=== modified file 'modules/block/block.module'
--- modules/block/block.module	2007-09-27 16:52:00 +0000
+++ modules/block/block.module	2007-10-02 13:35:24 +0000
@@ -220,7 +220,7 @@ function _block_rehash() {
     $old_blocks[$old_block->module][$old_block->delta] = $old_block;
   }
 
-  $blocks = array();
+  $bids = array();
 
   foreach (module_list() as $module) {
     $module_blocks = module_invoke($module, 'block', 'list');
@@ -232,43 +232,20 @@ function _block_rehash() {
         $block['cache'] = isset($block['cache']) ? $block['cache'] : BLOCK_CACHE_PER_ROLE;
         // If previously written to database, load values.
         if (!empty($old_blocks[$module][$delta])) {
-          $block['status'] = $old_blocks[$module][$delta]->status;
-          $block['weight'] = $old_blocks[$module][$delta]->weight;
-          $block['region'] = $old_blocks[$module][$delta]->region;
-          $block['visibility'] = $old_blocks[$module][$delta]->visibility;
-          $block['pages'] = $old_blocks[$module][$delta]->pages;
-          $block['custom'] = $old_blocks[$module][$delta]->custom;
-          $block['throttle'] = $old_blocks[$module][$delta]->throttle;
-          $block['title'] = $old_blocks[$module][$delta]->title;
+          $bids[] = $old_blocks[$module][$delta]->bid;
         }
         // Otherwise, use any set values, or else substitute defaults.
         else {
-          $properties = array('status' => 0, 'weight' => 0, 'region' => 'left', 'pages' => '', 'custom' => 0, 'title' => '');
-          foreach ($properties as $property => $default) {
-            if (!isset($block[$property])) {
-              $block[$property] = $default;
-            }
-          }
+          $block += array('status' => 0, 'weight' => 0, 'region' => 'left', 'pages' => '', 'custom' => 0, 'title' => '', 'visibility' => 0, 'throttle' => 0);
+          db_query("INSERT INTO {blocks} (module, delta, theme, status, weight, region, visibility, pages, custom, throttle, title, cache) VALUES ('%s', '%s', '%s', %d, %d, '%s', %d, '%s', %d, %d, '%s', %d)", $block['module'], $block['delta'], $theme_key, $block['status'], $block['weight'], $block['region'], $block['visibility'], $block['pages'], $block['custom'], $block['throttle'], $block['title'], $block['cache']);
+          $bids[] = db_last_insert_id('blocks', 'bid');
         }
-
-        $blocks[] = $block;
       }
     }
   }
-
-  db_lock_table('blocks');
-  // Remove all blocks from table.
-  db_query("DELETE FROM {blocks} WHERE theme = '%s'", $theme_key);
-
-  // Reinsert new set of blocks into table.
-  foreach ($blocks as $block) {
-    $block += array(
-      'visibility' => NULL,
-      'throttle' => NULL,
-    );
-    db_query("INSERT INTO {blocks} (module, delta, theme, status, weight, region, visibility, pages, custom, throttle, title, cache) VALUES ('%s', '%s', '%s', %d, %d, '%s', %d, '%s', %d, %d, '%s', %d)", $block['module'], $block['delta'], $theme_key, $block['status'], $block['weight'], $block['region'], $block['visibility'], $block['pages'], $block['custom'], $block['throttle'], $block['title'], $block['cache']);
-  }
-  db_unlock_tables();
+  $args = $bids;
+  array_unshift($args, $theme_key);
+  db_query("DELETE FROM {blocks} WHERE theme = '%s' AND bid NOT IN (". db_placeholders($bids) .')', $args);
 
   return $blocks;
 }