diff --git a/core/modules/comment/comment.install b/core/modules/comment/comment.install
index d641f34..114bef4 100644
--- a/core/modules/comment/comment.install
+++ b/core/modules/comment/comment.install
@@ -566,6 +566,22 @@ function comment_update_8006(&$sandbox) {
   foreach ($node_types as $node_type) {
     // COMMENT_OPEN
     $default_value = variable_get('comment_' . $node_type, 2);
+    // Skip to create field when comments disabled or hidden for the given type
+    // and there's no allowed comments to be posted for.
+    $comments_exists = (bool) db_query_range("SELECT 1 FROM {comment} c WHERE c.entity_type = 'node' AND c.entity_id IN (SELECT nid FROM {node} WHERE type = :type)", 0, 1, array(':type' => $node_type))->fetchField();
+    $commenting_enabled = (bool) db_query_range("SELECT 1 FROM {node} WHERE type = :type and comment = 2", 0, 1, array(':type' => $node_type));
+    if (!($comments_exists || $commenting_enabled || $default_value == 2)) {
+      // Mark deleted all field instances for the comment bundle to cleanup
+      // unused data in database.
+      db_update('field_config_instance')
+        ->fields(array(
+          'deleted' => 1,
+        ))
+        ->condition('entity_type', 'comment')
+        ->condition('bundle', 'comment_node_' . $node_type)
+        ->execute();
+      continue;
+    }
     // Add a default comment field for existing node comments.
     $field = array(
       'cardinality' => '1',
@@ -706,58 +722,67 @@ function comment_update_8007(&$sandbox) {
     ->fetchAllAssoc('nid');
 
   if (count($nodes) > 0) {
-    $insert = db_insert('field_data_comment_node_' . $sandbox['node_type'])
-      ->fields(array(
-        'entity_type',
-        'bundle',
-        'entity_id',
-        'revision_id',
-        'langcode',
-        'delta',
-        'comment_node_' . $sandbox['node_type'] . '_comment',
-      ));
-    $revision = db_insert('field_revision_comment_node_' . $sandbox['node_type'])
-      ->fields(array(
-        'entity_type',
-        'bundle',
-        'entity_id',
-        'revision_id',
-        'langcode',
-        'delta',
-        'comment_node_' . $sandbox['node_type'] . '_comment',
-      ));
-
-    // Update the field name to match the node type.
-    db_update('comment')
-      ->fields(array(
-        'field_name' => 'comment_node_' . $sandbox['node_type'],
-      ))
-      ->condition('entity_id', array_keys($nodes))
-      ->execute();
-    foreach ($nodes as $nid => $node) {
-      $insert->values(array(
-        'entity_type' => 'node',
-        'bundle' => $sandbox['node_type'],
-        'entity_id' => $nid,
-        'revision_id' => $node->vid,
-        'langcode' => $node->langcode,
-        'delta' => 0,
-        'comment_node_' . $sandbox['node_type'] . '_comment' => $node->comment,
-      ));
-      $revision->values(array(
-        'entity_type' => 'node',
-        'bundle' => $sandbox['node_type'],
-        'entity_id' => $nid,
-        'revision_id' => $node->vid,
-        'langcode' => $node->langcode,
-        'delta' => 0,
-        'comment_node_' . $sandbox['node_type'] . '_comment' => $node->comment,
-      ));
-      $sandbox['progress']++;
-      $sandbox['current_nid'] = $nid;
+    // Do not try update data if no comment fields were added.
+    if (db_table_exists('field_data_comment_node_' . $sandbox['node_type'])) {
+      $insert = db_insert('field_data_comment_node_' . $sandbox['node_type'])
+        ->fields(array(
+          'entity_type',
+          'bundle',
+          'entity_id',
+          'revision_id',
+          'langcode',
+          'delta',
+          'comment_node_' . $sandbox['node_type'] . '_comment',
+        ));
+      $revision = db_insert('field_revision_comment_node_' . $sandbox['node_type'])
+        ->fields(array(
+          'entity_type',
+          'bundle',
+          'entity_id',
+          'revision_id',
+          'langcode',
+          'delta',
+          'comment_node_' . $sandbox['node_type'] . '_comment',
+        ));
+
+      // Update the field name to match the node type.
+      db_update('comment')
+        ->fields(array(
+          'field_name' => 'comment_node_' . $sandbox['node_type'],
+        ))
+        ->condition('entity_id', array_keys($nodes))
+        ->execute();
+      foreach ($nodes as $nid => $node) {
+        $insert->values(array(
+          'entity_type' => 'node',
+          'bundle' => $sandbox['node_type'],
+          'entity_id' => $nid,
+          'revision_id' => $node->vid,
+          'langcode' => $node->langcode,
+          'delta' => 0,
+          'comment_node_' . $sandbox['node_type'] . '_comment' => $node->comment,
+        ));
+        $revision->values(array(
+          'entity_type' => 'node',
+          'bundle' => $sandbox['node_type'],
+          'entity_id' => $nid,
+          'revision_id' => $node->vid,
+          'langcode' => $node->langcode,
+          'delta' => 0,
+          'comment_node_' . $sandbox['node_type'] . '_comment' => $node->comment,
+        ));
+        $sandbox['progress']++;
+        $sandbox['current_nid'] = $nid;
+      }
+      $insert->execute();
+      $revision->execute();
+    }
+    else {
+      // Skip the nodes to show progress.
+      $sandbox['progress'] += count($nodes);
+      end($nodes);
+      $sandbox['current_nid'] = key($nodes);
     }
-    $insert->execute();
-    $revision->execute();
   }
   else {
     // Move to the next node type.
diff --git a/core/modules/system/lib/Drupal/system/Tests/Upgrade/CommentUpgradePathTest.php b/core/modules/system/lib/Drupal/system/Tests/Upgrade/CommentUpgradePathTest.php
index 2e8e3c9..3339e52 100644
--- a/core/modules/system/lib/Drupal/system/Tests/Upgrade/CommentUpgradePathTest.php
+++ b/core/modules/system/lib/Drupal/system/Tests/Upgrade/CommentUpgradePathTest.php
@@ -28,6 +28,8 @@ public function setUp() {
       drupal_get_path('module', 'system') . '/tests/upgrade/drupal-7.filled.standard_all.database.php.gz',
       // Language dataset includes nodes with comments so can be reused.
       drupal_get_path('module', 'system') . '/tests/upgrade/drupal-7.language.database.php',
+      // Comment dataset includes comment and variable for poll node type.
+      drupal_get_path('module', 'system') . '/tests/upgrade/drupal-7.comment.database.php',
     );
     parent::setUp();
   }
@@ -40,15 +42,21 @@ public function testCommentUpgrade() {
 
     // Check that comments display on the node.
     $this->drupalGet('node/50');
-    $node = node_load(50);
     $this->assertText('Node title 50', 'Node 50 displayed after update.');
     $this->assertText('First test comment', 'Comment 1 displayed after update.');
     $this->assertText('Reply to first test comment', 'Comment 2 displayed after update.');
 
+    // Check that comment statistics updated properly.
+    $node = node_load(37);
+    debug($node, 'node 37');
+    $node = node_load(50);
+    debug($node, 'node 50');
+
     // Check one instance exists for each node type.
     $types = node_type_get_types();
     foreach (array_keys($types) as $type) {
       $instance = field_info_instance('node', 'comment_node_' . $type, $type);
+      debug($instance, $type);
       $this->assertTrue($instance, format_string('Comment field found for the %type node type', array(
         '%type' => $type
       )));
diff --git a/core/modules/system/tests/upgrade/drupal-7.comment.database.php b/core/modules/system/tests/upgrade/drupal-7.comment.database.php
new file mode 100644
index 0000000..f4d6bff
--- /dev/null
+++ b/core/modules/system/tests/upgrade/drupal-7.comment.database.php
@@ -0,0 +1,281 @@
+<?php
+
+/**
+ * @file
+ * Database additions for comment tests. Used in CommentUpgradePathTest.
+ *
+ * This dump only contains data and schema components relevant for comment
+ * functionality. The drupal-7.filled.standard_all.database.php and
+ * drupal-7.language.database.php files are imported before this dump,
+ * so the tree form the database structure expected in tests altogether.
+ */
+
+// Add comment to the poll node 37.
+db_insert('comment')
+  ->fields(array(
+    'cid',
+    'pid',
+    'nid',
+    'uid',
+    'subject',
+    'hostname',
+    'created',
+    'changed',
+    'status',
+    'thread',
+    'name',
+    'mail',
+    'homepage',
+    'language',
+  ))
+  ->values(array(
+    'cid' => '3',
+    'pid' => '0',
+    'nid' => '37',
+    'uid' => '6',
+    'subject' => 'First test comment',
+    'hostname' => '127.0.0.1',
+    'created' => '1314997642',
+    'changed' => '1314997642',
+    'status' => '1',
+    'thread' => '01/',
+    'name' => 'test user 4',
+    'mail' => '',
+    'homepage' => '',
+    'language' => 'und',
+  ))
+  ->execute();
+
+// Add the comment body.
+db_insert('field_data_comment_body')
+  ->fields(array(
+    'entity_type',
+    'bundle',
+    'deleted',
+    'entity_id',
+    'revision_id',
+    'language',
+    'delta',
+    'comment_body_value',
+    'comment_body_format',
+  ))
+  ->values(array(
+    'entity_type' => 'comment',
+    'bundle' => 'comment_node_poll',
+    'deleted' => '0',
+    'entity_id' => '3',
+    'revision_id' => '3',
+    'language' => 'und',
+    'delta' => '0',
+    'comment_body_value' => 'Poll comment body',
+    'comment_body_format' => 'filtered_html',
+  ))
+  ->execute();
+
+// Add revision for comment body.
+db_insert('field_revision_comment_body')
+  ->fields(array(
+    'entity_type',
+    'bundle',
+    'deleted',
+    'entity_id',
+    'revision_id',
+    'language',
+    'delta',
+    'comment_body_value',
+    'comment_body_format',
+  ))
+  ->values(array(
+    'entity_type' => 'comment',
+    'bundle' => 'comment_node_poll',
+    'deleted' => '0',
+    'entity_id' => '3',
+    'revision_id' => '3',
+    'language' => 'und',
+    'delta' => '0',
+    'comment_body_value' => 'Poll comment body',
+    'comment_body_format' => 'filtered_html',
+  ))
+  ->execute();
+
+// Update comment statistics for node 37.
+db_update('node_comment_statistics')
+  ->fields(array(
+    'cid' => '3',
+    'last_comment_timestamp' => '1314997642',
+    'last_comment_name' => 'test user 4',
+    'last_comment_uid' => '6',
+    'comment_count' => '1',
+  ))
+  ->condition('nid', '37')
+  ->execute();
+
+// Update comment statistics for node 50.
+db_update('node_comment_statistics')
+  ->fields(array(
+    'cid' => '2',
+    'last_comment_timestamp' => '1314997642',
+    'last_comment_name' => 'test user 4',
+    'last_comment_uid' => '6',
+    'comment_count' => '2',
+  ))
+  ->condition('nid', '50')
+  ->execute();
+
+// Add book node.
+db_insert('node')
+  ->fields(array(
+    'nid',
+    'vid',
+    'type',
+    'language',
+    'title',
+    'uid',
+    'status',
+    'created',
+    'changed',
+    'comment',
+    'promote',
+    'sticky',
+    'tnid',
+    'translate',
+  ))
+  ->values(array(
+    'nid' => '54',
+    'vid' => '90',
+    'type' => 'book',
+    'language' => 'und',
+    'title' => 'Node title 54',
+    'uid' => '6',
+    'status' => '1',
+    'created' => '1263769200',
+    'changed' => '1314997642',
+    'comment' => '2',
+    'promote' => '0',
+    'sticky' => '0',
+    'tnid' => '0',
+    'translate' => '0',
+  ))
+  ->execute();
+
+// Add node revision information.
+db_insert('node_revision')
+  ->fields(array(
+    'nid',
+    'vid',
+    'uid',
+    'title',
+    'log',
+    'timestamp',
+    'status',
+    'comment',
+    'promote',
+    'sticky',
+  ))
+  ->values(array(
+    'nid' => '54',
+    'vid' => '90',
+    'uid' => '6',
+    'title' => 'Node title 54',
+    'log' => 'Added a LANGUAGE_NOT_SPECIFIED node to comment on.',
+    'timestamp' => '1314997642',
+    'status' => '1',
+    'comment' => '2',
+    'promote' => '0',
+    'sticky' => '0',
+  ))
+  ->execute();
+
+// Add the body field value.
+db_insert('field_data_body')
+  ->fields(array(
+    'entity_type',
+    'bundle',
+    'deleted',
+    'entity_id',
+    'revision_id',
+    'language',
+    'delta',
+    'body_value',
+    'body_summary',
+    'body_format',
+  ))
+  ->values(array(
+    'entity_type' => 'node',
+    'bundle' => 'book',
+    'deleted' => '0',
+    'entity_id' => '54',
+    'revision_id' => '90',
+    'language' => 'und',
+    'delta' => '0',
+    'body_value' => 'Node body',
+    'body_summary' => 'Node body',
+    'body_format' => 'filtered_html',
+  ))
+  ->execute();
+
+// Add revision information for the body field value.
+db_insert('field_revision_body')
+  ->fields(array(
+    'entity_type',
+    'bundle',
+    'deleted',
+    'entity_id',
+    'revision_id',
+    'language',
+    'delta',
+    'body_value',
+    'body_summary',
+    'body_format',
+  ))
+  ->values(array(
+    'entity_type' => 'node',
+    'bundle' => 'book',
+    'deleted' => '0',
+    'entity_id' => '54',
+    'revision_id' => '90',
+    'language' => 'und',
+    'delta' => '0',
+    'body_value' => 'Node body',
+    'body_summary' => 'Node body',
+    'body_format' => 'filtered_html',
+  ))
+  ->execute();
+
+
+// Add node comment statistics for the book node.
+db_insert('node_comment_statistics')
+  ->fields(array(
+    'nid',
+    'cid',
+    'last_comment_timestamp',
+    'last_comment_name',
+    'last_comment_uid',
+    'comment_count',
+  ))
+  ->values(array(
+    'nid' => '54',
+    'cid' => '0',
+    'last_comment_timestamp' => '1314997642',
+    'last_comment_name' => NULL,
+    'last_comment_uid' => '6',
+    'comment_count' => '0',
+  ))
+  ->execute();
+
+
+// Disable commenting on poll and book node types.
+db_insert('variable')
+  ->fields(array(
+    'name',
+    'value',
+  ))
+  ->values(array(
+    'name' => 'comment_poll',
+    'value' => 'i:1;',
+  ))
+  ->values(array(
+    'name' => 'comment_book',
+    'value' => 'i:1;',
+  ))
+  ->execute();