From: Michael Meskes <meskes@postgresql.org>
To: hoelc <hoelc@pd.jaring.my>
Cc: PostgreSQL Interfaces <pgsql-interfaces@postgresql.org>
Subject: Re: [INTERFACES] the last row in a table
Date: Tue, 9 Mar 1999 20:30:57 +0100
Message-ID: <19990309203057.A447@gmx.net> (raw)
In-Reply-To: <36E50F4A.CB527B78@pd.jaring.my>
References: <36E163D7.CD95C55A@pd.jaring.my>
<87emn1fwsq.fsf@tolikus.hq.aaanet.ru>
<36E50F4A.CB527B78@pd.jaring.my>
On Tue, Mar 09, 1999 at 08:08:43PM +0800, hoelc wrote:
> I am developing a database with PostgreSQL in Linux, and using ecpg to write the
> C program to communicate with the database.
Nice to hear that. :-)
> One of my application need to get the data from the last row in a table.
Now that statement is sort of a problem. In a relational model there is no
order of tuples in a relation. You can simulate this via a unique key of
course or maybe use the OID. Or do you mean the last tuple of a query?
> Is there any function or command that can tract which is the last row of data in
> a table?
Once you opened a cursor you can move it to the end of the query via the
move command. I never used this feature but I take it this is how it is
supposed to be. Afterwards you can fetch one record backward.
Michael
--
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To: pgsql-interfaces@postgresql.org
Cc: meskes@postgresql.org, hoelc@pd.jaring.my
Subject: Re: [INTERFACES] the last row in a table
In-Reply-To: <19990309203057.A447@gmx.net>
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