Subject Re: [Firebird-Java] Jaybird and XWiki
Author Mark Rotteveel
On 29-11-2012 14:12, mariuz wrote:
> On Sat, Nov 03, 2012 at 02:13:09PM +0100, Mark Rotteveel wrote:
>> I had a look at getting XWiki to run on Firebird, and with some minor
>> changes to the hbm.xml files, an improved Dialect and unfortunately a
>> change to Jaybird itself I got it running. Most likely the improved
>> Dialect is not required, although I need to test that a bit more.
>> In the current Jaybird versions there is a bug in the handling of Clobs
>> (when the Clob is set using a non-Jaybird Clob (as Hibernate appears to
>> do), or with a Reader). See
>> I will see if there is a way to get Hibernate to not use the
>> get/setClob, but just get/setString instead (as that should be handled
>> transparently with Jaybird). Otherwise a new release of Jaybird is
>> required to get things to work.
>> Mark
> I need hibernate and firebird for a university project
> do you have any tips or howto?

There is no how-to yet, I have to find the time and energy to write one.
As I said, most things will just work, except for Clob as indicated in
the email above.

Another thing you need to take into account is that the maximum size of
one column (except blobs) is 32KB, and 64KB for the entire row

For a CHAR column this means the maximum width is 32768 characters when
using a single byte character set (eg ISO8859_1), but only 8192 for a
UTF8 character set. Firebird unfortunately takes the maximum size of a
UTF8 character when deciding the max width, even though the four byte
sequences in UTF8 are rarely used. For a VARCHAR column you have two
bytes less, so you have 32766 and 8191 characters respectively.

Other than that I am currently not aware of other major issues. And even
though the current dialect shipped with Hibernate is lacking some
features, it will probably be enough for most use cases.

If you run into any specific problems, just ask.

Mark Rotteveel