the,overall,system.
2
, Appendix,C,The,University,Lab:
Conceptual,Design,Verification,,Logical,Design,,and,Implementation
Answers,to,Review,Questions
1. Why,must,a,conceptual,model,be,verified?,What,steps,are,involved,in,the,verification,process?
The,verification,of,a,conceptual,model,is,crucial,to,a,successful,database,design.,The,verification,pr
ocess,allows,the,designer,to,check,the,accuracy,of,the,database,design,by:
Re-examining,data,and,data,transformations.
Enabling,the,designer,to,evaluate,the,design,efficiency,relative,to,the,end,user's,and,
system's,design,goals.
Keep,in,mind,that,,to,a,large,extent,,the,best,design,is,the,one,that,serves,the, end-
user,requirements,best.,For,example,,a,design,that,works,well,for,a,manufacturing,firm,may,not,fit
,the,needs,of,a,marketing,research,firm,,and,vice,versa.
The,verification,process,helps,the,designer,to,avoid,implementation,problems,later,by:
Validating,the,model's,entities.,(Remember,the,minimal,data,rule.)
Confirming,entity,relationships,and,eliminating,duplicate,,unnecessary,,or,improperly,
defined,relationships.
Eliminating,data,redundancies.
Improving,the,model's,semantic,precision,to,better,represent,real-world,operations.
Confirming,that,all,user,requirements,(processing,,performance,,or,security),are,met.
Verification,is,a,continuous,activity,in,any,database,design.,The,database,design,process,is,evolutio
nary,in,nature:,It,requires,the,continuous,evaluation,of,the,developing,model,by,examining,the,eff
ect,of,adding,new,entities,and,by,confirming,that,any,design,changes,enhance,the,model's,accurac
y.
The,verification,process,requires,the,following,steps:
1. Identify,the,database's,central,entity.
The, central, entity, is, the, most, important, entity, in, our, database,, and, most, of, the, oth
er,entities,depend,on,it.
3
, Appendix,C,The,University,Lab:
Conceptual,Design,Verification,,Logical,Design,,and,Implementation
2. Identify,and,define,each,module,and,its,components.
The, designer, divides, the, database, model, into, smaller, sets, that, reflect, the, data, needs,
of,particular,systems,modules,such,as,inventory,,orders,,payroll,,etc.
3. Identify,and,define,each,of,the,module's,processes.
Specifically,, this, step, requires, the, identification, and, definition, of, the, database, transactions
that,represent,the,module's,real-world,operations.
4
