Add compound index for `vulnerabilities` table on `project_id` and `id`

Changelog: performance

db/migrate/20220125230538_add_compound_index_on_project_id_and_id_for_vulnerabilities.rb

+# frozen_string_literal: true
+
+class AddCompoundIndexOnProjectIdAndIdForVulnerabilities < Gitlab::Database::Migration[1.0]
+  INDEX_NAME = 'index_vulnerabilities_on_project_id_and_id'
+
+  disable_ddl_transaction!
+
+  def up
+    add_concurrent_index :vulnerabilities, [:project_id, :id], name: INDEX_NAME
+  end
+
+  def down
+    remove_concurrent_index :vulnerabilities, [:project_id, :id], name: INDEX_NAME
+  end
+end

db/schema_migrations/20220125230538

+6f3a3712288c3316042426d60f087817eb57a3246b750831aa72f95f30269a5d
\ No newline at end of file

db/structure.sql

@@ -27951,6 +27951,8 @@ CREATE INDEX index_vulnerabilities_on_last_edited_by_id ON vulnerabilities USING
 
 CREATE INDEX index_vulnerabilities_on_milestone_id ON vulnerabilities USING btree (milestone_id);
 
+CREATE INDEX index_vulnerabilities_on_project_id_and_id ON vulnerabilities USING btree (project_id, id);
+
 CREATE INDEX index_vulnerabilities_on_project_id_and_state_and_severity ON vulnerabilities USING btree (project_id, state, severity);
 
 CREATE INDEX index_vulnerabilities_on_resolved_by_id ON vulnerabilities USING btree (resolved_by_id);