Re: [INTERFACES] the last row in a table

From: "Thomas G(dot) Lockhart" <lockhart(at)alumni(dot)caltech(dot)edu>
To: hoelc(at)pd(dot)jaring(dot)my
Cc: pgsql-general(at)hub(dot)org
Subject: Re: [INTERFACES] the last row in a table
Date: 1999-03-09 15:20:14
Message-ID: 36E53C2E.C2E59616@alumni.caltech.edu
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> I am developing a database with PostgreSQL in Linux, and using ecpg to
> write the C program to communicate with the database.
> One of my application need to get the data from the last row in a
> table. Is there any function or command that can tract which is the
> last row of data in a table?

SQL is a set-oriented language. One should probably not assign any
significance to a storage order of rows.

It *is* possible to order the results of a query, and then your
first/last qualities do have meaning. I would suggest ordering your
query (perhaps on a "row update time" if by "the last row" you mean "the
more recently entered row") using the "DESC" qualifier in the ORDER BY
clause, then use a cursor to pick up the first row returned.

Good luck.

- Tom

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