Re: How to write such a query
> How to find what the primary key (or UNIQUE identifier) value is
> for row 5 in the recordset?
You're missing the point: as mentioned before, there is no "row 5". To
update the 5th record that you've fetched, you increment a counter each time
you fetch a row, and when you read #5, do an UPDATE X SET field1 = 'blarg'
WHERE id = <thekeyvalue>;
It seems worth mentioning for benefit of the OPs question that there _is_ a way to get a row number within a result set. Understanding and making good use of that is an additional matter.
SELECT X.field1, Y.field2,row_number() OVER () from X, Y WHERE X.id = Y.id -- ORDER BY ____?
That row number is going to depend on the order of the query, so it might or might not have any meaning. But if you queried with a primary key and a row number, you could then tie the two together and make an update based on that.
Cheers,
Ken
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