Different definitions for entity field type "very-long" for different DB systems causes DB incompatibilities, and therefore errors on import.

For example, "very-long" maps to TEXT on postgres (ie - CLOB), but it maps to VARCHAR2(4000) on Oracle.

This means if you take a JIRA export from postgres, you may not be able to import it into Oracle as some columns may contain too much data.
eg SearchRequest.description.