Well, we "upgraded" to 9iR2 a few months ago, and we're all fckd up.

Firstly, we lost the ability to do CTAS on a 32K tablespace. Rather inconvenient.

Secondly, we implemented data segment compression, and now we have to keep running mods against the sys.obj$ table to prevent "block too fragmented to build bitmap index" errors.

Thirdly, after implementing data segment compression we found that you can neither ADD nor DROP columns from the table -- you have to uncompress the whole damn thing. Needless to say, this was an unpleasant surprise.

Fourthly, on our major fact tables we can NO LONGER USE BITMAP INDEXES due to a bug that Oracle say may not be fixed for our platform until 10i.

On a personal note, these problems have cost me about 200 hours with my family over the past few months, although as an hourly-rate consultant it has paid for my landscaping.

Anyhoo, at this rate our upgrade path will skip 10i and go directly to Teradata.

* sigh *