commit: 7fb850e987c92a6b863cc1f66a6ec7318460f1de parent: 1c5b0e333464d8da3de73e4886502c816cb8173e Author: unarist <m.unarist@gmail.com> Date: Tue, 28 Nov 2017 04:22:27 +0900 Merge indexes for reblog on statuses table (#5831) We added an index for `[account_id, reblog_of_id]`, but we already have a similar index for `reblog_of_id`. Those index will be bigger according to statuses count. For example, `reblog_of_id` index uses 800MB for 10GB statuses table. So this patch swaps indexed columns like `[reblog_of_id, account_id]`, then it will covers both usage with single index. Since those index creation may take a while, I've also disabled previous index creation.Diffstat:
4 files changed, 32 insertions(+), 6 deletions(-)
diff --git a/db/migrate/20171122120436_add_index_account_and_reblog_of_id_to_statuses.rb b/db/migrate/20171122120436_add_index_account_and_reblog_of_id_to_statuses.rb @@ -1,6 +1,12 @@ class AddIndexAccountAndReblogOfIdToStatuses < ActiveRecord::Migration[5.1] - def change - commit_db_transaction - add_index :statuses, [:account_id, :reblog_of_id], algorithm: :concurrently + disable_ddl_transaction! + + def up + # This index has been superseded by migration 20171125185353 + # add_index :statuses, [:account_id, :reblog_of_id], algorithm: :concurrently + end + + def down + remove_index :statuses, [:account_id, :reblog_of_id] if index_exists?(:statuses, [:account_id, :reblog_of_id]) end end diff --git a/db/migrate/20171125185353_add_index_reblog_of_id_and_account_to_statuses.rb b/db/migrate/20171125185353_add_index_reblog_of_id_and_account_to_statuses.rb @@ -0,0 +1,7 @@ +class AddIndexReblogOfIdAndAccountToStatuses < ActiveRecord::Migration[5.1] + disable_ddl_transaction! + + def change + add_index :statuses, [:reblog_of_id, :account_id], algorithm: :concurrently + end +end diff --git a/db/migrate/20171125190735_remove_old_reblog_index_on_statuses.rb b/db/migrate/20171125190735_remove_old_reblog_index_on_statuses.rb @@ -0,0 +1,14 @@ +class RemoveOldReblogIndexOnStatuses < ActiveRecord::Migration[5.1] + disable_ddl_transaction! + + def up + # This index may not exists (see migration 20171122120436) + remove_index :statuses, [:account_id, :reblog_of_id] if index_exists?(:statuses, [:account_id, :reblog_of_id]) + + remove_index :statuses, :reblog_of_id + end + + def down + add_index :statuses, :reblog_of_id, algorithm: :concurrently + end +end diff --git a/db/schema.rb b/db/schema.rb @@ -10,7 +10,7 @@ # # It's strongly recommended that you check this file into your version control system. -ActiveRecord::Schema.define(version: 20171125031751) do +ActiveRecord::Schema.define(version: 20171125190735) do # These are extensions that must be enabled in order to support this database enable_extension "plpgsql" @@ -409,10 +409,9 @@ ActiveRecord::Schema.define(version: 20171125031751) do t.bigint "application_id" t.bigint "in_reply_to_account_id" t.index ["account_id", "id"], name: "index_statuses_on_account_id_id" - t.index ["account_id", "reblog_of_id"], name: "index_statuses_on_account_id_and_reblog_of_id" t.index ["conversation_id"], name: "index_statuses_on_conversation_id" t.index ["in_reply_to_id"], name: "index_statuses_on_in_reply_to_id" - t.index ["reblog_of_id"], name: "index_statuses_on_reblog_of_id" + t.index ["reblog_of_id", "account_id"], name: "index_statuses_on_reblog_of_id_and_account_id" t.index ["uri"], name: "index_statuses_on_uri", unique: true end