SELECT nb naauthor_name FROM novel_book nb where id = #id LEFT JOIN novel_author na ON nbauthor_id = naauthor_id 这个sql有问题吗

这个 SQL 语句有问题。应该将 LEFT JOIN 放在 WHERE 语句之前，如下所示：

SELECT nb.*, na.author_name FROM novel_book nb LEFT JOIN novel_author na ON nb.author_id = na.author_id WHERE nb.id = #{id}