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Date: Tue, 4 Aug 2015 04:43:25 -0700 (PDT)
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Subject: Re: Design of cross referring types/classes and proper usage of
 containers
From: Serge Robyns <serge.robyns@gmail.com>
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Date: 2015-08-04T04:43:25-07:00
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On Monday, 3 August 2015 18:22:20 UTC+2, Dmitry A. Kazakov  wrote:
> 
> When aggregation does not work, which is the case when relationships are
> complex, you keep them outside. You create maps
> 
>    Client to [not null access] Subscription
>    Subscription to [not null access] Client
> 
> etc. And search the maps if you have one and need another. For the map you
> can use hash or binary searched container.
> 
> Note that aggregation is fragile. If you have a suspicion that
> relationships may go chaotic, don't aggregate.
> 
> --

Thank you for the advice.  You confirm my intuition, which also makes the implementation more in 1 to 1 with the storage data model, as the db will be used for other purposes as reporting.  Today, I'm indeed using map containers for most of these.

Is there any point of attention when using access variables to containers?  Any risk of dangling pointers because of operations on the elements of the map (updates)?

Regards,
Serge