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From "Øyvind Harboe" <oyvind.har...@zylin.com>
Subject Re: Relationships across databases
Date Wed, 20 Jun 2007 21:17:25 GMT
On 6/20/07, Mike Kienenberger <mkienenb@gmail.com> wrote:
> If I recall, it means that for a given query select ID from table1 t1,
> table2 t2 where t1.id = t2.id, you will have to do something like
> this:
>
> List list = select T1_ID from table1;
> for each item in list
> {
>      select * from Table2 where t2.id = item.t1_id
> }
>
> The multiplication is number of the queries issued, not the memory used.
>
> Obviously, the simple case above could be optimized using an IN
> statement, but anything that wasn't trivial could not be.

How can the application do this more efficiently than Cayenne could?

Cayenne can only said to be inefficient if the application could,
somehow, do this more efficiently, right?


-- 
Øyvind Harboe
http://www.zylin.com - eCos ARM & FPGA  developer kit

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