* Global temporary tables are created in the schema's default temporary tablespace. In fact, there is no tablespace placement option.

So in many respects, you get the best of both worlds: table-like control, along with automatic temporary segment management.

While the Oracle documentation is not entirely clear, it does seem to indicate global temporary tables do not generate any redo. While my experiments3 showed this to be incorrect, even the worst case scenario achieved a remarkable 43% redo reduction. For example, with a row size of 750 bytes, redo was consistently reduced by 68.1%. And even more important, as the row size increased, so did the redo savings.