Wolfgang, point well taken, but a one-to-many seems semantically wrong as well, since it's really one-to-one and not one to many.
It seems like trading one semantically wrong statement for another... On Wed, Jan 14, 2009 at 6:48 AM, Wolfgang Trog <[email protected]>wrote: > Strictly speaking, optional items are one-to-many associations. The > semantic of an one-to-one association is 1:1 not 1:0,1. So I assume > one-to-one's are not advised because it's better to put the data in one > table to avoid the hassle with aligning id's and the join in each access. > > > > -- > > Wolfgang > > > > *From:* [email protected] [mailto:[email protected]] *On > Behalf Of *Tim Barcz > *Sent:* Dienstag, 13. Januar 2009 18:06 > *To:* [email protected] > *Subject:* [nhusers] Re: Mapping one-to-one entities > > > > Can you explain why one to one is not advised? We use one-to-one in a > non-legacy system, generally for items which are optional. The other way we > could do this would be to represent the object as a many to many, which now > structures the data in a way that is inconsistent with how we use the data. > > Again, why is one-to-one "not advised"? > > Tim > > On Tue, Jan 13, 2009 at 10:01 AM, Will Shaver <[email protected]> > wrote: > > One-to-one is not advised for new database design, but is supplied for > legacy databases. I am using one-to-one to map out the legacy databases that > I have to deal with and it works fine. I recently fixed a bug so now > one-to-one mapping with composite keys will work. > > > > -Will > > > > On Tue, Jan 13, 2009 at 2:20 AM, Adeel <[email protected]> wrote: > > > Again, for my current project which involves a legacy database, I need > to map entities who have a one-to-one relationship. This translates to > the following: An entity "person", which is stored in a "person"- > table, always has one and only one SearcProfile, which is another > entity, stored in the "SearchProfile"-table. The Searchprofile also > has a one-to-one relationship with the Person. > As I understand, using One-To-One mappings is not advised. But what > would be the fitting strategy for mapping such a relation... > > > > > > > > > > > --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "nhusers" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/nhusers?hl=en -~----------~----~----~----~------~----~------~--~---
