AbstractThreadStrategy::setRuntime

protected function setRuntime(): void
{
	$this->runtime = [
		new ReferenceField(
			'MAILING_SUB', 'Bitrix\Sender\MailingSubscriptionTable', [
			'=this.CONTACT_ID'         => 'ref.CONTACT_ID',
			'=this.POSTING.MAILING_ID' => 'ref.MAILING_ID'
		], ['join_type' => 'LEFT']
		),
		new ExpressionField(
			'LAST_DIGIT', 'RIGHT(`sender_posting_recipient`.`ID`,1)'
		)
	];
}