Most of FishEye's data is stored on disk, including repository caches and search indexes. The DB houses mostly configuration data, including users, their settings and permissions. If you use Crucible with FishEye, the review data is stored in the DB as well.
Hope this helps.
Update: Our AMA with @Serhat Can is complete! Thank you everyone for taking the time to write your questions and participate, you are the folks that make the community enriching and fun! If...
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