Merge branch '26868-fix-duplicate-backported-migrations' into 'master'

Rename duplicate migrations and skip them if table/columns are already present

Closes #26868

See merge request !8644

db/migrate/20161223034433_add_estimate_to_issuables_ce.rb

+class AddEstimateToIssuablesCe < ActiveRecord::Migration
+  include Gitlab::Database::MigrationHelpers
+
+  DOWNTIME = false
+
+  def change
+    unless column_exists?(:issues, :time_estimate)
+      add_column :issues, :time_estimate, :integer
+    end
+
+    unless column_exists?(:merge_requests, :time_estimate)
+      add_column :merge_requests, :time_estimate, :integer
+    end
+  end
+end

db/migrate/20161223034433_add_time_estimate_to_issuables.rb

-# See http://doc.gitlab.com/ce/development/migration_style_guide.html
-# for more information on how to write migrations for GitLab.
-
-class AddTimeEstimateToIssuables < 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" 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" make sure that this
-  # method 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 fails and can be retried or reverted easily.
-  #
-  # To disable transactions uncomment the following line and remove these
-  # comments:
-  # disable_ddl_transaction!
-
-  def change
-    add_column :issues, :time_estimate, :integer
-    add_column :merge_requests, :time_estimate, :integer
-  end
-end

db/migrate/20161223034646_create_timelogs.rb

-# See http://doc.gitlab.com/ce/development/migration_style_guide.html
-# for more information on how to write migrations for GitLab.
-
-class CreateTimelogs < 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" 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" make sure that this
-  # method 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 fails and can be retried or reverted easily.
-  #
-  # To disable transactions uncomment the following line and remove these
-  # comments:
-  # disable_ddl_transaction!
-
-  def change
-    create_table :timelogs do |t|
-      t.integer :time_spent, null: false
-      t.references :trackable, polymorphic: true
-      t.references :user
-
-      t.timestamps null: false
-    end
-
-    add_index :timelogs, [:trackable_type, :trackable_id]
-    add_index :timelogs, :user_id
-  end
-end

db/migrate/20161223034646_create_timelogs_ce.rb

+class CreateTimelogsCe < ActiveRecord::Migration
+  include Gitlab::Database::MigrationHelpers
+
+  DOWNTIME = false
+
+  def change
+    unless table_exists?(:timelogs)
+      create_table :timelogs do |t|
+        t.integer :time_spent, null: false
+        t.references :trackable, polymorphic: true
+        t.references :user
+
+        t.timestamps null: false
+      end
+
+      add_index :timelogs, [:trackable_type, :trackable_id]
+      add_index :timelogs, :user_id
+    end
+  end
+end