Just be careful if your updating a column with a bitmap index on.
Because the smallest part of a bitmap index that can be locked is a bitmap segment (up to half a block). This actually contains a number of rows, so, if you have some parallel updates (like we have) - even though you may be updating records on say a primary key, you may still get deadlocking issues due locking on the index.

Bitmap indexes were put on our system ages ago to help performance, but they've introduced a whole host of problems - so the application was coded around it (i.e. commit's in cursor loops to stop locking), and now this is introducing snapshot too old.

Terry