Firebird 3.0

[IBExpert]

hier ein beispiel auf Basis der IBExpert Demodb db1.fdb

Code:

execute block
returns
(customer varchar(80),
total numeric(18,2))
as
declare variable customer_id bigint;
begin
  for
    select customer.id, customer.firstname||' '||customer.lastname
    from customer
    into :customer_id,:customer
  do
  begin
    execute statement ('select coalesce(sum(orders.netamount),0) from orders where orders.customer_id=:customer_id') (customer_id:=customer_id)
    on external  'LOCALHOST/3050:C:\db\DB1.FDB'
    as   user 'SYSDBA' password 'masterkey'
      into :total;
    suspend;
  end
end