讨论数量:
@Insua 看了下 Nested set model 在查询上可能有飞快的感觉。
问题如下:
我想给 Suits 下在加一个 二股筋 (一种背心,英文实在是不知道怎么说),简称 Egj,这是该怎么做那?
SELECT
Child.*
FROM
tree AS Child,
tree AS Parent
WHERE
Child.depth = Parent.depth + 1
AND Parent.pid = 0
或者
SELECT
Child.*
FROM
tree AS Child,
tree AS Parent
WHERE
Child.depth = Parent.depth + 1
AND Child.`left` > Parent.`left`
AND Child.`right` < Parent.`right`
AND Parent.pid = 0
结果一样
Nested set model 这么做的优势在那里啊?
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