18 lines
621 B
Ruby
18 lines
621 B
Ruby
|
class RemoveDuplicateTags < ActiveRecord::Migration
|
||
|
def up
|
||
|
select_all("SELECT name, COUNT(id) as cnt FROM tags GROUP BY name HAVING COUNT(id) > 1").each do |tag|
|
||
|
tag_name = quote_string(tag["name"])
|
||
|
duplicate_ids = select_all("SELECT id FROM tags WHERE name = '#{tag_name}'").map{|tag| tag["id"]}
|
||
|
origin_tag_id = duplicate_ids.first
|
||
|
duplicate_ids.delete origin_tag_id
|
||
|
|
||
|
execute("UPDATE taggings SET tag_id = #{origin_tag_id} WHERE tag_id IN(#{duplicate_ids.join(",")})")
|
||
|
execute("DELETE FROM tags WHERE id IN(#{duplicate_ids.join(",")})")
|
||
|
end
|
||
|
end
|
||
|
|
||
|
def down
|
||
|
|
||
|
end
|
||
|
end
|