From c8ade8cbdc1496d015e9030c8790c3c249958ade Mon Sep 17 00:00:00 2001
From: David Curry <david.curry@totaralms.com>
Date: Tue, 28 Jan 2014 11:56:37 +1300
Subject: [PATCH] MDL-43797 lib/db/upgrade.php: Optimise sql for my_pages
 deletion

Change-Id: Idf300ab07afda3bcefea80e617549f40c710e529
---
 lib/db/upgrade.php | 13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/lib/db/upgrade.php b/lib/db/upgrade.php
index d482127cf40..490c82516c0 100644
--- a/lib/db/upgrade.php
+++ b/lib/db/upgrade.php
@@ -2929,12 +2929,13 @@ function xmldb_main_upgrade($oldversion) {
 
     if ($oldversion < 2014012300.01) {
         // Remove deleted users home pages.
-        $active = $DB->get_fieldset_select('user', 'id', 'deleted = ?', array(0));
-        list($insql, $params) = $DB->get_in_or_equal($active, SQL_PARAMS_QM, 'param', false);
-        $sql = 'DELETE FROM {my_pages}
-                WHERE userid ' . $insql;
-
-        $DB->execute($sql, $params);
+        $sql = "DELETE FROM {my_pages}
+                WHERE EXISTS (SELECT {user}.id
+                                  FROM {user}
+                                  WHERE {user}.id = {my_pages}.userid
+                                  AND {user}.deleted = 1)
+                AND {my_pages}.private = 1";
+        $DB->execute($sql);
 
         // Reached main savepoint.
         upgrade_main_savepoint(true, 2014012300.01);