It is important to keep in mind that data is not stored "in" ArcSDE -- it's the database that
stores data, and ArcSDE just gives ArcGIS access to data, in both unversioned and versioned
form.
File geodatabase is fine, but you should keep well clear of shapefile for data transfer from
Oracle to Oracle -- it will mangle your attribute column names (limiting them to 10 characters),
lose all timestamp column resolution below day, encode all NULL numeric values as zeros, clip
all VARCHAR strings at 254 length, and fail to transfer CLOB, NCLOB, and BLOB columns.
ASCII is far more reliable than shapefile for transfer of database rows, and FGBD is easier
to use, and straight database export is easiest (though you will likely want to stage the simple
feature classes transferred by EXP/EXPDP/RMAN and copy from there into full geodatabase
form, especially if you want to migrate to SDE.ST_GEOMETRY).
- V