access computed field of RECORD variable

Hi,

I ran into a roadblock at the very bottom of a fairly large database
design implementation.  It will be at least messy to fix, unless there is
a neat solution.

The roadblock is:

There is a record, which may be from any of a set of similar databases.
Field names for this record are computed as strings.  Using these strings,
I need to access fields of the record.

But I can't find the syntax for it.

Now, if a record variable is a known row type, I can get a field of a
computed name.
For a generic RECORD I can get a field by putting an explicit name the code,
    (rec).FieldName1
But can one get the value of a computed field from a generic RECORD?

With
    rec   RECORD;
    field TEXT;

The following all fail:

        res := rec.field;     -- ERROR:  record "rec" has no field "field"
        res := (rec.field);   -- ERROR:  record "rec" has no field "field"
        res := (rec).field;   -- ERROR:  syntax error at or near "$2"
        res := rec.(field);   -- ERROR:  syntax error at or near "("
        res := rec."FieldName1"; -- gets field, but isn't what is needed

I also tried numerous other things that were doomed to fail.

Find an example file attached.  Just "\i" it and play with the possibilites.

Thanks!

--
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| Steve White                                             +49(331)7499-202
| e-Science / AstroGrid-D                                   Zi. 35  Bg. 20
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