Oracle does work in a raw partition, however, Oracle does NOT require a raw partition. Oracle will work fine on a free UNIX Slice 3 partition.
Oracle Tech Support suggests using a Slice 3 partition instead of a Raw partition. They claim the increase in speed with a Raw partition is not worth the trouble for Macintosh users to deal with UNIX directly. It's much easier for most users to be in the familiar Macintosh environment to manipulate their Oracle Database files.
Below are some of the advantages and disadvantages of both:
Raw Slice
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Advantages:
* Fastest access to hard drive (no file system overhead)
Disadvantages:
* Have to use tar or other UNIX utilities to backup partition
* Can't use Finder to see directory structure
Free UNIX Slice 3
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Advantages:
* Can use Retrospect to backup the partition
* Can use finder to navigate file structure
Disadvantages:
* Slightly slower
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