Re: Tuple changes from relfilenodes

>> Are you looking for statistics or the actual prior versions of
>> rows?
>
> I'm looking for actual versions of row data. What I want to
> achieve as a final result is a kind of data change history.

We just use ON DELETE rules on the tables where we want to maintain a history. In most cases, we just copy the old
recordto the archive table which has an additional timestamp column with a default of NOW() to indicate the date of
archival.In one case, where the table schema is large, changes are "frequent" and the changes are often minimal, we
onlyarchive a small subset of data based on what is changing. If the changes affect columns outside of the small
subset,then we archive the whole record. 

Bill MacArthur