diff options
Diffstat (limited to 'db/migrate/20170516153305_migrate_assignee_to_separate_table.rb')
-rw-r--r-- | db/migrate/20170516153305_migrate_assignee_to_separate_table.rb | 83 |
1 files changed, 83 insertions, 0 deletions
diff --git a/db/migrate/20170516153305_migrate_assignee_to_separate_table.rb b/db/migrate/20170516153305_migrate_assignee_to_separate_table.rb new file mode 100644 index 00000000000..f269ca7fc34 --- /dev/null +++ b/db/migrate/20170516153305_migrate_assignee_to_separate_table.rb @@ -0,0 +1,83 @@ +# See http://doc.gitlab.com/ce/development/migration_style_guide.html +# for more information on how to write migrations for GitLab. + +class MigrateAssigneeToSeparateTable < 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 + drop_table(:issue_assignees) if table_exists?(:issue_assignees) + + if Gitlab::Database.mysql? + execute <<-EOF + CREATE TABLE issue_assignees AS + SELECT assignee_id AS user_id, id AS issue_id FROM issues WHERE assignee_id IS NOT NULL + EOF + else + ActiveRecord::Base.transaction do + execute('LOCK TABLE issues IN EXCLUSIVE MODE') + + execute <<-EOF + CREATE TABLE issue_assignees AS + SELECT assignee_id AS user_id, id AS issue_id FROM issues WHERE assignee_id IS NOT NULL + EOF + + execute <<-EOF + CREATE OR REPLACE FUNCTION replicate_assignee_id() + RETURNS trigger AS + $BODY$ + BEGIN + if OLD.assignee_id IS NOT NULL THEN + DELETE FROM issue_assignees WHERE issue_id = OLD.id; + END IF; + + if NEW.assignee_id IS NOT NULL THEN + INSERT INTO issue_assignees (user_id, issue_id) VALUES (NEW.assignee_id, NEW.id); + END IF; + + RETURN NEW; + END; + $BODY$ + LANGUAGE 'plpgsql' + VOLATILE; + + CREATE TRIGGER replicate_assignee_id + BEFORE INSERT OR UPDATE OF assignee_id + ON issues + FOR EACH ROW EXECUTE PROCEDURE replicate_assignee_id(); + EOF + end + end + end + + def down + drop_table(:issue_assignees) if table_exists?(:issue_assignees) + + if Gitlab::Database.postgresql? + execute <<-EOF + DROP TRIGGER IF EXISTS replicate_assignee_id ON issues; + DROP FUNCTION IF EXISTS replicate_assignee_id(); + EOF + end + end +end |