> -----Original Message-----
> From: Dmitri Colebatch [mailto:[EMAIL PROTECTED]]
> Sent: Monday, February 11, 2002 4:43 PM
> To: [EMAIL PROTECTED]
> Subject: Re: versioning on top of entity beans
> 
> 
> In my case, A owns B, and controls all access to B.  So A is 
> versioned, there may be duplicate copies of Bs around, for different
> versions of A, and then I pick a point to create a new 
> version of A, and close off that version.
> 
> so in A I have
>   a-pk
>   version
>   foo
>   bar
> 
> and in B
>   b-pk
>   a-fk
>   abc
>   def

So if a-pk and b-pk are UUIDs and you create new ones for each new version, how do you 
relate one version to another? How do you tell that a-pk1 and a-pk2 are different 
versions of the same item? If you had a-pk and version as the compound PK then you can 
easily tell that if a-pk is the same for two entities, that they are different 
versions of the same entity.

You could have this instead:

In A
uuid
a-id
version
foo
bar

where uuid is the PK, and you have a unique index on (a-id, version) so you can use 
a-id as the common thread between versions.

> 
> and a method in A
> 
>   A newVersion();
> 
> which returns a deep copy of A, but wth a new version.  My 
> slsb, which controls all access to A, ensures that new versions are
> created as required, and not modified.
> 
> how is it sounding?
> 

Good so far, if you can guarantee that all access to the entities goes through the 
SLSB. Do you version control B? It looks like no....


> cheesr
> dim
> > 

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