Merge branch 'master' into fix/gb/improve-updating-column-in-batches-helper

* master: (56 commits)
  File view buttons
  Don't reset the session when the example failed, because we need capybara-screenshot to have access to it
  Resolve "MR comment + system note highlight don't have the same width"
  Add feature spec for dashboard state filter tabs
  Wording of Mysql support.
  a new feature checklist and more elaborate documentation requirements
  Filter archived project in API v3 only if param present
  Revert to using links instead of buttons in Issuable Index tabs.
  Do not run the codeclimate job on docs-only changes
  Only show gray footer space if environment actions exist
  Migrate Gitlab::Git::Blob.find to Gitaly
  Backport filtered search lazy token consistent state fix
  Add a comment explaining how the branch clean up happens
  Fix Github::Representation::PullRequest#source_branch_exists?
  Add CHANGELOG
  Fix GitHub importer performance on branch existence check
  Rebuild the dynamic path before validating it
  Rename stage ref migration specs to match a class name
  Enable Style/DotPosition Rubocop :cop:
  Revert "Merge branch 'winh-merge-request-related-issues' into 'master'"
  ...

Conflicts:
	db/post_migrate/20170526185921_migrate_build_stage_reference.rb

21 files changed, 174 insertions, 106 deletions

diff --git a/db/migrate/20161124141322_migrate_process_commit_worker_jobs.rb b/db/migrate/20161124141322_migrate_process_commit_worker_jobs.rb
index e5292cfba07..c0cb9d78748 100644
--- a/db/migrate/20161124141322_migrate_process_commit_worker_jobs.rb
+++ b/db/migrate/20161124141322_migrate_process_commit_worker_jobs.rb
@@ -6,9 +6,9 @@ class MigrateProcessCommitWorkerJobs < ActiveRecord::Migration
 
   class Project < ActiveRecord::Base
     def self.find_including_path(id)
-      select("projects.*, CONCAT(namespaces.path, '/', projects.path) AS path_with_namespace").
-        joins('INNER JOIN namespaces ON namespaces.id = projects.namespace_id').
-        find_by(id: id)
+      select("projects.*, CONCAT(namespaces.path, '/', projects.path) AS path_with_namespace")
+        .joins('INNER JOIN namespaces ON namespaces.id = projects.namespace_id')
+        .find_by(id: id)
     end
 
     def repository_storage_path
diff --git a/db/migrate/20161207231620_fixup_environment_name_uniqueness.rb b/db/migrate/20161207231620_fixup_environment_name_uniqueness.rb
index a20a903a752..f73e4f6c99b 100644
--- a/db/migrate/20161207231620_fixup_environment_name_uniqueness.rb
+++ b/db/migrate/20161207231620_fixup_environment_name_uniqueness.rb
@@ -8,11 +8,11 @@ class FixupEnvironmentNameUniqueness < ActiveRecord::Migration
     environments = Arel::Table.new(:environments)
 
     # Get all [project_id, name] pairs that occur more than once
-    finder_sql = environments.
-      group(environments[:project_id], environments[:name]).
-      having(Arel.sql("COUNT(1)").gt(1)).
-      project(environments[:project_id], environments[:name]).
-      to_sql
+    finder_sql = environments
+      .group(environments[:project_id], environments[:name])
+      .having(Arel.sql("COUNT(1)").gt(1))
+      .project(environments[:project_id], environments[:name])
+      .to_sql
 
     conflicting = connection.exec_query(finder_sql)
 
@@ -28,12 +28,12 @@ class FixupEnvironmentNameUniqueness < ActiveRecord::Migration
   # Rename conflicting environments by appending "-#{id}" to all but the first
   def fix_duplicates(project_id, name)
     environments = Arel::Table.new(:environments)
-    finder_sql = environments.
-      where(environments[:project_id].eq(project_id)).
-      where(environments[:name].eq(name)).
-      order(environments[:id].asc).
-      project(environments[:id], environments[:name]).
-      to_sql
+    finder_sql = environments
+      .where(environments[:project_id].eq(project_id))
+      .where(environments[:name].eq(name))
+      .order(environments[:id].asc)
+      .project(environments[:id], environments[:name])
+      .to_sql
 
     # Now we have the data for all the conflicting rows
     conflicts = connection.exec_query(finder_sql).rows
@@ -41,11 +41,11 @@ class FixupEnvironmentNameUniqueness < ActiveRecord::Migration
 
     conflicts.each do |id, name|
       update_sql =
-        Arel::UpdateManager.new(ActiveRecord::Base).
-          table(environments).
-          set(environments[:name] => name + "-" + id.to_s).
-          where(environments[:id].eq(id)).
-          to_sql
+        Arel::UpdateManager.new(ActiveRecord::Base)
+          .table(environments)
+          .set(environments[:name] => name + "-" + id.to_s)
+          .where(environments[:id].eq(id))
+          .to_sql
 
       connection.exec_update(update_sql, self.class.name, [])
     end
diff --git a/db/migrate/20161207231626_add_environment_slug.rb b/db/migrate/20161207231626_add_environment_slug.rb
index 8e98ee5b9ba..83cdd484c4c 100644
--- a/db/migrate/20161207231626_add_environment_slug.rb
+++ b/db/migrate/20161207231626_add_environment_slug.rb
@@ -19,10 +19,10 @@ class AddEnvironmentSlug < ActiveRecord::Migration
     finder = environments.project(:id, :name)
 
     connection.exec_query(finder.to_sql).rows.each do |id, name|
-      updater = Arel::UpdateManager.new(ActiveRecord::Base).
-        table(environments).
-        set(environments[:slug] => generate_slug(name)).
-        where(environments[:id].eq(id))
+      updater = Arel::UpdateManager.new(ActiveRecord::Base)
+        .table(environments)
+        .set(environments[:slug] => generate_slug(name))
+        .where(environments[:id].eq(id))
 
       connection.exec_update(updater.to_sql, self.class.name, [])
     end
diff --git a/db/migrate/20170316163800_rename_system_namespaces.rb b/db/migrate/20170316163800_rename_system_namespaces.rb
index b5408fbf112..9e9fb5ac225 100644
--- a/db/migrate/20170316163800_rename_system_namespaces.rb
+++ b/db/migrate/20170316163800_rename_system_namespaces.rb
@@ -159,9 +159,9 @@ class RenameSystemNamespaces < ActiveRecord::Migration
   end
 
   def system_namespace
-    @system_namespace ||= Namespace.where(parent_id: nil).
-                            where(arel_table[:path].matches(system_namespace_path)).
-                            first
+    @system_namespace ||= Namespace.where(parent_id: nil)
+                            .where(arel_table[:path].matches(system_namespace_path))
+                            .first
   end
 
   def system_namespace_path
@@ -209,8 +209,8 @@ class RenameSystemNamespaces < ActiveRecord::Migration
   end
 
   def repo_paths_for_namespace(namespace)
-    projects_for_namespace(namespace).distinct.
-      select(:repository_storage).map(&:repository_storage_path)
+    projects_for_namespace(namespace).distinct
+      .select(:repository_storage).map(&:repository_storage_path)
   end
 
   def uploads_dir
diff --git a/db/migrate/20170503140202_turn_nested_groups_into_regular_groups_for_mysql.rb b/db/migrate/20170503140202_turn_nested_groups_into_regular_groups_for_mysql.rb
index c67690642c9..33908ae1156 100644
--- a/db/migrate/20170503140202_turn_nested_groups_into_regular_groups_for_mysql.rb
+++ b/db/migrate/20170503140202_turn_nested_groups_into_regular_groups_for_mysql.rb
@@ -87,8 +87,8 @@ class TurnNestedGroupsIntoRegularGroupsForMysql < ActiveRecord::Migration
     while current&.parent_id
       # We're using find_by(id: ...) here to deal with cases where the
       # parent_id may point to a missing row.
-      current = Namespace.unscoped.select([:id, :parent_id]).
-        find_by(id: current.parent_id)
+      current = Namespace.unscoped.select([:id, :parent_id])
+        .find_by(id: current.parent_id)
 
       ancestors << current.id if current
     end
@@ -99,11 +99,11 @@ class TurnNestedGroupsIntoRegularGroupsForMysql < ActiveRecord::Migration
   # Returns a relation containing all the members that have access to any of
   # the current namespace's parent namespaces.
   def all_members_for(namespace)
-    Member.
-      unscoped.
-      select(['user_id', 'MAX(access_level) AS access_level']).
-      where(source_type: 'Namespace', source_id: ancestors_for(namespace)).
-      group(:user_id)
+    Member
+      .unscoped
+      .select(['user_id', 'MAX(access_level) AS access_level'])
+      .where(source_type: 'Namespace', source_id: ancestors_for(namespace))
+      .group(:user_id)
   end
 
   def bulk_insert_members(rows)
diff --git a/db/migrate/20170526185602_add_stage_id_to_ci_builds.rb b/db/migrate/20170526185602_add_stage_id_to_ci_builds.rb
index d5675d5828b..d27cba76d81 100644
--- a/db/migrate/20170526185602_add_stage_id_to_ci_builds.rb
+++ b/db/migrate/20170526185602_add_stage_id_to_ci_builds.rb
@@ -3,19 +3,11 @@ class AddStageIdToCiBuilds < ActiveRecord::Migration
 
   DOWNTIME = false
 
-  disable_ddl_transaction!
-
   def up
     add_column :ci_builds, :stage_id, :integer
-
-    add_concurrent_foreign_key :ci_builds, :ci_stages, column: :stage_id, on_delete: :cascade
-    add_concurrent_index :ci_builds, :stage_id
   end
 
   def down
-    remove_foreign_key :ci_builds, column: :stage_id
-    remove_concurrent_index :ci_builds, :stage_id
-
     remove_column :ci_builds, :stage_id, :integer
   end
 end
diff --git a/db/migrate/20170619144837_add_index_for_head_pipeline_merge_request.rb b/db/migrate/20170619144837_add_index_for_head_pipeline_merge_request.rb
new file mode 100644
index 00000000000..02863bee082
--- /dev/null
+++ b/db/migrate/20170619144837_add_index_for_head_pipeline_merge_request.rb
@@ -0,0 +1,15 @@
+class AddIndexForHeadPipelineMergeRequest < ActiveRecord::Migration
+  include Gitlab::Database::MigrationHelpers
+
+  DOWNTIME = false
+
+  disable_ddl_transaction!
+
+  def up
+    add_concurrent_index :merge_requests, :head_pipeline_id
+  end
+
+  def down
+    remove_concurrent_index :merge_requests, :head_pipeline_id if index_exists?(:merge_requests, :head_pipeline_id)
+  end
+end
diff --git a/db/post_migrate/20161109150329_fix_project_records_with_invalid_visibility.rb b/db/post_migrate/20161109150329_fix_project_records_with_invalid_visibility.rb
index 14b5ef476f0..69007b8e8ed 100644
--- a/db/post_migrate/20161109150329_fix_project_records_with_invalid_visibility.rb
+++ b/db/post_migrate/20161109150329_fix_project_records_with_invalid_visibility.rb
@@ -13,13 +13,13 @@ class FixProjectRecordsWithInvalidVisibility < ActiveRecord::Migration
     namespaces = Arel::Table.new(:namespaces)
 
     finder_sql =
-      projects.
-        join(namespaces, Arel::Nodes::InnerJoin).
-        on(projects[:namespace_id].eq(namespaces[:id])).
-        where(projects[:visibility_level].gt(namespaces[:visibility_level])).
-        project(projects[:id], namespaces[:visibility_level]).
-        take(BATCH_SIZE).
-        to_sql
+      projects
+        .join(namespaces, Arel::Nodes::InnerJoin)
+        .on(projects[:namespace_id].eq(namespaces[:id]))
+        .where(projects[:visibility_level].gt(namespaces[:visibility_level]))
+        .project(projects[:id], namespaces[:visibility_level])
+        .take(BATCH_SIZE)
+        .to_sql
 
     # Update matching rows in batches. Each batch can cause up to 3 UPDATE
     # statements, in addition to the SELECT: one per visibility_level
@@ -33,10 +33,10 @@ class FixProjectRecordsWithInvalidVisibility < ActiveRecord::Migration
       end
 
       updates.each do |visibility_level, project_ids|
-        updater = Arel::UpdateManager.new(ActiveRecord::Base).
-          table(projects).
-          set(projects[:visibility_level] => visibility_level).
-          where(projects[:id].in(project_ids))
+        updater = Arel::UpdateManager.new(ActiveRecord::Base)
+          .table(projects)
+          .set(projects[:visibility_level] => visibility_level)
+          .where(projects[:id].in(project_ids))
 
         ActiveRecord::Base.connection.exec_update(updater.to_sql, self.class.name, [])
       end
diff --git a/db/post_migrate/20161221153951_rename_reserved_project_names.rb b/db/post_migrate/20161221153951_rename_reserved_project_names.rb
index 49a6bc884a8..d322844e2fd 100644
--- a/db/post_migrate/20161221153951_rename_reserved_project_names.rb
+++ b/db/post_migrate/20161221153951_rename_reserved_project_names.rb
@@ -79,17 +79,17 @@ class RenameReservedProjectNames < ActiveRecord::Migration
   private
 
   def reserved_projects
-    Project.unscoped.
-      includes(:namespace).
-      where('EXISTS (SELECT 1 FROM namespaces WHERE projects.namespace_id = namespaces.id)').
-      where('projects.path' => KNOWN_PATHS)
+    Project.unscoped
+      .includes(:namespace)
+      .where('EXISTS (SELECT 1 FROM namespaces WHERE projects.namespace_id = namespaces.id)')
+      .where('projects.path' => KNOWN_PATHS)
   end
 
   def route_exists?(full_path)
     quoted_path = ActiveRecord::Base.connection.quote_string(full_path)
 
-    ActiveRecord::Base.connection.
-      select_all("SELECT id, path FROM routes WHERE path = '#{quoted_path}'").present?
+    ActiveRecord::Base.connection
+      .select_all("SELECT id, path FROM routes WHERE path = '#{quoted_path}'").present?
   end
 
   # Adds number to the end of the path that is not taken by other route
diff --git a/db/post_migrate/20170104150317_requeue_pending_delete_projects.rb b/db/post_migrate/20170104150317_requeue_pending_delete_projects.rb
index f399950bd5e..d7be004d47f 100644
--- a/db/post_migrate/20170104150317_requeue_pending_delete_projects.rb
+++ b/db/post_migrate/20170104150317_requeue_pending_delete_projects.rb
@@ -39,11 +39,11 @@ class RequeuePendingDeleteProjects < ActiveRecord::Migration
 
   def find_batch
     projects = Arel::Table.new(:projects)
-    projects.project(projects[:id]).
-      where(projects[:pending_delete].eq(true)).
-      where(projects[:namespace_id].not_eq(nil)).
-      skip(@offset * BATCH_SIZE).
-      take(BATCH_SIZE).
-      to_sql
+    projects.project(projects[:id])
+      .where(projects[:pending_delete].eq(true))
+      .where(projects[:namespace_id].not_eq(nil))
+      .skip(@offset * BATCH_SIZE)
+      .take(BATCH_SIZE)
+      .to_sql
   end
 end
diff --git a/db/post_migrate/20170106142508_fill_authorized_projects.rb b/db/post_migrate/20170106142508_fill_authorized_projects.rb
index 314c8440c8b..0ca20587981 100644
--- a/db/post_migrate/20170106142508_fill_authorized_projects.rb
+++ b/db/post_migrate/20170106142508_fill_authorized_projects.rb
@@ -15,8 +15,8 @@ class FillAuthorizedProjects < ActiveRecord::Migration
   disable_ddl_transaction!
 
   def up
-    relation = User.select(:id).
-      where('authorized_projects_populated IS NOT TRUE')
+    relation = User.select(:id)
+      .where('authorized_projects_populated IS NOT TRUE')
 
     relation.find_in_batches(batch_size: 1_000) do |rows|
       args = rows.map { |row| [row.id] }
diff --git a/db/post_migrate/20170313133418_rename_more_reserved_project_names.rb b/db/post_migrate/20170313133418_rename_more_reserved_project_names.rb
index 44c688fa134..6a49450cc50 100644
--- a/db/post_migrate/20170313133418_rename_more_reserved_project_names.rb
+++ b/db/post_migrate/20170313133418_rename_more_reserved_project_names.rb
@@ -21,17 +21,17 @@ class RenameMoreReservedProjectNames < ActiveRecord::Migration
   private
 
   def reserved_projects
-    Project.unscoped.
-      includes(:namespace).
-      where('EXISTS (SELECT 1 FROM namespaces WHERE projects.namespace_id = namespaces.id)').
-      where('projects.path' => KNOWN_PATHS)
+    Project.unscoped
+      .includes(:namespace)
+      .where('EXISTS (SELECT 1 FROM namespaces WHERE projects.namespace_id = namespaces.id)')
+      .where('projects.path' => KNOWN_PATHS)
   end
 
   def route_exists?(full_path)
     quoted_path = ActiveRecord::Base.connection.quote_string(full_path)
 
-    ActiveRecord::Base.connection.
-      select_all("SELECT id, path FROM routes WHERE path = '#{quoted_path}'").present?
+    ActiveRecord::Base.connection
+      .select_all("SELECT id, path FROM routes WHERE path = '#{quoted_path}'").present?
   end
 
   # Adds number to the end of the path that is not taken by other route
diff --git a/db/post_migrate/20170324160416_migrate_user_activities_to_users_last_activity_on.rb b/db/post_migrate/20170324160416_migrate_user_activities_to_users_last_activity_on.rb
index 9ad36482c8a..397a9a2d28e 100644
--- a/db/post_migrate/20170324160416_migrate_user_activities_to_users_last_activity_on.rb
+++ b/db/post_migrate/20170324160416_migrate_user_activities_to_users_last_activity_on.rb
@@ -38,11 +38,11 @@ class MigrateUserActivitiesToUsersLastActivityOn < ActiveRecord::Migration
     activities = activities(day.at_beginning_of_day, day.at_end_of_day, page: page)
 
     update_sql =
-      Arel::UpdateManager.new(ActiveRecord::Base).
-        table(users_table).
-        set(users_table[:last_activity_on] => day.to_date).
-        where(users_table[:username].in(activities.map(&:first))).
-        to_sql
+      Arel::UpdateManager.new(ActiveRecord::Base)
+        .table(users_table)
+        .set(users_table[:last_activity_on] => day.to_date)
+        .where(users_table[:username].in(activities.map(&:first)))
+        .to_sql
 
     connection.exec_update(update_sql, self.class.name, [])
 
diff --git a/db/post_migrate/20170502070007_enable_auto_cancel_pending_pipelines_for_all.rb b/db/post_migrate/20170502070007_enable_auto_cancel_pending_pipelines_for_all.rb
index 3c13a3d2518..765daa0a347 100644
--- a/db/post_migrate/20170502070007_enable_auto_cancel_pending_pipelines_for_all.rb
+++ b/db/post_migrate/20170502070007_enable_auto_cancel_pending_pipelines_for_all.rb
@@ -7,6 +7,8 @@ class EnableAutoCancelPendingPipelinesForAll < ActiveRecord::Migration
   DOWNTIME = false
 
   def up
+    disable_statement_timeout
+
     update_column_in_batches(:projects, :auto_cancel_pending_pipelines, 1)
   end
 
diff --git a/db/post_migrate/20170502101023_cleanup_namespaceless_pending_delete_projects.rb b/db/post_migrate/20170502101023_cleanup_namespaceless_pending_delete_projects.rb
index ce52de91cdd..c1e64f20109 100644
--- a/db/post_migrate/20170502101023_cleanup_namespaceless_pending_delete_projects.rb
+++ b/db/post_migrate/20170502101023_cleanup_namespaceless_pending_delete_projects.rb
@@ -37,11 +37,11 @@ class CleanupNamespacelessPendingDeleteProjects < ActiveRecord::Migration
 
   def find_batch
     projects = Arel::Table.new(:projects)
-    projects.project(projects[:id]).
-      where(projects[:pending_delete].eq(true)).
-      where(projects[:namespace_id].eq(nil)).
-      skip(@offset * BATCH_SIZE).
-      take(BATCH_SIZE).
-      to_sql
+    projects.project(projects[:id])
+      .where(projects[:pending_delete].eq(true))
+      .where(projects[:namespace_id].eq(nil))
+      .skip(@offset * BATCH_SIZE)
+      .take(BATCH_SIZE)
+      .to_sql
   end
 end
diff --git a/db/post_migrate/20170508170547_add_head_pipeline_for_each_merge_request.rb b/db/post_migrate/20170508170547_add_head_pipeline_for_each_merge_request.rb
index f742936f122..f77078ddd70 100644
--- a/db/post_migrate/20170508170547_add_head_pipeline_for_each_merge_request.rb
+++ b/db/post_migrate/20170508170547_add_head_pipeline_for_each_merge_request.rb
@@ -11,11 +11,11 @@ class AddHeadPipelineForEachMergeRequest < ActiveRecord::Migration
     pipelines = Arel::Table.new(:ci_pipelines)
     merge_requests = Arel::Table.new(:merge_requests)
 
-    head_id = pipelines.
-      project(Arel::Nodes::NamedFunction.new('max', [pipelines[:id]])).
-      from(pipelines).
-      where(pipelines[:ref].eq(merge_requests[:source_branch])).
-      where(pipelines[:project_id].eq(merge_requests[:source_project_id]))
+    head_id = pipelines
+      .project(Arel::Nodes::NamedFunction.new('max', [pipelines[:id]]))
+      .from(pipelines)
+      .where(pipelines[:ref].eq(merge_requests[:source_branch]))
+      .where(pipelines[:project_id].eq(merge_requests[:source_project_id]))
 
     sub_query = Arel::Nodes::SqlLiteral.new(Arel::Nodes::Grouping.new(head_id).to_sql)
 
diff --git a/db/post_migrate/20170526185901_remove_stage_id_index_from_builds.rb b/db/post_migrate/20170526185901_remove_stage_id_index_from_builds.rb
new file mode 100644
index 00000000000..3879cf9133b
--- /dev/null
+++ b/db/post_migrate/20170526185901_remove_stage_id_index_from_builds.rb
@@ -0,0 +1,18 @@
+class RemoveStageIdIndexFromBuilds < ActiveRecord::Migration
+  include Gitlab::Database::MigrationHelpers
+
+  DOWNTIME = false
+
+  disable_ddl_transaction!
+
+  def up
+    if index_exists?(:ci_builds, :stage_id)
+      remove_foreign_key(:ci_builds, column: :stage_id)
+      remove_concurrent_index(:ci_builds, :stage_id)
+    end
+  end
+
+  def down
+    # noop
+  end
+end
diff --git a/db/post_migrate/20170526185921_migrate_build_stage_reference.rb b/db/post_migrate/20170526185921_migrate_build_stage_reference.rb
index d2e7fc207f0..98c32d8284c 100644
--- a/db/post_migrate/20170526185921_migrate_build_stage_reference.rb
+++ b/db/post_migrate/20170526185921_migrate_build_stage_reference.rb
@@ -3,25 +3,17 @@ class MigrateBuildStageReference < ActiveRecord::Migration
 
   DOWNTIME = false
 
-  disable_ddl_transaction!
+  ##
+  # This is an empty migration, content has been moved to a new one:
+  # post migrate 20170526190000 MigrateBuildStageReferenceAgain
+  #
+  # See gitlab-org/gitlab-ce!12337 for more details.
 
   def up
-    disable_statement_timeout
-
-    stage_id = Arel.sql <<-SQL.strip_heredoc
-      (SELECT id FROM ci_stages
-         WHERE ci_stages.pipeline_id = ci_builds.commit_id
-           AND ci_stages.name = ci_builds.stage)
-    SQL
-
-    update_column_in_batches(:ci_builds, :stage_id, stage_id) do |table, query|
-      query.where(table[:stage_id].eq(nil))
-    end
+    # noop
   end
 
   def down
-    disable_statement_timeout
-
-    update_column_in_batches(:ci_builds, :stage_id, nil)
+    # noop
   end
 end
diff --git a/db/post_migrate/20170526190000_migrate_build_stage_reference_again.rb b/db/post_migrate/20170526190000_migrate_build_stage_reference_again.rb
new file mode 100644
index 00000000000..97cb242415d
--- /dev/null
+++ b/db/post_migrate/20170526190000_migrate_build_stage_reference_again.rb
@@ -0,0 +1,27 @@
+class MigrateBuildStageReferenceAgain < ActiveRecord::Migration
+  include Gitlab::Database::MigrationHelpers
+
+  DOWNTIME = false
+
+  disable_ddl_transaction!
+
+  def up
+    disable_statement_timeout
+
+    stage_id = Arel.sql <<-SQL.strip_heredoc
+      (SELECT id FROM ci_stages
+         WHERE ci_stages.pipeline_id = ci_builds.commit_id
+           AND ci_stages.name = ci_builds.stage)
+    SQL
+
+    update_column_in_batches(:ci_builds, :stage_id, stage_id) do |table, query|
+      query.where(table[:stage_id].eq(nil))
+    end
+  end
+
+  def down
+    disable_statement_timeout
+
+    update_column_in_batches(:ci_builds, :stage_id, nil)
+  end
+end
diff --git a/db/post_migrate/20170621102400_add_stage_id_index_to_builds.rb b/db/post_migrate/20170621102400_add_stage_id_index_to_builds.rb
new file mode 100644
index 00000000000..7d6609b18bf
--- /dev/null
+++ b/db/post_migrate/20170621102400_add_stage_id_index_to_builds.rb
@@ -0,0 +1,21 @@
+class AddStageIdIndexToBuilds < ActiveRecord::Migration
+  include Gitlab::Database::MigrationHelpers
+
+  DOWNTIME = false
+
+  disable_ddl_transaction!
+
+  def up
+    unless index_exists?(:ci_builds, :stage_id)
+      add_concurrent_foreign_key(:ci_builds, :ci_stages, column: :stage_id, on_delete: :cascade)
+      add_concurrent_index(:ci_builds, :stage_id)
+    end
+  end
+
+  def down
+    if index_exists?(:ci_builds, :stage_id)
+      remove_foreign_key(:ci_builds, column: :stage_id)
+      remove_concurrent_index(:ci_builds, :stage_id)
+    end
+  end
+end
diff --git a/db/schema.rb b/db/schema.rb
index f42827991aa..028556bdccf 100644
--- a/db/schema.rb
+++ b/db/schema.rb
@@ -11,7 +11,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema.define(version: 20170614115405) do
+ActiveRecord::Schema.define(version: 20170621102400) do
 
   # These are extensions that must be enabled in order to support this database
   enable_extension "plpgsql"
@@ -777,6 +777,7 @@ ActiveRecord::Schema.define(version: 20170614115405) do
   add_index "merge_requests", ["created_at"], name: "index_merge_requests_on_created_at", using: :btree
   add_index "merge_requests", ["deleted_at"], name: "index_merge_requests_on_deleted_at", using: :btree
   add_index "merge_requests", ["description"], name: "index_merge_requests_on_description_trigram", using: :gin, opclasses: {"description"=>"gin_trgm_ops"}
+  add_index "merge_requests", ["head_pipeline_id"], name: "index_merge_requests_on_head_pipeline_id", using: :btree
   add_index "merge_requests", ["milestone_id"], name: "index_merge_requests_on_milestone_id", using: :btree
   add_index "merge_requests", ["source_branch"], name: "index_merge_requests_on_source_branch", using: :btree
   add_index "merge_requests", ["source_project_id"], name: "index_merge_requests_on_source_project_id", using: :btree