> Luis,
>
> I've looked quite hard at your problem (as originally posted) and I

think

> you have your master-detail relationships back-to-front for doing

what you

> ask to do.
>
> I think DatasetC is, for your requirements, the detail dataset of

an

> optional master-detail relationship. I believe what you want to do

with

> the three datasets can be done quite simply by swapping the

Mastersource

> and MasterParamLinks between DatasetA and DatasetB as alternative
> masters. Don't use a table component for DatasetC, use a query:
>
> SELECT idC, A, B, ....
> from TableC
> where A = :ParamA
> and B = :ParamB
>
> When DatasetA is the master, ParamA is the MasterParamLink to

DatasetA.idA

> and ParamB gets its value from DatasetB.idB; and when DatasetB is

the

> master, ParamB MasterParamLinks to DatasetB.idB and ParamA gets its

value

> from DatasetA.idA.

Hello Helen:

I don't understand exactly what you want I do.

I think my 2 masters are not alternative. Always I need a
combination of the 2 masters (1 field of the first master, and 1
field of the second master), give me the results of the detail.

I tested your code in my program:

SELECT idC, A, B, ....
from TableC
where A = :ParamA
and B = :ParamB

But I can have only one MasterSource, and the result than I get is
empty for me if I write the second condition of the where.

For now I have find another solution, doing another combination of
tables, but I'm interesting in your solution that seems very good,
and it's possibly to solve another problems of this type.

Can you explain a little more with more detail?

Thanks,