46 lines
1.8 KiB
Ruby
46 lines
1.8 KiB
Ruby
# See http://doc.gitlab.com/ce/development/migration_style_guide.html
|
|
# for more information on how to write migrations for GitLab.
|
|
|
|
class AddPartialIndexForLabelsTemplate < 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!
|
|
|
|
# Note this is a partial index in Postgres but MySQL will ignore the
|
|
# partial index clause. By making it an index on "template" this
|
|
# means the index will still accomplish the same goal of optimizing
|
|
# a query with "where template = true" on MySQL -- it'll just take
|
|
# more space. In this case the number of records with template=true
|
|
# is expected to be very small (small enough to display on a single
|
|
# web page) so it's ok to filter or sort them without the index
|
|
# anyways.
|
|
|
|
def up
|
|
add_concurrent_index "labels", ["template"], where: "template"
|
|
end
|
|
|
|
def down
|
|
remove_concurrent_index "labels", ["template"], where: "template"
|
|
end
|
|
end
|