Merge branch 'fix_assignee_yourick_approach' into 'master'

Improve migration for Multipple issue assignee feature

See merge request !11417

1 files changed, 41 insertions, 0 deletions

diff --git a/db/migrate/20170516183131_add_indices_to_issue_assignees.rb b/db/migrate/20170516183131_add_indices_to_issue_assignees.rb
new file mode 100644
index 00000000000..a1f064c6848
--- /dev/null
+++ b/db/migrate/20170516183131_add_indices_to_issue_assignees.rb
@@ -0,0 +1,41 @@
+# See http://doc.gitlab.com/ce/development/migration_style_guide.html
+# for more information on how to write migrations for GitLab.
+
+class AddIndicesToIssueAssignees < ActiveRecord::Migration
+  include Gitlab::Database::MigrationHelpers
+
+  # Set this constant to true if this migration requires downtime.
+  DOWNTIME = false
+
+  # When a migration requires downtime you **must** uncomment the following
+  # constant and define a short and easy to understand explanation as to why the
+  # migration requires downtime.
+  # DOWNTIME_REASON = ''
+
+  # When using the methods "add_concurrent_index", "remove_concurrent_index" or
+  # "add_column_with_default" you must disable the use of transactions
+  # as these methods can not run in an existing transaction.
+  # When using "add_concurrent_index" or "remove_concurrent_index" methods make sure
+  # that either of them is the _only_ method called in the migration,
+  # any other changes should go in a separate migration.
+  # This ensures that upon failure _only_ the index creation or removing fails
+  # and can be retried or reverted easily.
+  #
+  # To disable transactions uncomment the following line and remove these
+  # comments:
+  disable_ddl_transaction!
+
+  def up
+    add_concurrent_index :issue_assignees, [:issue_id, :user_id], unique: true, name: 'index_issue_assignees_on_issue_id_and_user_id'
+    add_concurrent_index :issue_assignees, :user_id, name: 'index_issue_assignees_on_user_id'
+    add_concurrent_foreign_key :issue_assignees, :users, column: :user_id, on_delete: :cascade
+    add_concurrent_foreign_key :issue_assignees, :issues, column: :issue_id, on_delete: :cascade
+  end
+
+  def down
+    remove_foreign_key :issue_assignees, column: :user_id
+    remove_foreign_key :issue_assignees, column: :issue_id
+    remove_concurrent_index :issue_assignees, [:issue_id, :user_id] if index_exists?(:issue_assignees, [:issue_id, :user_id])
+    remove_concurrent_index :issue_assignees, :user_id if index_exists?(:issue_assignees, :user_id)
+  end
+end