Well... it depend, if you are creating a session-factory for each
persistence action, the the round-trip to read the High value is only your
last concern.
The roundtrip happen only one time per-session-factory per-table (inside
maxlow, obviously)

2009/3/26 Daniel Auger <[email protected]>

>
> Please excuse my ignorance, but can the high table reads/increments
> ever become a performance bottleneck since every session factory has
> to do a read/increment on the same table/column? I'm guessing that
> maybe in theory the answer is yes, but in practicality the answer is
> no.
>
> On Mar 26, 8:32 am, Fabio Maulo <[email protected]> wrote:
> > Ken, in NH is even better because it respect a "sequence per table".
> > An High is requested per sessionFactory per Persister...
> > Example:
> > Table-A: 101, 102,103,104......501,502....
> > Table-B: 201, 202, 203, 204... 801,802....
> >
> > 2009/3/26 Ken Egozi <[email protected]>
> >
> >
> >
> > > the way I understand it:
> >
> > > a generated 64bit ID will consist of a HI and LO 32bit values
> > > (HI*32bit+LO)
> >
> > > when a SessionFactory kicks in, it requests (and increments) the HI
> from
> > > the DB.
> > > as an outcome - every SessionFactory gets a range (using the HI) then
> > > increments the LO on each new entity.
> >
> > > On Thu, Mar 26, 2009 at 11:12 AM, Peter Morris <[email protected]
> >wrote:
> >
> > >> It is the thing that you last said, when exhaust a new Hi value is
> > >> obtained,
> > >> Lo values are incremented everytime an object is persisted.
> > >> <
> >
> > >> Ah I see, that makes sense.  I am confusing it with the other approach
> > >> where
> > >> only the exact number of IDs are requested when an update is required.
> >
> > >> Pete
> > >> ====
> > >>http://mrpmorris.blogspot.com
> >
> > > --
> > > Ken Egozi.
> > >http://www.kenegozi.com/blog
> > >http://www.delver.com
> > >http://www.musicglue.com
> > >http://www.castleproject.org
> > >http://www.gotfriends.co.il
> >
> > --
> > Fabio Maulo
> >
>


-- 
Fabio Maulo

--~--~---------~--~----~------------~-------~--~----~
You received this message because you are subscribed to the Google Groups 
"nhusers" group.
To post to this group, send email to [email protected]
To unsubscribe from this group, send email to 
[email protected]
For more options, visit this group at 
http://groups.google.com/group/nhusers?hl=en
-~----------~----~----~----~------~----~------~--~---

Reply via email to