Remove temporary blocking issues indexes

Remove temporary indexes used to schedule background
migrations.

changelogs/unreleased/issue_258973.yml

+---
+title: Remove temporary blocking issues scheduling indexes
+merge_request: 48064
+author:
+type: other

db/migrate/20201208181411_remove_temporary_blocking_issues_index.rb

+# frozen_string_literal: true
+
+class RemoveTemporaryBlockingIssuesIndex < ActiveRecord::Migration[6.0]
+  include Gitlab::Database::MigrationHelpers
+
+  DOWNTIME = false
+
+  disable_ddl_transaction!
+
+  def up
+    remove_concurrent_index_by_name(:issue_links, 'tmp_idx_blocking_type_links')
+    remove_concurrent_index_by_name(:issue_links, 'tmp_idx_blocked_by_type_links')
+    remove_concurrent_index_by_name(:issues, 'tmp_idx_index_issues_with_outdate_blocking_count')
+  end
+
+  def down
+    add_concurrent_index :issue_links, [:source_id], where: 'link_type = 1', name: 'tmp_idx_blocking_type_links'
+    add_concurrent_index :issue_links, [:target_id], where: 'link_type = 2', name: 'tmp_idx_blocked_by_type_links'
+    add_concurrent_index :issues, :id, where: '(state_id = 1 AND blocking_issues_count = 0)', name: 'tmp_idx_index_issues_with_outdate_blocking_count'
+  end
+end

db/schema_migrations/20201208181411

+7bbd0cfb98c3e051942bf062444d2586588fe029d9a9548f0e50e0fbad10a490
\ No newline at end of file

db/structure.sql

@@ -22776,12 +22776,6 @@ CREATE UNIQUE INDEX term_agreements_unique_index ON term_agreements USING btree
 
 CREATE INDEX tmp_build_stage_position_index ON ci_builds USING btree (stage_id, stage_idx) WHERE (stage_idx IS NOT NULL);
 
-CREATE INDEX tmp_idx_blocked_by_type_links ON issue_links USING btree (target_id) WHERE (link_type = 2);
-
-CREATE INDEX tmp_idx_blocking_type_links ON issue_links USING btree (source_id) WHERE (link_type = 1);
-
-CREATE INDEX tmp_idx_index_issues_with_outdate_blocking_count ON issues USING btree (id) WHERE ((state_id = 1) AND (blocking_issues_count = 0));
-
 CREATE INDEX tmp_index_for_email_unconfirmation_migration ON emails USING btree (id) WHERE (confirmed_at IS NOT NULL);
 
 CREATE UNIQUE INDEX unique_merge_request_metrics_by_merge_request_id ON merge_request_metrics USING btree (merge_request_id);