Oracle 7's cost based optimizer

This is probably a FAQ but since there isn't one:

This is the first week that we have had Oracle 7 running in production here and it has been quite a week. We have seen forms and reports that, though not 'snappy' in the first place, have taken quite a hit in performance. System tuning was immediately begun and addressed some of it. Yesterday one of our DBAs tracked down another who had made the same transistion and taken the same performance hit. They tracked it down to the cost-based optimizer. Last night it was turned off here and we are awaiting results.

In the mean time what experiences have others had with Oracle 7 and the new optimizer? What steps have you taken to optimize performance? Are there other gotcha's out there?

TIA
// dirk tolson
// dirkt_at_srs.gov
Received on Thu Mar 03 1994 - 16:30:00 CET