For sorting in descending order you need to use: ORDER BY keyword
Your query should be like this -
SELECT summary FROM cms_module_cgblog WHERE cgblog_id=(SELECT article_id FROM cms_module_cgblog_tags_link WHERE tag_id=979 ORDER BY tag_id DESC LIMIT 1);
与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…