Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > comp.databases.filemaker > #1460 > unrolled thread

relationship diagram

Back to article view | Back to comp.databases.filemaker

Contents

  relationship diagram JayBee <Jennifer_Beecroft@hotmail.com> - 2013-10-19 15:29 -0700
    Re: relationship diagram Martin Τrautmann <t-usenet@gmx.net> - 2013-10-20 04:34 +0000
    Re: relationship diagram "E. Appeldoorn" <ursus.kirk@ziggo.nl> - 2013-10-20 12:19 +0200
      Re: relationship diagram Helpful Harry <HelpfulHarry@BusyWorking.com> - 2013-10-21 09:11 +1300
        Re: relationship diagram "E. Appeldoorn" <ursus.kirk@ziggo.nl> - 2013-10-21 10:54 +0200

#1460 — relationship diagram

Hello
I'm using FMProAdvanced11 version 3.

I was reading an article on designing a relational databases recently and normalisation.  I think it described normalising a database to 3rd normal form.  It said that you must not have any many to many to many relationships and you must correct this by adding a new entity in between the many to many relationship.  
When I checked the relationship diagram for my company's database in FMPro11 there seemed to be quite a lot of many to many relationships in there .  


How bad is this?  Our database works as we need it to.


Does anybody know what this actually means in practice?

Many Thanks

[toc] | [next] | [standalone]

#1461

On Sat, 19 Oct 2013 15:29:49 -0700 (PDT), JayBee wrote:
>  When I checked the relationship diagram for my company's database in FMPro11 there seemed to be quite a lot of many to many relationships in there .  
> 
> 
>  How bad is this?  Our database works as we need it to.

That's the difference between theory and practice.

Just stick to your many-to-may relations. They work just fine and I do
not see any profit, adding an extra relationship table.

- Martin

[toc] | [prev] | [next] | [standalone]

#1462

JayBee schreef op 20-10-2013 00:29:
> Hello
> I'm using FMProAdvanced11 version 3.
>
> I was reading an article on designing a relational databases recently and normalisation.  I think it described normalising a database to 3rd normal form.  It said that you must not have any many to many to many relationships and you must correct this by adding a new entity in between the many to many relationship.
> When I checked the relationship diagram for my company's database in FMPro11 there seemed to be quite a lot of many to many relationships in there .
>
>
> How bad is this?  Our database works as we need it to.
>
>
> Does anybody know what this actually means in practice?
>
> Many Thanks
>
Jenny,

Although I understand what they are trying to do, you shouldn't be 
overly concerned about what others are saying. If your current set up 
works and you understand why it works then by all means keep it that 
way. In all my databases I have only one that got so cluttered that I 
had to rebuild (and use multiple occurances for the same table), but all 
the others have simple many-2-many relationships. (also referred to as a 
spider-graph)

-- 
met vriendelijke groeten,
Erik Appeldoorn

[toc] | [prev] | [next] | [standalone]

#1465

In article <ca10e$5263ae19$b254464b$3192@cache90.multikabel.net>, E.
Appeldoorn <ursus.kirk@ziggo.nl> wrote:
> JayBee schreef op 20-10-2013 00:29:
> > Hello
> > I'm using FMProAdvanced11 version 3.
> >
> > I was reading an article on designing a relational databases recently and
> > normalisation.  I think it described normalising a database to 3rd normal
> > form.  It said that you must not have any many to many to many
> > relationships and you must correct this by adding a new entity in between
> > the many to many relationship.
> > When I checked the relationship diagram for my company's database in
> > FMPro11 there seemed to be quite a lot of many to many relationships in
> > there .
> >
> >
> > How bad is this?  Our database works as we need it to.
> >
> >
> > Does anybody know what this actually means in practice?
> >
> > Many Thanks
> 
> Jenny,
> 
> Although I understand what they are trying to do, you shouldn't be 
> overly concerned about what others are saying. If your current set up 
> works and you understand why it works then by all means keep it that 
> way. In all my databases I have only one that got so cluttered that I 
> had to rebuild (and use multiple occurances for the same table), but all 
> the others have simple many-2-many relationships. (also referred to as a 
> spider-graph)

I haven't used the newer versions of FileMaker with the (rather silly)
relationship diagram, but as far as I understand it that diagram simply
shows the relationship links - it doesn't, and can't, tell you whether
they are one-to-one, one-to-many, many-to-one, or many-to-many. That
type of relationship information can only be known by what data and
records each table has.

[toc] | [prev] | [next] | [standalone]

#1468

Helpful Harry schreef op 20-10-2013 22:11:
> In article <ca10e$5263ae19$b254464b$3192@cache90.multikabel.net>, E.
> Appeldoorn <ursus.kirk@ziggo.nl> wrote:
>> JayBee schreef op 20-10-2013 00:29:
>>> Hello
>>> I'm using FMProAdvanced11 version 3.
>>>
>>> I was reading an article on designing a relational databases recently and
>>> normalisation.  I think it described normalising a database to 3rd normal
>>> form.  It said that you must not have any many to many to many
>>> relationships and you must correct this by adding a new entity in between
>>> the many to many relationship.
>>> When I checked the relationship diagram for my company's database in
>>> FMPro11 there seemed to be quite a lot of many to many relationships in
>>> there .
>>>
>>>
>>> How bad is this?  Our database works as we need it to.
>>>
>>>
>>> Does anybody know what this actually means in practice?
>>>
>>> Many Thanks
>>
>> Jenny,
>>
>> Although I understand what they are trying to do, you shouldn't be
>> overly concerned about what others are saying. If your current set up
>> works and you understand why it works then by all means keep it that
>> way. In all my databases I have only one that got so cluttered that I
>> had to rebuild (and use multiple occurances for the same table), but all
>> the others have simple many-2-many relationships. (also referred to as a
>> spider-graph)
>
> I haven't used the newer versions of FileMaker with the (rather silly)
> relationship diagram, but as far as I understand it that diagram simply
> shows the relationship links - it doesn't, and can't, tell you whether
> they are one-to-one, one-to-many, many-to-one, or many-to-many. That
> type of relationship information can only be known by what data and
> records each table has.
>

The graph together with the fields it joins, does give a hint, but no 
answer, the questions of normalisation and simplification are quit often 
confused. Both serve a different purpose. normalisation is the need to 
have all solutions looking and and acting the same (My simplified way to 
explain this). Preferrably across platform and software. IMHO usefull if 
you are a pro, on several platforms or when trying to solve complicated 
setups. Simplification within filemaker is the need to clean up the 
spider-graph. So called because it has a body (a table) with many many 
legs (relationships). In the end confusing the developer. When creating 
complex solutions I use a mix of solutions to suit my needs. Mostly a 
combo of the spider and the anchor-buoy.

my explanation is probably flawed, but there it is.

-- 
met vriendelijke groeten,
Erik Appeldoorn

[toc] | [prev] | [standalone]

Back to top | Article view | comp.databases.filemaker

csiph-web