Re: reg:lo_write

Hi Sandhya.

On 6/22/06, sandhya <sandhyar(at)amiindia(dot)co(dot)in> wrote:
> Hi Macro..
> If i assign my lobj_fd(say LO file descriptor) to one Global int.
> But will my lo_write work if i pass that global int inplace of lobjfd....

Yes, I think so.

> One more thing...It should be in "begin" and "end" sessions right!

If you mean inside a single transaction, yes, the lobj_fd is sensible
within one transaction.

> How can i open a LO in many places and write the content into it.....Will it
> get appended to the previous content?

If you have to open and append to the previous content, you could use
other lo_lseek, and pass it SEEK_END, so that you will position to the
end of the LO. At that point, you could "append" to the end of the LO.

> You said two different file descriptors i will be having?How to overcome
> it?Any suggestion pls
>
> Anybody please give me suggestion how can i over come this problem?So that i
> can proceed further
>
>
>
>
> ----- Original Message -----
> From: "Marco Bizzarri" <marco(dot)bizzarri(at)gmail(dot)com>
> To: "sandhya" <sandhyar(at)amiindia(dot)co(dot)in>
> Cc: "Postgres" <pgsql-admin(at)postgresql(dot)org>
> Sent: Thursday, June 22, 2006 1:43 PM
> Subject: Re: [ADMIN] reg:lo_write
>
>
> > I'm not sure, but I think you will have problems. As far as I can
> > understand, largeobject semantics is similar to files. Therefore, you
> > open an existing LO, and you obtain a file descriptor, which will
> > point (I think) at the start of the LO. If you write something, the
> > file descriptor will be moved accordingly. If you open again (i.e. you
> > issue another lo_open), you will have another file descriptor for the
> > same LO, which will be at the start of the LO, and you will overwrite
> > your previous LO.
> >
> > Please take care with these advices as I'm not a PostgreSQL expert,
> > just reporting some experience.
> >
> > Regards
> > Marco
> >
> > On 6/22/06, sandhya <sandhyar(at)amiindia(dot)co(dot)in> wrote:
> > >
> > >
> > > Hi,
> > >
> > > If i use lo_write in different function to write data into an
> object,Will
> > > there be any problem?
> > > like,
> > > I open my object and add data into it and in another function if i again
> > > open the same object and add data....It will append to the previous
> content
> > > right!Am i wrong?
> > >
> > > If i wants to append the content to the present object is there anything
> i
> > > need to do?
> > > Please help me in doing this................
> > > I am unable to see the image which i am exporting...
> > > Thank you,
> > > Sandhya
> > >
> >
> >
> > --
> > Marco Bizzarri
> > http://notenotturne.blogspot.com/
> >
> > ---------------------------(end of broadcast)---------------------------
> > TIP 9: In versions below 8.0, the planner will ignore your desire to
> > choose an index scan if your joining column's datatypes do not
> > match
> >
>
>
>

Regards
Marco

--
Marco Bizzarri
http://notenotturne.blogspot.com/