discourse/db/migrate/20121123054127_make_post_nu...

29 lines
555 B
Ruby

class MakePostNumberDistinct < ActiveRecord::Migration[4.2]
def up
DB.exec('update posts p
set post_number = calc
from
(
select
id,
post_number,
topic_id,
row_number() over (partition by topic_id order by post_number, created_at) calc
from posts
where topic_id in (
select topic_id from posts
group by topic_id, post_number
having count(*)>1
)
) as X
where calc <> p.post_number and X.id = p.id')
end
def down
# don't want to mess with the index ... its annoying
raise ActiveRecord::IrreversibleMigration
end
end