public function getWikidataInfo(Page $page): array
{
    if (empty($page->getWikidataId())) {
        return [];
    }

    $wikidataId = 'Q'.ltrim($page->getWikidataId(), 'Q');
    $lang = $page->getProject()->getLang();

    $sql = "SELECT term_type AS term, term_text
            FROM wikidatawiki_p.wb_terms
            WHERE term_full_entity_id = :wikidataId
            AND term_type IN ('label', 'description')
            AND term_language = :lang";

    return $this->executeProjectsQuery($sql, [
        'lang' => $lang,
        'wikidataId' => $wikidataId,
    ])->fetchAll();
}

public function getWikidataErrors(): array
{
    $errors = [];

    if (empty($this->getWikidataId())) {
        return [];
    }

    $wikidataInfo = $this->getRepository()->getWikidataInfo($this);

    $terms = array_map(function ($entry) {
        return $entry['term'];
    }, $wikidataInfo);

    $lang = $this->getLang();

    if (!in_array('label', $terms)) {
        $errors[] = [
            'prio' => 2,
            'name' => 'Wikidata',
            'notice' => "Label for language <em>$lang</em> is missing", // FIXME: i18n
            'explanation' => "See: <a target='_blank' " .
                "href='//www.wikidata.org/wiki/Help:Label'>Help:Label</a>",
        ];
    }

    if (!in_array('description', $terms)) {
        $errors[] = [
            'prio' => 3,
            'name' => 'Wikidata',
            'notice' => "Description for language <em>$lang</em> is missing", // FIXME: i18n
            'explanation' => "See: <a target='_blank' " .
                "href='//www.wikidata.org/wiki/Help:Description'>Help:Description</a>",
        ];
    }

    return $errors;
}