public function delete($index)
    {
        $this
            ->db
            ->delete('ucms_search_index')
            ->condition('index_key', $index)
            ->execute()
        ;

        $this->indexer();
        $this->nodeIndexerChain->removeIndexer($index);

        $this->clearDefinitionCache();

        $this->moduleHandler->invokeAll(self::HOOK_DEF_DELETE, [$index]);

        $this->deleteInClient($index);
    }