Either the BLOB is stored with the incorrect value or the value on disk does not match the stored length on disk and an exception is raised. The BLOB was supplied as a stream value.
See this with the new TriggersTest. The text fixture will have a comment with this bug number showing how to reproduce the problem.
- is related to
DERBY-3645 Insert into selecting BLOB column twice leads to SQLException: Restore of a serializable or SQLData object of class error selecting from the table