diff --git a/core/app/Upgrade.php b/core/app/Upgrade.php
index df9edc7a..638a1caf 100644
--- a/core/app/Upgrade.php
+++ b/core/app/Upgrade.php
@@ -95,3 +95,12 @@ function upgrade_step_3()
 {
 	return wedb::drop_table('{db_prefix}log_boards');
 }
+
+// 1.0-alpha-1, July 2014. Adding index to sessions to prevent a possible slow query.
+function upgrade_step_4()
+{
+	$request = wesql::query('
+	ALTER TABLE
+		{db_prefix}sessions
+	ADD KEY last_update (last_update)');
+}
\ No newline at end of file
diff --git a/index.php b/index.php
index 9f05bba1..d8fed189 100644
--- a/index.php
+++ b/index.php
@@ -12,7 +12,7 @@
 	return;
 
 define('WEDGE_VERSION', '1.0-beta');
-define('WEDGE', 3); // Internal snapshot number.
+define('WEDGE', 4); // Internal snapshot number.
 
 // Get everything started up...
 if (version_compare(PHP_VERSION, '5.3') < 0)
diff --git a/install/install.sql b/install/install.sql
index ac280f47..236033ac 100644
--- a/install/install.sql
+++ b/install/install.sql
@@ -2068,7 +2068,8 @@ CREATE TABLE {$db_prefix}sessions (
 	session_id char(32) NOT NULL,
 	last_update int(10) unsigned NOT NULL,
 	data text NOT NULL,
-	PRIMARY KEY (session_id)
+	PRIMARY KEY (session_id),
+	KEY last_update (last_update)
 ) ENGINE=MyISAM;
 
 #