relationships

skellie

Am comfortable with database design but understand that I should really think in terms of relationships. Struggling a little with this concept.

Here is an example. The web app asks the question, " do you participate in any high risk sports? Response is yes / no.
If yes then the app presents a selection of high risk sports such as scuba, mountaineering and back country skiing (tick boxes). For each sport chosen there are questions specific to that sport.

How many objects in this scenario and what are they?
Thanks

kklosson

It's possible to do this by creating an object called something like HighRiskSports. There can be a dropdown for a selection of sports including ability to enter your own value. This requires the user to recursively add each item if there are more than one.

Alternatively, you can have an attribute (instead of object) that allows for one or more selection of items. I don't know if you can include a free input this ay (me thinks not). I haven't done this but I quite sure it's doable. The former strategy would be my preference if you think it's okay to the user.

skellie

I think my lack of understanding in more basic. Say for example a person can have only one address, one home. In this case it can make sense to locate all personal data in one table, ie name, street, city, state, ph etc goes into one table. But if a person can have two addresses then in a database situation I might create a separate table for address and relate them one to many. So a broad rule of thumb in a database is create a new table for one-to-many situations. Is it the same with AwareIm. I know that AwareIm encourages us not think in database terms but I feel I do not have a good handle on the "business object" way of doing things.

So in my example above, the insurance client completes a questionnaire asking about many medical and non-medical issues. One of the questions is about high risk sports, and he can give a yes /no response. I might call this business object "insuranceQuestionnaire". Then if he answers yes, he gets a pick list or check box selection of different high risk sports. He cannot add to this, it is a fixed list. But there are many different sports in this pick list and he must be able to choose multiple sports. So here is one-to-many situation - one yes can have many sports. So thinking in database terms is this a new business object? If yes then might call this doesHighRiskSport. And then for each sport selected he is presented with more questions specific to that sport. Then I suppose scuba would get its own object, mountaineering its own and so-on. In a db would likely also create new tables for each of the sports in the pick list and relate them to doesHighRiskSport one-to-one. A further complication in scuba, for example, is that I would ask what type of diving he does. The possible responses would be open water, cave, wreck, rescue etc. And each one of them might have a few questions unique to the risk. And so the one-to-many scenario can get quite hectic.

Guess what I am asking is whether a database approach can work - if a db requires a new table then likewise does AwareIm also require a new object?

customaware

Hi Skellie

This is entirely doable in Aware.

I can do a demo for you but am a bit tied up at the moment. However, have a crack yourself first...... Here is my thinking.

BO: HighRiskSport
SportCode Text 5
SportName Text 40
Questions SportQuestion Multiple Allowed OwnedBy (HighRiskSport) Call matching Attribute in SportQuestion ... Sport

BO: SportQuestion
QuestionNumber Number (allow admin to change order)
Question Text 200
Sport HighRiskSport (will be created automatically when you create Questions in HighRiskSport)

Now in your Person BO or RegularUser BO

BO Person (Or RegularUser)
Name
Address
Blah, blah blah
Sports data type = HighRiskSports or type Peer and Multiple Allowed
SportAnswers PersonSportAnswers Multiple Allowed, OwnedBy Person. Matching Attribute is Person.

You can now set this Attribute on the Person for to be a Swap Select.

You do not need a Yes,No attribute to say if the person engages in High Risk Sports. That will be always true if the person selects any of the Sports - as we only have High Risk Sports.

Ok.... That is the first part.....

The complicated part comes from deciding how to deal with the questions for each sport if the user has selected it.

I would create a new BO called PersonSportAnswers.....something like....

Question SportQuestion
sc_Question ShortCut SportQuestion.Question
sc_SportCode ShortCut SportQuestion.Sport.SportCode
Answer text 200
Person Person

So..... what happens is that when the person selects their sports..... you call a process that creates a PersonSportAnswer for each SportQuestion or each HighRiskSport that the person has selected.

BO parameter for the Process is Person

FIND SportQuestion WHERE (SportQuestion.Sport IN Person.Sports)
CREATE PersonSportAnswers WITH PersonSportAnswers.Person=Person, PersonSportAnswers.Question=SportQuestion

Things to consider here are...

First time they select... no problem... just create

FIND SportQuestion WHERE (SportQuestion.Sport IN Person.Sports)
CREATE PersonSportAnswers WITH PersonSportAnswers.Person=Person, PersonSportAnswers.Question=SportQuestion

If modified later.... you need to delete the PersonSportAnswers for the persons HighRiskSports that are no longer selected AND
you need to create PersonSportAnswers for HighRiskSport that are now selected but were not selected before.

FIND PersonSportAnswers WHERE NOT(PersonSportAnswers.Sport IN Person.Sports)
DELETE PersonSportAnswers

FIND SportQuestion WHERE (SportQuestion.Sport IN Person.Sports AND NOT (SportQuestion IN PersonSportAnswers)
CREATE PersonSportAnswers WITH PersonSportAnswers.Person=Person, PersonSportAnswers.Question=SportQuestion

Then you need to work out how you want to progress through the answering of each question. Maybe a Navigation structure to the form or selecting each sport one at a time and then progressing through the answers for that Sport.

There are a range of ways to tackle this and really this is just some broad thinking off the top of my head. I am sure if I coded it up then it would most likely change but it could be a start for you. Generally, once you start then the thinking will become clearer as you see the results and what does and does not suit.

Clear as mud eh? 😉

skellie

Thanks Mark, lots of good info here. I will start putting it together and see how it goes. Away this weekend, will start Monday.

I read one of Vladimir's blogs yesterday re business objects and was starting to think that I was really on the wrong track. He says look at business objects as nouns. So if this is the case then the following might be objects for a life insurance app: client details, insurance questionnaire, medical examination, financial report, etc. But if this is the case then the insurance questionnaire alone would comprise hundreds of attributes (all the base medical and non-medical questions plus all the drill-down reflex questions). This is what throws me still. Is it possible for the complete insurance questionnaire to be one business object? Would not do this in a database setup.

Thanks for taking the time Mark, appreciate it ...

skellie

I'm a little slow today, did not pick up the on the 'eh'.
A Canadian in Mongolia? Looked up pics of Ulaanbaatar, good looking country...

kklosson

My app requires the user to complete an extensive personal history questionnaire. The questionnaire itself is an object with over 200 attributes but there are also many child related object. For example, a list of personal references, a list of previous residences, etc. AwareIM is very suitable to this requirement.

customaware

Aussie in Mongolia. 😉

skellie

Back again mate, making slow progress.
It's these darn objects that are throwing me. Will try to figure it out more... . Cheers