1 files changed, 51 insertions, 0 deletions
diff --git a/db/migrate/20170608152747_prepare_events_table_for_push_events_migration.rb b/db/migrate/20170608152747_prepare_events_table_for_push_events_migration.rb
new file mode 100644
index 00000000000..f4f03bbabaf
--- /dev/null
+++ b/db/migrate/20170608152747_prepare_events_table_for_push_events_migration.rb
@@ -0,0 +1,51 @@
+# See http://doc.gitlab.com/ce/development/migration_style_guide.html
+# for more information on how to write migrations for GitLab.
+
+class PrepareEventsTableForPushEventsMigration < ActiveRecord::Migration
+  include Gitlab::Database::MigrationHelpers
+
+  # Set this constant to true if this migration requires downtime.
+  DOWNTIME = false
+
+  disable_ddl_transaction!
+
+  def up
+    # The order of these columns is deliberate and results in the following
+    # columns and sizes:
+    #
+    # * id (4 bytes)
+    # * project_id (4 bytes)
+    # * author_id (4 bytes)
+    # * target_id (4 bytes)
+    # * created_at (8 bytes)
+    # * updated_at (8 bytes)
+    # * action (2 bytes)
+    # * target_type (variable)
+    #
+    # Unfortunately we can't make the "id" column a bigint/bigserial as Rails 4
+    # does not support this properly.
+    create_table :events_for_migration do |t|
+      t.references :project,
+                   index: true,
+                   foreign_key: { on_delete: :cascade }
+
+      t.integer :author_id, index: true, null: false
+      t.integer :target_id
+
+      t.timestamps_with_timezone null: false
+
+      t.integer :action, null: false, limit: 2, index: true
+      t.string :target_type
+
+      t.index %i[target_type target_id]
+    end
+
+    # t.references doesn't like it when the column name doesn't make the table
+    # name so we have to add the foreign key separately.
+    add_concurrent_foreign_key(:events_for_migration, :users, column: :author_id)
+  end
+
+  def down
+    drop_table :events_for_migration
+  end
+end