Regarding the first problem (limiting results to page-size subsets with MS SQL), I use a nested select that I picked up from a DBA much craftier than myself, and I use it in code like the following (using an arbitrary 'parts' table with fields 'partno' and 'custno'):
my $perpage = '25';
my $curpage = $q->param('curpage') || 1; # Assumes $q is a CGI object
my $custno = $q->param('custno');
my $offset = $curpage*$perpage;
my $orderby = 'partno';
my $totalcount = @{ $dbh->selectrow_arrayref(
qq{SELECT count(*) FROM parts WHERE custno = '$custno'}
) }[0];
# Next four lines limit the results of the LAST page's data, in case o
+f a short page.
my $reccount = $perpage;
if (($totalcount - $offset) < 0) {
$reccount = $totalcount-$offset+$perpage;
}
# Now build the select (read inside out)
(my $select = <<ENDOFSQL) =~ s/^\s*#.*\n//gm;
SELECT * FROM (
SELECT top $reccount * FROM (
SELECT top $offset *
FROM parts WHERE custno = '$custno'
ORDER BY
$orderby DESC
) top_data
ORDER BY $orderby ASC
) page_data
ORDER BY $orderby DESC
ENDOFSQL
my $dataref = $dbh->selectall_arrayref($select,{Columns=>{}}) || die '
+Whoops!';
The main select gets everything past the $offset, it's then wrapped in a select that flips the order and gets just the TOP $reccount of the first set, in turn that's wrapped in a last outer select which just flips the order back right-side-up.
Anyone else use something like this?
I know I'm wasting a few cycles doing the $totalcount lookup, but I also use that number to generate the page navigation links. In fact, I might ask for critique of my navLinks() sub here at some point, I think it's kinda nifty.
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