gitlab-org--gitlab-foss/db/migrate/20160725104020_merge_request_diff_remove_uniq.rb
Yorick Peterse fd4ad65462
Fix migration for removing MR diff indexes
For whatever reason on some PostgreSQL installations there would be a
separate UNIQUE constraint on the merge_request_id column. Rails'
index_exists?() returns false for this constraint (even when using the
full name), yet the indexes() method returns it.

This commit changes the migration so that the constraint is dropped as
well. MySQL installations don't appear to be affected.

Fixes gitlab-org/gitlab-ce#22136
2016-09-14 16:18:49 +02:00

35 lines
1.1 KiB
Ruby

# See http://doc.gitlab.com/ce/development/migration_style_guide.html
# for more information on how to write migrations for GitLab.
class MergeRequestDiffRemoveUniq < ActiveRecord::Migration
include Gitlab::Database::MigrationHelpers
disable_ddl_transaction!
DOWNTIME = false
def up
constraint_name = 'merge_request_diffs_merge_request_id_key'
transaction do
if index_exists?(:merge_request_diffs, :merge_request_id)
remove_index(:merge_request_diffs, :merge_request_id)
end
# In some bizarre cases PostgreSQL might have a separate unique constraint
# that we'll need to drop.
if constraint_exists?(constraint_name) && Gitlab::Database.postgresql?
execute("ALTER TABLE merge_request_diffs DROP CONSTRAINT IF EXISTS #{constraint_name};")
end
end
end
def down
unless index_exists?(:merge_request_diffs, :merge_request_id)
add_concurrent_index(:merge_request_diffs, :merge_request_id, unique: true)
end
end
def constraint_exists?(name)
indexes(:merge_request_diffs).map(&:name).include?(name)
end
end