Sparx Systems Forum

Enterprise Architect => General Board => Topic started by: JimF on March 30, 2005, 11:53:21 am

Title: What is an ERLink?
Post by: JimF on March 30, 2005, 11:53:21 am

I searched help and the forum but found nothing. :-/

Title: Re: What is an ERLink?
Post by: KP on March 30, 2005, 03:11:31 pm

I believe it's been superceded now, but it used to be the foreign key association between two table elements. Why do you ask? Questions like that make me nervous!  :-/

Title: Re: What is an ERLink?
Post by: JimF on March 30, 2005, 03:26:57 pm

Because I think the arrow at the end of the association I think will confuse my users, for whom an arrow always means "something flows to something". The multiplicity label is there, that's nice, but I wanted to get rid of the arrow, maybe put crow's feet, but at least get rid of the arrow. I changed the connection type to ERLink (I figured ER maybe stood for Entity-Relation) and I didn't get crows' feet but I did get rid of the arrow. Then I decided to check it out, but couldn't find it in the help or even on the forums everywhere. Shouldn't everything be documented somewhere? I have found in my brief experience with EA that there seems to be a lot of little things like this that aren't documented, or at least not well.


Tell you what, though, once I changed the connection types and also got rid of the PK and FK name labels on the connections, leaving just the field= field and multiplicity, I had a pretty nice little set of ERD diagrams. :) And it's easy to copy to Word.

Title: Re: What is an ERLink?
Post by: KP on March 30, 2005, 04:44:16 pm

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I changed the connection type to ERLink

Hmmm, I was right to be nervous, it probably shouldn't be in that list. :-/

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Shouldn't everything be documented somewhere?

It's a deprecated feature, still there to support legacy models, so it has been removed from the documentation. For new models, associations give you every the ERLink used to.

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I think the arrow at the end of the association I think will confuse my users, for whom an arrow always means "something flows to something".

Two additional choices for you: 1. Tell your users the foreign key "points to" the primary key, hence the arrowhead. 2. Right click the association and set Direction to Unspecified.

Hope this helps

Title: Re: What is an ERLink?
Post by: JimF on March 30, 2005, 06:18:03 pm

OK, guess I'll go with option #2, thanks.

I think EA works real well for me as a ER diagrammer. As for the rest of the UML, I'm reading books but not quite "getting it". I shall keep trying.