The ORM Foundation

[quote user="Ken Evans"][quote user="Looopy"]. the thing i am try to accomplish is that both a employee and customer can share the same login and its not mandatory that they should be able to login and its not mandatory for a person to do a login either. [/quote]  Please refer to my example. If you: 1: remove the ...

[quote user="Andy Carver"]Hi, Yes you are correct, there should be a way to do it and there isn't. ORM's Rmap algorithm stipulates that in relational-mapping a 1:1 fact type like yours with mandatory constraints either on both roles or on neither roles (as in your case), the user needs a way to input his / her preference as ...

Hi Again, Thanks for the tips Ken about the book. But still i think i will get in a situation that i don't agree on how norma generates the DDL SQL. Like now then it got the foreign keys on weblogin but i could fool the tool by adding and removing the mandatory flag and resave the model and then i get the foreign keys at customer and ...

Hi Ken, [quote user="Ken Evans"] Looopy, Maybe I'm wrong, but I get the impression that you have some notion of what the relational model "should" look like and then you are trying to work back from that to define an object-role model that fits what you think "should" be the case. [/quote] No i tried ...

[quote user="Clifford Heath"] Do you intend that an Employee who is also a Customer can have two WebLogins? You do know that there is no implicit exclusion between two subtypes as in some O-O languages? You can add an exclusion constraint if necessary. [/quote] No they should be using the same weblogin but its not mandatory that ...

[quote user="Clifford Heath"]Nothing in your model requires the FK to be in a particular direction. Just a thought; try setting Customer "Independent" in the Property pane. I think that will skew the absorption to decide that Customer is a table (while it's still making up its mind about a WebLogin). However, surely the ...

[quote user="Ken Evans"]Thanks for your question, however, as I'm sure that you know, the orm diagram you posted is not the same as that which is reflected in the relational view. The orm diagram that you posted just gives a single table. So it would be helpful if you posted both the object-role model and the relational view of that ...

I have a Employee that can have a WebLogin, those weblogin should not be connected to a Customer if they are not the same. But i will try to set it as "Independent" and se what happens. Thanks for the tip!

I have a Employee that can have a WebLogin, those weblogin should not be connected to a Customer if they are not the same. But i will try to set it as "Independent" and se what happens. Thanks for the tip!

Hi I just wonder how i can select which direction the entities so the relational View will create a DDL correctly. As you can see it do not link the Customer to WebLogin instead it Links Weblogin to Customer. If i set the RolePlayer "Customer" to mandatory and then make it not mandatory it changes direction but next time a change ...