Re: [boost] Review request: indexed_set

From: Jonathan de Halleux (dehalleux_at_[hidden])
Date: 2003-09-11 04:43:31

[snipped]

Very (very) interresting. I know you mention that "it is not intended to 
provide a full-fledged relational database framework" but could it be 
possible to support basic join operations.

Suppose that we have:

struct client
{
     int id;
     bool operator<(const client& e)const{return id<e.id;}
};

struct order
{
     int id;
     int client_id; // foreign key to client
     bool operator<(const order& o)const{return id<o.id;}
};

Ok, so the indexed sets for these would be:
typedef indexed_set<
   client,
   index_list<
     unique<identity<client>
     >
 > client_set;

typedef indexed_set<
   order,
   index_list<
     unique<identity<order> >,
     non_unique< tag<client>, member<order,int,&employee::client_id> > >
 > order_set;

Now that I have my two sets, I would like to get all the orders done by a 
particular client ?

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Jonathan de Halleux, Research Assistant
Center for Systems Engineering and Applied Mechanics (CESAME)
Universite catholique de Louvain
Batiment Euler , Av. Georges Lemaitre, 4 Tel : [phone]
B-1348 Louvain-la-Neuve Belgium
E-mail : dehalleux_at_[hidden]
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