Обсуждение: Reg: Records Size

On 11/11/05, sandhya <sandhyar@amiindia.co.in> wrote:
> please...tell me if there is possibility of finding  out the size of a
> record in the specified table.
> Is there any built in function to know the size of each record by passing a
> query?
> I need this Inorder to allocate the memory after retrieving the records.
> Pls suggest me.

You are not giving enough information.  What programming language are
you using?  What do you mean by a "record"?  Do you want to know much
memory to allocate to store each tuple resulting from a query?  If so,
that will obviously depend on the type of each column and the size of
each field.

  John Barham

Hi John ,
Thank you.
I am using C.
Yes i mean to allocate memory of each tuple resulting from a query.
Is there any function which gives the size of a tuple?
If so...Please tell me/Tell me how to proceed to do that?

Thanks&Regards,
Sandhya R




----- Original Message -----
From: "John Barham" <jbarham@gmail.com>
To: "sandhya" <sandhyar@amiindia.co.in>
Cc: "postgre" <pgsql-admin@postgresql.org>; "Sivakumar K"
<sivakumark@aztec.soft.net>
Sent: Friday, November 11, 2005 2:40 PM
Subject: Re: [ADMIN] Reg: Records Size


On 11/11/05, sandhya <sandhyar@amiindia.co.in> wrote:
> please...tell me if there is possibility of finding  out the size of a
> record in the specified table.
> Is there any built in function to know the size of each record by passing
a
> query?
> I need this Inorder to allocate the memory after retrieving the records.
> Pls suggest me.

You are not giving enough information.  What programming language are
you using?  What do you mean by a "record"?  Do you want to know much
memory to allocate to store each tuple resulting from a query?  If so,
that will obviously depend on the type of each column and the size of
each field.

  John Barham

> I am using C.

Lucky you.  I use Python. ;)

> Yes i mean to allocate memory of each tuple resulting from a query.
> Is there any function which gives the size of a tuple?
> If so...Please tell me/Tell me how to proceed to do that?

From the manual:
http://www.postgresql.org/docs/8.0/interactive/libpq-exec.html#LIBPQ-EXEC-SELECT-INFO
will give you everything you need.

  John