Re: CURSOR/FETCH vs LIMIT/OFFSET - Mailing list pgsql-sql

From Philip Hallstrom
Subject Re: CURSOR/FETCH vs LIMIT/OFFSET
Date
Msg-id 20020508133050.A20473-100000@teak.adhesivemedia.com
Whole thread Raw
In response to CURSOR/FETCH vs LIMIT/OFFSET  (Charles Hauser <chauser@acpub.duke.edu>)
List pgsql-sql
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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