MDL-4667, MDL-4112 switching order of columns in course-userid log table index in order to please mysql

lib/db/upgrade.php

@@ -2820,6 +2820,33 @@ function xmldb_main_upgrade($oldversion=0) {
         upgrade_main_savepoint($result, 2007101508.02);
     }
 
+    if ($result && $oldversion < 2007101508.03) {
+
+    /// Define index course-userid (not unique) to be dropped form log
+        $table = new XMLDBTable('log');
+        $index = new XMLDBIndex('course-userid');
+        $index->setAttributes(XMLDB_INDEX_NOTUNIQUE, array('course', 'userid'));
+
+    /// Launch drop index course-userid
+        if (index_exists($table, $index)) {
+            $result = $result && drop_index($table, $index);
+        }
+
+    /// Define index userid-course (not unique) to be added to log
+        $table = new XMLDBTable('log');
+        $index = new XMLDBIndex('userid-course');
+        $index->setAttributes(XMLDB_INDEX_NOTUNIQUE, array('userid', 'course'));
+
+    /// Launch add index userid-course
+        if (!index_exists($table, $index)) {
+            $result = $result && add_index($table, $index);
+        }
+
+    /// Main savepoint reached
+        upgrade_main_savepoint($result, 2007101508.03);
+    }
+
+
     return $result;
 }
 

version.php

@@ -6,7 +6,7 @@
 // This is compared against the values stored in the database to determine
 // whether upgrades should be performed (see lib/db/*.php)
 
-    $version = 2007101508.02;  // YYYYMMDD   = date of the 1.9 branch (don't change)
+    $version = 2007101508.03;  // YYYYMMDD   = date of the 1.9 branch (don't change)
                             //         X  = release number 1.9.[0,1,2,3...]
                             //          Y = micro-increments between releases