> Computed field will be computed only when you select it. E.g.
>
> CREATE TABLE T (
> pk INTEGER ...,
> data1 COMPUTED (select data1 from spGetData1(T.pk)),
> data2 COMPUTED (select data1 from spGetData2(T.pk)) );
>
> SELECT pk, data1 FROM T;
>
> -> only spGetData1(T.pk) will be computed, not spGetData2(T.pk).

Strangely, I cannot seem to get the above COMPUTED field declaration to
work. FB complains about token unknown 'select'. Apparently a computed
field can only contain simple expressions (i.e. data1+data2). I have
always thought that the 'expr' part could be anything as long as it is a
singleton select....

TIA,
sugi.