请教分页获取评论的MYSQL写法,可盖楼的评论
需要分页获取评论.例如每页20个.
但是我的评论是可以再进行评论的.再评论的评论可以再再被评论.....就是可盖楼.
就是说一个评论A可以有子评论,子评论可以再有子评论.即A的孙评论. 孙评论还可以有评论, A的重孙评论......无限分层.
评论字段有: id , 和 parent_id 如果是原始评论那么 parent_id 为0 .如果是子孙评论 那么parent_Id 就是其父亲的id.
想用一条 语句 limit 20条原始评论 以及 这20条的子子孙孙评论.
请教大家哦.
------解决方案--------------------
要实现你的要求，就不是只用 id 和 parent_id (邻接列表算法)能解决的了
你需要将数据组织方式转换成前序遍历算法（也称左右值算法、预排序算法）
具体实现你可以搜索一下
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