Re: Firebird 3 by default [was: minutes of ESC call ...]

On Tue, Nov 29, 2016 at 11:35:56AM +0000, Caolán McNamara wrote:
> On Fri, 2016-11-25 at 11:13 +0100, Lionel Elie Mamane wrote:
> > On Thu, Nov 24, 2016 at 04:46:29PM +0000, Michael Meeks wrote:

> > > * Release Engineering update (Christian)
> > >         + Late features:
> > >             + Firebird by default ?
> > >                 + lots of missing features & big bugs fixed
> > > recently. (Lionel)
> > >                 + all of the blockers that were mentioned on
> > > tracking bug fixed.(Lionel)

> Is it technically plausible to import migrate existing hsqldb
> databases into firebird (without the use of hsqldb/java) ?

It requires making a read-only parser for the HSQLDB "cached" table
data format in another language than Java. Most definitely possible,
the format may even be better documented than "read the source code".

While you are not the first one expressing that wish, I'm not aware of
anybody planning to actually implement that.

The data definition (the name and structure of the tables) is just an
SQL script in the ZIP structure of the .odb, so in principle you just
replay that against Firebird with the firebird engine... The devil is
in the details: If we run into places where the HSQLDB SQL dialect is
not a subset of the Firebird SQL dialect, we'll have to deal with
those places in some way. And suddenly we have to parse, and
"understand", at least to some point, the saved HSQLDB SQL script to
convert it to Firebird SQL. <shrug>

Embedded HSQLDB databases by very old OpenOffice versions don't use
the HSQLDB "cached" table data format, but the data itself was also in
the SQL script. This was changed for performance reasons.

-- 
Lionel