Skip site navigation (1) Skip section navigation (2)

Re: [GENERAL] OIDs - file objects, are damaged by PostgreSQL.

From: "Purusothaman A" <purusothaman(dot)a(at)gmail(dot)com>
To: "Richard Huxton" <dev(at)archonet(dot)com>
Cc: pgsql-general(at)postgresql(dot)org, pgsql-admin(at)postgresql(dot)org
Subject: Re: [GENERAL] OIDs - file objects, are damaged by PostgreSQL.
Date: 2007-05-23 14:56:21
Message-ID: 3650d0d50705230756g5fdf8bdava3de463eb6f82ad9@mail.gmail.com (view raw or flat)
Thread:
Lists: pgsql-adminpgsql-general
Dear Richard Huxton,

Thanks for your quick reply.

only the first 3 values(HX, MASK, Rockey4ND) are file object's oid value.
the other two are are not oid values.

I have shown original output values displayed by postgresql client.

I can explain more.

1. HX is a XML file. after downloading that file I opened that file in word
pad application.
In that I have noticed that nearly 20 characters of last line lost.
2. Rockey4ND is a dll file. I was unable to use that dll in my application.

In both cases, I checked file size. Corrupted files are smaller when compare
to the original one what I uploaded to postgresql.

Usually this problem arises only after the database become large.

Any suggestion to rectify this problem would be nice of you.

Thanks.

Regards,
Purusothaman A

On 5/23/07, Richard Huxton <dev(at)archonet(dot)com> wrote:
>
> Purusothaman A wrote:
> > Thanks Richard Huxton for your reply.
> >
> > I use client side api for uploading and downloading files.
> >
> > Its not happening immediately. But when database grows with data, file
> > object got corrupted.
>
> Yes, but *HOW* - is it a different file, length is different, what?
>
> > My table structure is as follows.
> >             Table "public.conf"
> > Column |          Type          | Modifiers
> > --------+------------------------+-----------
> > key    | character varying(50)  | not null
> > value  | character varying(100) |
> > Indexes:
> >    "conf_pkey" PRIMARY KEY, btree ("key")
> >
> > Content of this table is,
> >         key         | value
> > ---------------------+--------
> > HX                  | 101800
> > MASK                | 101801
> > Rockey4ND           | 101802
> > Threshold           | 60
> > Authentication Mode | 2
> > (5 rows)
> >
> > In the above, value of HX, MASK, Rockey4ND is 101800, 101801, 101802
> (which
> > was returned by lo_import());
>
> I find it unlikely that "2" and "60" were returned by lo_import() as
> OIDs available for large-objects. You've either got:
> 1. Some other part of your application(s) overwriting "value"
> 2. Old data still in "value"
> 3. On-disk corruption due to crashes/hardware malfunction.
> 4. You're not showing real values
>
> > Actually for some peculiar reason I  kept "Value" field as var char
> instead
> > of oid. (this could be reason?...)
>
> Hmm - well it's clearly not right, but I don't see how it can cause
> errors like this.
>
> > This problem occurs only few weeks after uploading files.
>
> You still haven't said precisely what the problem is.
>
> --
>    Richard Huxton
>    Archonet Ltd
>



-- 
http://PurusothamanA.wordpress.com/

In response to

Responses

pgsql-admin by date

Next:From: Richard HuxtonDate: 2007-05-23 15:47:40
Subject: Re: [GENERAL] OIDs - file objects, are damaged by PostgreSQL.
Previous:From: Joshua KramerDate: 2007-05-23 14:35:35
Subject: Re:

pgsql-general by date

Next:From: André VolpatoDate: 2007-05-23 15:06:59
Subject: Re: Faster data type for one-length values
Previous:From: Leif B. KristensenDate: 2007-05-23 14:52:19
Subject: Re: Sequential scan from simple query

Privacy Policy | About PostgreSQL
Copyright © 1996-2014 The PostgreSQL Global Development Group