>This is the easiest, and probably the best way to do this.
>

>Update yourtable set field1=data1, field2=data2,...;
>  where uniqfield1=uniqdata1 and uniqfield2=uniqdata2 and uniqfield3=uniqdata3
>if _tally=0 && No records found, so this is a new record
>  Insert into yourtable (field1, field2... , uniqfield1, uniqfield2, uniqfield3);
>    data (data1, data2, ... ,uniqdata1, uniqdata2, uniqdata3)
>endif

Looks like a good idea.

What if we work with buffered tables? We may still need a candidate index.