Thanks Helen for the interesting & useful information.

> What kind of application are you planning to write?

I think it would be described as a database application.

Of the methods you describe, two offer possiblities.
PSQL & ESQL.

I have written simple procedures so its just a matter reading up on
Cursors, to see how to accomplish what I want.
I think this approach would be the way to go when working in a single
database. The FOR SELECT...INTO...DO construct sounds like the thing
to use, (must read up on that one).

>i.e. the client has to mediate.

However, because of the need to sometimes access the same table in
different databases, ESQL may be the simplest approach.
i.e. select & store the data from DB1 then Insert/Update in DB2.

I don't use IBOBjects components yet, but the TIB_DataPump component
you mentioned sounds good.

No doubt I'll be back requesting specific help on Cursors.

Thanks again, you have given me a direction to explore

Jack