Re: Finding column using SQL query.

>>pg_attribute.attrelid=pg_class.oid
I am not able to find any attribute name 'oid' for pg_class.
Is this new in 8.0?
Can you construct a query to explain this?

Thanks,
Rajan


-----Original Message-----
From: email@juergen-cappel.de [mailto:email@juergen-cappel.de]
Sent: Wednesday, February 09, 2005 5:02 PM
To: Rajan Bhide
Cc: pgsql-novice@postgresql.org
Subject: Re: RE: [NOVICE] Finding column using SQL query.



You have to link like this:

    pg_attribute.attrelid=pg_class.oid

and to find the datatye of an attribute:

    pg_attribute.atttypid=pg_type.oid



HTH, Jürgen




Rajan Bhide <rbhide@starentnetworks.com> schrieb am 09.02.2005,
12:10:54:
> I tried finding relation between pg_attribute and pg_class but seems
> there is no common key between these two table.
>
> select * from pg_attribute where attrelid = (select reltype from
> pg_class  where relname = 'mytablename';  attrelid | attname |
> atttypid | attstattarget | attlen | attnum | attndims | at
> tcacheoff | atttypmod | attbyval | attstorage | attisset | attalign |
> attnotnull
>  | atthasdef
> ----------+---------+----------+---------------+--------+--------+----
> ----------+---------+----------+---------------+--------+--------+--
> ----+---
> ----------+-----------+----------+------------+----------+----------+-
> ----------+-----------+----------+------------+----------+----------+-
> ----------+-----------+----------+------------+----------+----------+-
> --------
> -+-----------
> (0 rows)
>
>
> So this is not solving my problem.
> Am I missing somethg or there is some other way to find out? Plz
> comment.
>
> Thanks,
> Rajan
>
> -----Original Message-----
> From: email@juergen-cappel.de [mailto:email@juergen-cappel.de]
> Sent: Wednesday, February 09, 2005 3:38 PM
> To: Rajan Bhide
> Cc: pgsql-novice@postgresql.org
> Subject: Re: [NOVICE] Finding column using SQL query.
>
>
>
> Take a look at the system catalogs:
>
> http://www.postgresql.org/docs/8.0/interactive/catalogs.html
>
> HTH
>
>
>
> Rajan Bhide  schrieb am 09.02.2005,
> 10:56:20:
> > Hi,
> >
> > Is there any way to find whether a particular column exists in the
> > table or not based on the column name using sql query? I have a
> > requirement where I need to find whether a column exists in the table
> > or not using SQL query.
> >
> > Thanks,
> > Rajan
> >
> > ---------------------------(end of
> > broadcast)---------------------------
> > TIP 9: the planner will ignore your desire to choose an index scan if
> your
> >       joining column's datatypes do not match