帮助编写嵌套集的SQL查询

我正在行使嵌套集将数据库存储在数据库中.表的字段是id,lft,rgt和name.

给定一个节点ID,我必要找到它们本身的叶子节点的全部直接子节点(不是孙子节点).

办理要领

这是怎样找到节点的直接子节点：

SELECT node.name,(COUNT(parent.name) - (sub_tree.depth + 1)) AS depth
FROM nested_category AS node,nested_category AS parent,nested_category AS sub_parent,(
        SELECT node.name,(COUNT(parent.name) - 1) AS depth
        FROM nested_category AS node,nested_category AS parent
        WHERE node.lft BETWEEN parent.lft AND parent.rgt
        AND node.name = '**[[MY NODE]]**'
        GROUP BY node.name
        ORDER BY node.lft
    )AS sub_tree
WHERE node.lft BETWEEN parent.lft AND parent.rgt
    AND node.lft BETWEEN sub_parent.lft AND sub_parent.rgt
    AND sub_parent.name = sub_tree.name
GROUP BY node.name
HAVING depth = 1
ORDER BY node.lft;

然后将它与叶子节点的rgt便是lft 1这一究竟相团结,然后举办配置.包涵双关语.

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