Index: modules/user.module
===================================================================
RCS file: /cvs/drupal/drupal/modules/Attic/user.module,v
retrieving revision 1.612.2.16
diff -u -r1.612.2.16 user.module
--- modules/user.module	2 Aug 2006 18:13:27 -0000	1.612.2.16
+++ modules/user.module	15 Sep 2006 15:18:25 -0000
@@ -56,6 +56,10 @@
       $query[] = "pass = '%s'";
       $params[] = md5($value);
     }
+    else if ($key == 'name' || $key == 'name_lower') {
+      $query[] = "name_lower = LOWER('%s')";
+      $params[] = $value;
+    }
     else {
       $query[]= "LOWER($key) = LOWER('%s')";
       $params[] = $value;
@@ -109,6 +113,10 @@
 
     $data = unserialize(db_result(db_query('SELECT data FROM {users} WHERE uid = %d', $account->uid)));
     foreach ($array as $key => $value) {
+      if ($key == 'name' && !empty($value)) {
+        $query .= "name_lower = LOWER('%s'), ";
+        $v[] = $value;
+      }
       if ($key == 'pass' && !empty($value)) {
         $query .= "$key = '%s', ";
         $v[] = md5($value);
@@ -163,6 +171,19 @@
     // because we don't have a fully initialized user object yet.
     foreach ($array as $key => $value) {
       switch($key) {
+        // We store the name, as entered, in the name column, and the lowercase version of it in name_lower.
+        // This facilitates fast user lookups.
+        case 'name':
+          $fields[] = $key;
+          $values[] = $value;
+          $s[] = "'%s'";
+          $fields[] = 'name_lower';
+          $values[] = $value;
+          $s[] = "LOWER('%s')";
+          break;
+        // name_lower should never be tampered with via parameter to this function.
+        case 'name_lower':
+          break;
         case 'pass':
           $fields[] = $key;
           $values[] = md5($value);
@@ -369,8 +390,8 @@
  * @return boolean true for blocked users, false for active
  */
 function user_is_blocked($name) {
-  $allow = db_fetch_object(db_query("SELECT * FROM {users} WHERE status = 1 AND name = LOWER('%s')", $name));
-  $deny  = db_fetch_object(db_query("SELECT * FROM {users} WHERE status = 0 AND name = LOWER('%s')", $name));
+  $allow = db_fetch_object(db_query("SELECT * FROM {users} WHERE status = 1 AND name_lower = LOWER('%s')", $name));
+  $deny  = db_fetch_object(db_query("SELECT * FROM {users} WHERE status = 0 AND name_lower = LOWER('%s')", $name));
 
   return $deny && !$allow;
 }
@@ -481,7 +502,7 @@
         $find = array();
         // Replace wildcards with MySQL/PostgreSQL wildcards.
         $keys = preg_replace('!\*+!', '%', $keys);
-        $result = pager_query("SELECT * FROM {users} WHERE LOWER(name) LIKE LOWER('%%%s%%')", 15, 0, NULL, $keys);
+        $result = pager_query("SELECT * FROM {users} WHERE name_lower LIKE LOWER('%%%s%%')", 15, 0, NULL, $keys);
         while ($account = db_fetch_object($result)) {
           $find[] = array('title' => $account->name, 'link' => url('user/'. $account->uid));
         }
@@ -1367,7 +1388,7 @@
     if ($error = user_validate_name($edit['name'])) {
       form_set_error('name', $error);
     }
-    else if (db_num_rows(db_query("SELECT uid FROM {users} WHERE uid != %d AND LOWER(name) = LOWER('%s')", $uid, $edit['name'])) > 0) {
+    else if (db_num_rows(db_query("SELECT uid FROM {users} WHERE uid != %d AND name_lower = LOWER('%s')", $uid, $edit['name'])) > 0) {
       form_set_error('name', t('The name %name is already taken.', array('%name' => theme('placeholder', $edit['name']))));
     }
     else if (drupal_is_denied('user', $edit['name'])) {
@@ -2125,7 +2146,7 @@
  */
 function user_autocomplete($string) {
   $matches = array();
-  $result = db_query_range("SELECT name FROM {users} WHERE LOWER(name) LIKE LOWER('%s%%')", $string, 0, 10);
+  $result = db_query_range("SELECT name FROM {users} WHERE name_lower LIKE LOWER('%s%%')", $string, 0, 10);
   while ($user = db_fetch_object($result)) {
     $matches[$user->name] = check_plain($user->name);
   }
Index: database/updates.inc
===================================================================
RCS file: /cvs/drupal/drupal/database/Attic/updates.inc,v
retrieving revision 1.224.2.6
diff -u -r1.224.2.6 updates.inc
--- database/updates.inc	8 Jun 2006 21:25:50 -0000	1.224.2.6
+++ database/updates.inc	15 Sep 2006 15:18:26 -0000
@@ -2013,3 +2013,25 @@
 
   return $ret;
 }
+
+/**
+ * Add name_lower to users for faster lookups
+ */
+function system_update_183() {
+  $ret = array();
+
+  switch ($GLOBALS['db_type']) {
+    case 'mysql':
+    case 'mysqli':
+      $ret[] = update_sql("ALTER TABLE {users} ADD COLUMN name_lower varchar(60) NOT NULL default '' AFTER name");
+      $ret[] = update_sql("UPDATE {users} SET name_lower = LOWER(name)");
+      $ret[] = update_sql('ALTER TABLE {users} ADD  UNIQUE INDEX (name_lower)');
+      break;
+    case 'pgsql':
+      db_add_column($ret, 'users', 'name_lower', 'varchar(60)', array('not null' => TRUE, 'default' => FALSE));
+      $ret[] = update_sql("UPDATE {users} SET name_lower = LOWER(name)");
+      $ret[] = update_sql('CREATE UNIQUE INDEX {users}_name_lower_idx ON {users} (name_lower)');
+      break;
+  }
+  return $ret;
+}