French characters, eastern european database

Question

Hi,
I have a 11.2 database with the following settings:
NLS_CHARACTERSET EE8MSWIN1250
NLS_NCHAR_CHARACTERSET AL16UTF16
Is there any way I could insert all the french accented characters into
this database or the nls_characterset forbids that, even if the
nls_nchar_characterset can handle french accents? I created a test
table with one nvarchar2 column, but there are characters that lose
their accent after creation. (è for example). I tried it from SQLDeveloper, to eliminate nls_lang problems.
Thanks,
Krisztian

Answer 1

Using NVARCHAR2 or NCHAR for the character data types should work- the AL16 set should handle most characters, just not as many as UTF8. As long as client programs have the correct NLS_LANG setup.
If the coding gets sloppy and (tries to) save unicode values into VARCHAR2 or CHAR data types it will very likely get incorrectly translated as the data is stored, and there won't be any way to get the proper character codes back to the client.
The N{types} will also consume more storage space- up to 4 bytes per character- try this out, and see the user_segments.bytes for the tables:
create table ctest ( chartest varchar2(1000) )
  -- tablespace <tblspc>
create table ntest ( nchartest nvarchar2(1000) )
  -- tablespace <tblspc>
begin
   for i in 1..50000 loop
      insert into ctest values (  rpad( 'z', 1000, 'a'));
      insert into ntest values (  rpad( 'b', 1000, 'b'));
   end loop;
end;
select SEGMENT_NAME, sum( BYTES ) / 1024 / 1024 as mb from user_segments
where segment_name in ('CTEST','NTEST') group by SEGMENT_NAME