Index: lib/dmllib.php
===================================================================
RCS file: /cvsroot/moodle/moodle/lib/dmllib.php,v
retrieving revision 1.53
diff -u -r1.53 dmllib.php
--- lib/dmllib.php	23 Oct 2006 17:46:08 -0000	1.53
+++ lib/dmllib.php	24 Oct 2006 10:44:08 -0000
@@ -354,6 +354,11 @@
 
 /// GENERIC FUNCTIONS TO GET, INSERT, OR UPDATE DATA  ///////////////////////////////////
 
+// This cache (enabled by setting $CFG['cachegetrecord']) stores the results of 
+// get_record calls within a request, where all fields of a record were requested and 
+// the only condition was id=something. 
+$recordcache=array();
+
 /**
  * Get a single record as an object
  *
@@ -368,12 +373,36 @@
  * @return mixed a fieldset object containing the first mathcing record, or false if none found.
  */
 function get_record($table, $field1, $value1, $field2='', $value2='', $field3='', $value3='', $fields='*') {
-
-    global $CFG;
-
+    
+    global $CFG,$recordcache;
+    
+    // Check to see whether this record is eligible for caching (fields=*, only condition is id)
+    // and cache is turned on
+    $docache=false;
+    if(!empty($CFG->cachegetrecord) && $field1=='id' && !$field2 && !$field3 && $fields=='*') {
+        $docache=true;
+        // If it's in the cache, return it
+        if(array_key_exists($table,$recordcache)) {
+            if(array_key_exists($value1,$recordcache[$table])) {
+                return $recordcache[$table][$value1];
+            }
+        }   
+    }
+    
     $select = where_clause($field1, $value1, $field2, $value2, $field3, $value3);
 
-    return get_record_sql('SELECT '.$fields.' FROM '. $CFG->prefix . $table .' '. $select);
+    $record=get_record_sql('SELECT '.$fields.' FROM '. $CFG->prefix . $table .' '. $select);
+    
+    // If we're caching records, store this one (supposing we got something - we don't cache
+    // failures)
+    if($record && $docache) {
+        if(!array_key_exists($table,$recordcache)) {
+            $recordcache[$table]=array();
+        }
+        $recordcache[$table][$value1]=$record;
+    }
+
+    return $record;
 }
 
 /**
@@ -1022,6 +1051,10 @@
         }
     }
 
+    // Clear entire record cache for table (could be improved to check for ID limitation) 
+    global $recordcache;
+    unset($recordcache[$table]);
+
 /// Arriving here, standard update 
     return $db->Execute('UPDATE '. $CFG->prefix . $table .' SET '. $newfield  .' = \''. $newvalue .'\' '. $select);
 }
@@ -1276,6 +1309,10 @@
         return false;
     }
 
+    // Remove this record from record cache since it will change
+    global $recordcache;
+    unset($recordcache[$table][$dataobject->id]);
+
 /// Temporary hack as part of phasing out all access to obsolete user tables  XXX
     if (!empty($CFG->rolesactive)) {
         if (in_array($table, array('user_students', 'user_teachers', 'user_coursecreators', 'user_admins'))) {