Thomas Keller (6/10/2008)
In my case, it was necessary not only to show that a certain user ran a certain query at a certain time (as the trace would do), it was also necessary to show which records resulted, and the state of certain important columns at the time, hence the need for active logging from the select procedure. Also management wanted real-time info, and did not want to archive old info. Admittedly this was not a huge database, but effective normalization keeps the history table manageable.
I have had databases where we needed to be able to track data changes and be able to present a view of the data as it existed at any point in time. This is best accomplished via triggers and archive/history tables. When combined with a trace that captures who ran what query and when, you could "recreate" what a given user saw at a given point in time without having to store the actual result set returned.
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If most people are not willing to see the difficulty, this is mainly because, consciously or unconsciously, they assume that it will be they who will settle these questions for the others, and because they are convinced of their own capacity to do this. -Friedrich August von Hayek
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