Add indexes to fields commonly filtered on for sending emails

db/migrate/20240711122121_add_indexes_to_email_related_filters.rb

@@ -0,0 +1,9 @@
+class AddIndexesToEmailRelatedFilters < ActiveRecord::Migration[7.1]
+  disable_ddl_transaction!
+
+  def change
+    add_index :candidates, :submission_blocked, algorithm: :concurrently
+    add_index :candidates, :account_locked, algorithm: :concurrently
+    add_index :candidates, :unsubscribed_from_emails, algorithm: :concurrently
+  end
+end

db/schema.rb

@@ -400,9 +400,12 @@
     t.boolean "submission_blocked", default: false, null: false
     t.boolean "account_locked", default: false, null: false
     t.string "account_recovery_status", default: "not_started", null: false
+    t.index ["account_locked"], name: "index_candidates_on_account_locked"
     t.index ["email_address"], name: "index_candidates_on_email_address", unique: true
     t.index ["fraud_match_id"], name: "index_candidates_on_fraud_match_id"
     t.index ["magic_link_token"], name: "index_candidates_on_magic_link_token", unique: true
+    t.index ["submission_blocked"], name: "index_candidates_on_submission_blocked"
+    t.index ["unsubscribed_from_emails"], name: "index_candidates_on_unsubscribed_from_emails"
   end
 
   create_table "chasers_sent", force: :cascade do |t|