The EPSG factory works as expected on Derby. But attempt to use the factory on PostgreSQL sometime produces the following error message:
The issue occurs in expressions like coord_ref_sys_kind LIKE 'projected%' with the coord_ref_sys_kind column defined as an enum when Apache SIS is using PostgreSQL. The fix is to cast the CRS Kind enum to VARCHAR(24). The bug does not happen in Derby because that column is already a VARCHAR(24) since Derby does not support enums.