ERD - how to set total participation in ERD::ERD_Relationship

[momochan]

Hi
   I want to set total participation relationship between entity, but I cannot find it.

My ERD is          |Employee| -- <works for>-- |Department|

I want to set      |Employee| -- <<works for>> == ||Department||

How can I set the relationship   <<works for>>==||Department||


momochan.

[qwerty]

Try Diagram Properties/Connectors/top right: IDEF1X. No idea if that really helps.

q.

[momochan]

Thank for your advise, qwerty

I try it, but it's not display.

Has anyone know how to fix this issue?

I use EA v12.1 (1230).
I think, EA not implement this feature, total participation relationship between weak-entity,
it's mandatory feature!!

momochan

[qwerty]

You need to be aware, that EA is not an ERD tool, but a UML tool which also has partial support for ERD (in the form of IDEF1X). What you can do is to write shape scripts for connectors you don't find in the defaults.

q.

[momochan]

What will I do. Could you advise me?

momochan

[Glassboy]

What will I do. Could you advise me?

You'd need to create an enhanced ERD MDG with all of the features that you need.  ERD is an internal technology so you won't have a MDG to copy.  The other option is to log a feature request with Sparx to enhance their MDG.

[qwerty]

If you're just after one additional connector type you could first try writing a shape script for that. Define a stereotype an assign it a shape script. You will need to define this in your repository. Depending on the environment you are working in, a MDG is the ultimate way to go.

q.

[momochan]

Thank for your advise, qwerty.

I will try it.

momochan

[@li]

0..1 -> partial/optional - 1(cardinality)
0..*-> optional -m(cardinality)
1..1-> total/mandatory - 1(cardinality)
1..*-> mandatory - m (cardinality)
Use UML2.1 notation to see modality/cardinality values on the ERD.

@li

[Richard Freggi]

Hello

I am curious what would total participation look like in Crow's Feet (I.E.) notation?  Or what would a SQL DDL code for total participation look like?

If it's 1:1 as suggested in previous post, it's certainly possible to do with EA but 1:1 is usually a sign of a problem in the data model... probably semantic mistakes or treating an attribute as if it was an entity, or using 2 entities where 1 would be enough.  I'm curious to know... thanks!

[Paolo F Cantoni]

Hello

I am curious what would total participation look like in Crow's Feet (I.E.) notation?  Or what would a SQL DDL code for total participation look like?

If it's 1:1 as suggested in previous post, it's certainly possible to do with EA but 1:1 is usually a sign of a problem in the data model... probably semantic mistakes or treating an attribute as if it was an entity, or using 2 entities where 1 would be enough.  I'm curious to know... thanks!

In our modelling environment, we've gone for crow's feet notation for ALL our Association related (or based) relationships.  We believe it best renders the relationship between the instances of the classifiers.  We even developed a mechanism for highlighting unconventional relationships (in Sharia law countries, a man may have 0..4 wives).

As far as 1:1  relationships, they need to be confirmed but aren't, prima facie, wrong.  Incorrect 1:1 associations are a common newbie, mistake, but we are usually cured of that pretty quickly.

Paolo

[Edit: corrected 1..1 to 1:1

[Glassboy]

As far as 1..1 (1) relationships, they need to be confirmed but aren't, prima facie, wrong.  Incorrect 1..1 associations are a common newbie, mistake, but we are usually cured of that pretty quickly.

I try to tell my wife that, but will she listen?

[Paolo F Cantoni]

As far as 1..1 (1) relationships, they need to be confirmed but aren't, prima facie, wrong.  Incorrect 1..1 associations are a common newbie, mistake, but we are usually cured of that pretty quickly.

I try to tell my wife that, but will she listen?

My bad I think I meant 1:1 relationships...    1..1 is the directional multiplicity.  No wonder your wife is confused...     [1..1:1..1] => [1:1]

[jamesjohn70]

Try Diagram Properties/Connectors/top right: IDEF1X. No idea if that really helps.