[FishEye Knowledge Base]
There is a known issue with FishEye 2.0.x and very long comments when migrating your database to MySQL.In some circumstances, this might result in truncation of very long comments, causing data loss.
Depending on your configuration, you may see an error message like this while migrating to MySQL, causing the migration to fail:
You may not see the message if you are running MySQL with default settings.
For more information, see the JIRA issue.
If your data contains very long comments or review descriptions (longer than 21,845 multibyte unicode characters), consider avoiding use of MySQL until this issue is resolved fully. Alternatively, use PostgreSQL or the default (built-in) HSQLDB database.
The FishEye developers are actively working on a solution to this problem and it will be addressed in an upcoming FishEye point release.
If you require assistance in resolving the problem, please raise a support request under the FishEye project.