Re: CURSOR/FETCH vs LIMIT/OFFSET

From: Philip Hallstrom <philip(at)adhesivemedia(dot)com>
To: Charles Hauser <chauser(at)acpub(dot)duke(dot)edu>
Cc: pgsql-sql(at)postgresql(dot)org
Subject: Re: CURSOR/FETCH vs LIMIT/OFFSET
Date: 2002-05-08 20:31:39
Message-ID: 20020508133050.A20473-100000@teak.adhesivemedia.com
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Why not at the very beginning do something like "SELECT COUNT(*)..." and
store that as $totalTuples... then use limit/offset...

-philip

On Wed, 8 May 2002, Charles Hauser wrote:

> Hi,
>
> re: displaying results of query.
>
> Trying to work out details of how to let users page back and forth
> among a multi-page list of results.
>
> Problem: I need to know the total number of tuples the query would
> return in order to decide if there are more to display.
>
> 1) Use CURSOR and FETCH
>
> $res= $con->exec(
> "BEGIN WORK;
> DECLARE gene_result CURSOR FOR
> SELECT blah blah
> ORDER BY blah;
> FETCH $offset IN gene_result
> ");
>
> $result->ntuple: returns only the number set by $offset, not TOTAL for query.
>
> 2) use LIMIT OFFSET
>
> same problem,
> $result->ntuple: returns only the number set by LIMIT, OFFSET, not
> TOTAL for query.
>
> So there has to be a way to glean both the TOTAL and the SUBSET returned?
>
> Searching the postgresql archives obviously can deal with this
> http://archives.postgresql.org/pgsql-sql/
> 'Displaying documents 11-20 of total 243 found.'
>
> --
> Regards,
>
> Chuck
>
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