v$transportable_platform lists dataendianness for different platforms on which Oracle is available.
platform_id might be joined to v$database to determine the endianess of the data in a database.
select
to_char(platform_id, '99'),
platform_name,
endian_format
from
v$transportable_platform
order by
lower(platform_name);
--
-- 6 AIX-Based Systems (64-bit) Big
-- 16 Apple Mac OS Big
-- 21 Apple Mac OS (x86-64) Little
-- 19 HP IA Open VMS Little
-- 15 HP Open VMS Little
-- 5 HP Tru64 UNIX Little
-- 3 HP-UX (64-bit) Big
-- 4 HP-UX IA (64-bit) Big
-- 18 IBM Power Based Linux Big
-- 9 IBM zSeries Based Linux Big
-- 10 Linux IA (32-bit) Little
-- 11 Linux IA (64-bit) Little
-- 13 Linux x86 64-bit Little
-- 7 Microsoft Windows IA (32-bit) Little
-- 8 Microsoft Windows IA (64-bit) Little
-- 12 Microsoft Windows x86 64-bit Little
-- 17 Solaris Operating System (x86) Little
-- 20 Solaris Operating System (x86-64) Little
-- 1 Solaris[tm] OE (32-bit) Big
-- 2 Solaris[tm] OE (64-bit) Big