From f5c6e8db1dea90cd2d54bd32a78d89a24d98a3cb Mon Sep 17 00:00:00 2001
From: Marina Glancy <marina@moodle.com>
Date: Fri, 4 Apr 2014 11:37:17 +0800
Subject: [PATCH] MDL-18598 forum: redefine index to allow faster cron jobs

---
 mod/forum/db/install.xml |  6 +++---
 mod/forum/db/upgrade.php | 24 ++++++++++++++++++++++++
 mod/forum/version.php    |  2 +-
 3 files changed, 28 insertions(+), 4 deletions(-)

diff --git a/mod/forum/db/install.xml b/mod/forum/db/install.xml
index 76dcc037896..bc446f10887 100644
--- a/mod/forum/db/install.xml
+++ b/mod/forum/db/install.xml
@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="UTF-8" ?>
-<XMLDB PATH="mod/forum/db" VERSION="20130710" COMMENT="XMLDB file for Moodle mod/forum"
+<XMLDB PATH="mod/forum/db" VERSION="20140404" COMMENT="XMLDB file for Moodle mod/forum"
     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
     xsi:noNamespaceSchemaLocation="../../../lib/xmldb/xmldb.xsd"
 >
@@ -150,7 +150,7 @@
       <INDEXES>
         <INDEX NAME="userid-forumid" UNIQUE="false" FIELDS="userid, forumid"/>
         <INDEX NAME="userid-discussionid" UNIQUE="false" FIELDS="userid, discussionid"/>
-        <INDEX NAME="userid-postid" UNIQUE="false" FIELDS="userid, postid"/>
+        <INDEX NAME="postid-userid" UNIQUE="false" FIELDS="postid, userid"/>
       </INDEXES>
     </TABLE>
     <TABLE NAME="forum_track_prefs" COMMENT="Tracks each users untracked forums">
@@ -167,4 +167,4 @@
       </INDEXES>
     </TABLE>
   </TABLES>
-</XMLDB>
+</XMLDB>
\ No newline at end of file
diff --git a/mod/forum/db/upgrade.php b/mod/forum/db/upgrade.php
index 45f3e754ab5..9fbf31faea5 100644
--- a/mod/forum/db/upgrade.php
+++ b/mod/forum/db/upgrade.php
@@ -112,5 +112,29 @@ function xmldb_forum_upgrade($oldversion) {
     // Moodle v2.6.0 release upgrade line.
     // Put any upgrade step following this.
 
+    if ($oldversion < 2014040400) {
+
+        // Define index userid-postid (not unique) to be dropped form forum_read.
+        $table = new xmldb_table('forum_read');
+        $index = new xmldb_index('userid-postid', XMLDB_INDEX_NOTUNIQUE, array('userid', 'postid'));
+
+        // Conditionally launch drop index userid-postid.
+        if ($dbman->index_exists($table, $index)) {
+            $dbman->drop_index($table, $index);
+        }
+
+
+        // Define index postid-userid (not unique) to be added to forum_read.
+        $index = new xmldb_index('postid-userid', XMLDB_INDEX_NOTUNIQUE, array('postid', 'userid'));
+
+        // Conditionally launch add index postid-userid.
+        if (!$dbman->index_exists($table, $index)) {
+            $dbman->add_index($table, $index);
+        }
+
+        // Forum savepoint reached.
+        upgrade_mod_savepoint(true, 2014040400, 'forum');
+    }
+
     return true;
 }
diff --git a/mod/forum/version.php b/mod/forum/version.php
index 3561dd99c55..1c33e0ef09a 100644
--- a/mod/forum/version.php
+++ b/mod/forum/version.php
@@ -24,7 +24,7 @@
 
 defined('MOODLE_INTERNAL') || die();
 
-$plugin->version   = 2014021700;       // The current module version (Date: YYYYMMDDXX)
+$plugin->version   = 2014040400;       // The current module version (Date: YYYYMMDDXX)
 $plugin->requires  = 2013110500;       // Requires this Moodle version
 $plugin->component = 'mod_forum';      // Full name of the plugin (used for diagnostics)
 $plugin->cron      = 60;