Hello, Gugui!

Tuesday, November 13, 2012, 12:43:16 AM, you wrote:

G> I have a fdb with 400 Mb and Charset defined to NONE,

"default database charset" is declarative only, and istructs server to
use that charset for newly created character fields with no charset
specified.

So, you can create field with needed charset at any time in any
database.

G> so I need to change it to UTF-8 (to work with Lazarus/Zeos)
G> what is the best way to do that ?

G> Is there a way to restoring it with utf-8 already ?

no, only pump. unicode uses up to 4 bytes per character.
Charset NONE uses only 1 byte per character.
So, field char/varchar(20) can store 20 characters for NONE,
and from 20 to 5 characters for UTF8, depending on how much bytes
each character have.
Thus, you may need to increase your character fields size.

--
Dmitry Kuzmenko, www.ib-aid.com