From ec90db43112030f0847754ccdfa7d0952f97c4a6 Mon Sep 17 00:00:00 2001
From: vfilippov <vfilippov@6955db30-a419-402b-8a0d-67ecbb4d7f56>
Date: Tue, 17 Feb 2009 10:30:13 +0000
Subject: [PATCH] Bug 40933 faster way iterating over attachments

git-svn-id: svn://svn.office.custis.ru/3rdparty/bugzilla.org/trunk@136 6955db30-a419-402b-8a0d-67ecbb4d7f56
---
 Bugzilla/Install/DB.pm | 18 ++++++++++++++----
 1 file changed, 14 insertions(+), 4 deletions(-)

diff --git a/Bugzilla/Install/DB.pm b/Bugzilla/Install/DB.pm
index daaceb09b..223993fe1 100644
--- a/Bugzilla/Install/DB.pm
+++ b/Bugzilla/Install/DB.pm
@@ -2431,16 +2431,26 @@ sub _copy_attachments_thedata_to_attach_data
                 unless $attachdir && -d $attachdir && -w $attachdir;
             print "Storing attachment data in local directory $attachdir...\n";
             print "(This may take a very long time)\n";
-            my ($total) = $dbh->selectrow_array("SELECT COUNT(*) FROM attachments");
+            my $ids = $dbh->selectcol_arrayref("SELECT attach_id FROM attachments") || [];
+            my $total = scalar @$ids;
             my $buf = 16;
-            my $sth = $dbh->prepare("SELECT attach_id, thedata FROM attachments ORDER BY attach_id LIMIT ?, ?");
+            my $sth = undef;
+            my $sthbind = 0;
             my ($attachid, $thedata, $hash);
             my $i = 0;
             local $| = 1;
             print "\r$i/$total...";
-            while ($i < $total)
+            while (my @cur = splice @$ids, 0, $buf)
             {
-                $sth->execute($i, $buf);
+                unless ($sth && @cur == $sthbind)
+                {
+                    $sthbind = @cur;
+                    $sth = $dbh->prepare(
+                        "SELECT attach_id, thedata FROM attachments WHERE attach_id IN (" .
+                        join(",", ("?") x $sthbind) . ")"
+                    );
+                }
+                $sth->execute(@cur);
                 last if !$sth->rows;
                 while (($attachid, $thedata) = $sth->fetchrow_array)
                 {