eZ\Publish\Core\Search\Legacy\Content\WordIndexer\Repository\SearchIndex::purge PHP Method

    public function purge()
    {
        $this->dbHandler->beginTransaction();
        $query = $this->dbHandler->createDeleteQuery();
        $tables = ['ezsearch_object_word_link', 'ezsearch_return_count', 'ezsearch_search_phrase', 'ezsearch_word'];
        foreach ($tables as $tbl) {
            $query->deleteFrom($tbl);
            $stmt = $query->prepare();
            $stmt->execute();
        }
        $this->dbHandler->commit();
    }

 /**
  * Remove entire search index.
  */
 public function purgeIndex()
 {
     $this->searchIndex->purge();
 }