Thread: binary data & LOBs

Hi,

Am I correct in impression that the only way you can store binary data
(meaning data that could have all control characters including \0 in it)
is using Large Objects interface? I have tried bytea and text, both
truncate string on receipt of \0...

Also, what's physical storage size of a LOB? Does it always occupy entire
page? Or they are bunched together in rows?

I'm storing mostly small (<4096 bytes) strings but they are all binary.
I'd like to know what's the best way to do that.

Thanks
-alex

I have a database in a PC with linux and I try to connect from other PC with
linux too, when I try to do a query from command line with psql and the -u
option :

    psql -d obrascop -c "select * from obras" -hpedidos -u

I get the following error if i suply an user that exists in /etc/passwd

    Connection to database 'obrascop' failed.
    Password authentication failed for user 'postgres'

But if i connect with an user that only exists in PostgreSQL it works
Can someone tell me why

I have the following line in pg_hba.conf
    host         all         192.168.0.15  255.255.255.255   password
where 192.168.0.15  is the host from which I try to connect.


Thanks
Guillermo

I used
 select mls,city,price,numbed,fb,ohsdate,ohystime,ohetime,address,dir,rem,
       apid,brokerid from mls where ohflag>0 and ohdate >= 'TODAY'

it works thro psql, but when I use it through dbi, it does not work.
note that the query without >='TODAY' works fine:
 select mls,city,price,numbed,fb,ohsdate,ohystime,ohetime,address,dir,rem,
       apid,brokerid from mls where ohflag>0

anybody ideas? thanks in advance!

> > Guillermo Iglesias wrote:
> >   >I have a database in a PC with linux and I try to connect from other PC with
>
> >   >linux too, when I try to do a query from command line with psql and the -u
> >   >option :
> >   >
> >   >    psql -d obrascop -c "select * from obras" -hpedidos -u
> >   >
> >   >I get the following error if i suply an user that exists in /etc/passwd
> >   >
> >   >    Connection to database 'obrascop' failed.
> >   >    Password authentication failed for user 'postgres'
> >   >
> >   >But if i connect with an user that only exists in PostgreSQL it works
> >   >Can someone tell me why
> >   >
> >   >I have the following line in pg_hba.conf
> >   >    host         all         192.168.0.15  255.255.255.255   password
> >   >where 192.168.0.15  is the host from which I try to connect.
>
> > Oliver Elphick wrote:
>
> > PostgreSQL password authentication has nothing to do with /etc/passwd.
> >
> > The only users who can access PostgreSQL are those known to it
> > (listed in pg_shadow).  These usernames bear no necessary connection
> > with names in /etc/passwd.
> >

I know that the only  users who can access PostgreSQL are those known to it
(listed in pg_shadow) and when psql ask me to enter an username I supply one
existing in pg_shadow as 'postgres' but if the user is present in /etc/passwd too,
then I get the error. This error doesn't appear when I write an username that
doesn't exist in /etc/passwd

Thanks
Guillermo

Guillermo Iglesias wrote:
  >I have a database in a PC with linux and I try to connect from other PC with
  >linux too, when I try to do a query from command line with psql and the -u
  >option :
  >
  >    psql -d obrascop -c "select * from obras" -hpedidos -u
  >
  >I get the following error if i suply an user that exists in /etc/passwd
  >
  >    Connection to database 'obrascop' failed.
  >    Password authentication failed for user 'postgres'
  >
  >But if i connect with an user that only exists in PostgreSQL it works
  >Can someone tell me why
  >
  >I have the following line in pg_hba.conf
  >    host         all         192.168.0.15  255.255.255.255   password
  >where 192.168.0.15  is the host from which I try to connect.

PostgreSQL password authentication has nothing to do with /etc/passwd.

The only users who can access PostgreSQL are those known to it
(listed in pg_shadow).  These usernames bear no necessary connection
with names in /etc/passwd.

--
Oliver Elphick                                Oliver.Elphick@lfix.co.uk
Isle of Wight                              http://www.lfix.co.uk/oliver
               PGP key from public servers; key ID 32B8FAA1
                 ========================================
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      and I will give you rest. Take my yoke upon you, and
      learn of me; for I am meek and lowly in heart; and ye
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                                 Matthew 11:28,29