diff --git a/core/modules/node/lib/Drupal/node/NodeFormController.php b/core/modules/node/lib/Drupal/node/NodeFormController.php
index 5145a57..0c909d8 100644
--- a/core/modules/node/lib/Drupal/node/NodeFormController.php
+++ b/core/modules/node/lib/Drupal/node/NodeFormController.php
@@ -318,7 +318,7 @@ protected function actions(array $form, array &$form_state) {
   public function validate(array $form, array &$form_state) {
     $node = $this->buildEntity($form, $form_state);
 
-    if (isset($node->nid) && (node_last_changed($node->nid) > $node->changed)) {
+    if (isset($node->nid) && (node_last_changed($node->nid, $this->getFormLangcode($form_state)) > $node->changed)) {
       form_set_error('changed', t('The content on this page has either been modified by another user, or you have already submitted modifications using this form. As a result, your changes cannot be saved.'));
     }
 
diff --git a/core/modules/node/lib/Drupal/node/Plugin/views/filter/UidRevision.php b/core/modules/node/lib/Drupal/node/Plugin/views/filter/UidRevision.php
index cd00f81..9ca7d89 100644
--- a/core/modules/node/lib/Drupal/node/Plugin/views/filter/UidRevision.php
+++ b/core/modules/node/lib/Drupal/node/Plugin/views/filter/UidRevision.php
@@ -27,7 +27,7 @@ public function query($group_by = FALSE) {
     $args = array_values($this->value);
 
     $this->query->add_where_expression($this->options['group'], "$this->tableAlias.uid IN($placeholder) OR
-      ((SELECT COUNT(*) FROM {node_field_revision} npr WHERE npr.revision_uid IN($placeholder) AND npr.nid = $this->tableAlias.nid) > 0)", array($placeholder => $args),
+      ((SELECT COUNT(DISTINCT vid) FROM {node_field_revision} npr WHERE npr.revision_uid IN($placeholder) AND npr.nid = $this->tableAlias.nid) > 0)", array($placeholder => $args),
       $args);
   }
 
diff --git a/core/modules/node/node.module b/core/modules/node/node.module
index d609cb2..35e5e1a 100644
--- a/core/modules/node/node.module
+++ b/core/modules/node/node.module
@@ -1489,14 +1489,14 @@ function node_user_predelete($account) {
   // Delete nodes (current revisions).
   // @todo Introduce node_mass_delete() or make node_mass_update() more flexible.
   $nodes = db_select('node_field_data', 'n')
-    ->distinct(TRUE)
+    ->distinct()
     ->fields('n', array('nid'))
     ->condition('uid', $account->uid)
     ->execute()
     ->fetchCol();
   node_delete_multiple($nodes);
   // Delete old revisions.
-  $revisions = db_query('SELECT vid FROM {node_field_revision} WHERE uid = :uid', array(':uid' => $account->uid))->fetchCol();
+  $revisions = db_query('SELECT DISTINCT vid FROM {node_field_revision} WHERE uid = :uid', array(':uid' => $account->uid))->fetchCol();
   foreach ($revisions as $revision) {
     node_revision_delete($revision);
   }
@@ -1596,7 +1596,7 @@ function _node_revision_access(EntityInterface $node, $op = 'view', $account = N
     // different revisions so there is no need for a separate database check.
     // Also, if you try to revert to or delete the default revision, that's
     // not good.
-    if ($node->isDefaultRevision() && (db_query('SELECT COUNT(vid) FROM {node_field_revision} WHERE nid = :nid AND default_langcode = 1', array(':nid' => $node->nid))->fetchField() == 1 || $op == 'update' || $op == 'delete')) {
+    if ($node->isDefaultRevision() && (db_query('SELECT COUNT(*) FROM {node_field_revision} WHERE nid = :nid AND default_langcode = 1', array(':nid' => $node->nid))->fetchField() == 1 || $op == 'update' || $op == 'delete')) {
       $access[$cid] = FALSE;
     }
     elseif (user_access('administer nodes', $account)) {
@@ -1842,12 +1842,16 @@ function node_page_title(EntityInterface $node) {
  *
  * @param $nid
  *   The ID of a node.
+ * @param $langcode
+ *   (optional) The language the node has been last modified in. Defaults to the
+ *   node language.
  *
  * @return
  *   A unix timestamp indicating the last time the node was changed.
  */
-function node_last_changed($nid) {
-  return db_query('SELECT changed FROM {node_field_data} WHERE nid = :nid ORDER BY changed DESC LIMIT 1', array(':nid' => $nid))->fetch()->changed;
+function node_last_changed($nid, $langcode = NULL) {
+  $language_clause = isset($langcode) ? 'langcode = :langcode' : 'default_langcode = 1';
+  return db_query('SELECT changed FROM {node_field_data} WHERE nid = :nid AND ' . $language_clause, array(':nid' => $nid, ':langcode' => $langcode))->fetch()->changed;
 }
 
 /**
@@ -1861,14 +1865,7 @@ function node_last_changed($nid) {
  */
 function node_revision_list(EntityInterface $node) {
   $revisions = array();
-  $result = db_query('SELECT nr.vid, nr.title, nr.log, nr.revision_uid AS uid, n.vid AS current_vid, nr.revision_timestamp, u.name ' .
-    'FROM {node_field_revision} nr ' .
-    'LEFT JOIN {node} n ON n.vid = nr.vid ' .
-    'INNER JOIN {users} u ON u.uid = nr.revision_uid ' .
-    'WHERE nr.nid = :nid ' .
-    'ORDER BY nr.vid DESC',
-    array(':nid' => $node->nid)
-  );
+  $result = db_query('SELECT nr.vid, nr.title, nr.log, nr.revision_uid AS uid, n.vid AS current_vid, nr.revision_timestamp, u.name FROM {node_field_revision} nr LEFT JOIN {node} n ON n.vid = nr.vid INNER JOIN {users} u ON u.uid = nr.revision_uid WHERE nr.nid = :nid AND nr.default_langcode = 1 ORDER BY nr.vid DESC', array(':nid' => $node->nid));
   foreach ($result as $revision) {
     $revisions[$revision->vid] = $revision;
   }
@@ -1905,6 +1902,7 @@ function node_get_recent($number = 10) {
     }
   }
   $nids = $query
+    ->distinct()
     ->fields('n', array('nid'))
     ->orderBy('n.changed', 'DESC')
     ->range(0, $number)
@@ -2062,6 +2060,9 @@ function node_block_access($block) {
  *   format_xml_elements(). A list of channel elements can be found at the
  *   @link http://cyber.law.harvard.edu/rss/rss.html RSS 2.0 Specification. @endlink
  *   The link should be an absolute URL.
+ * @param $langcode
+ *   (optional) The language the node has been last modified in. Defaults to the
+ *   node language.
  *
  * @todo Convert taxonomy_term_feed() to a view, so this method is not needed
  *   anymore.
@@ -2078,9 +2079,10 @@ function node_feed($nids = FALSE, $channel = array()) {
 
   if ($nids === FALSE) {
     $nids = db_select('node_field_data', 'n')
-      ->fields('n', array('nid', 'created'))
+      ->fields('n', array('nid'))
       ->condition('n.promote', 1)
       ->condition('n.status', 1)
+      // TODO Should we filter this by language (more performant)?
       ->groupBy('n.nid')
       ->orderBy('n.created', 'DESC')
       ->range(0, $rss_config->get('items.limit'))
diff --git a/core/modules/node/node.pages.inc b/core/modules/node/node.pages.inc
index 30f1162..9aa4982 100644
--- a/core/modules/node/node.pages.inc
+++ b/core/modules/node/node.pages.inc
@@ -379,7 +379,7 @@ function node_revision_delete_confirm_submit($form, &$form_state) {
   watchdog('content', '@type: deleted %title revision %revision.', array('@type' => $node_revision->type, '%title' => $node_revision->label(), '%revision' => $node_revision->vid));
   drupal_set_message(t('Revision from %revision-date of @type %title has been deleted.', array('%revision-date' => format_date($node_revision->revision_timestamp), '@type' => node_get_type_label($node_revision), '%title' => $node_revision->label())));
   $form_state['redirect'] = 'node/' . $node_revision->nid;
-  if (db_query('SELECT COUNT(vid) FROM {node_field_revision} WHERE nid = :nid', array(':nid' => $node_revision->nid))->fetchField() > 1) {
+  if (db_query('SELECT COUNT(DISTINCT vid) FROM {node_field_revision} WHERE nid = :nid', array(':nid' => $node_revision->nid))->fetchField() > 1) {
     $form_state['redirect'] .= '/revisions';
   }
 }