Oracle 中實現查找樹形結構節點功能

這個方法只是對Oracle10以上纔有效，對sqlserver、mysql沒有測試

select connect_by_isleaf isleaf,
            tb.switch_type_id,
            sys_connect_by_path(tb.package_id, '|') path,
            tb.record_type,
            tb.element_offset,
            tb.element_length,
            tb.element_encode_type,
            tb.element_align,
            tb.mask,
            tb.asn_type
            from (select b.switch_type_id,
                    b.package_id,
                    b.element_offset,
                    b.element_length,
                    b.element_encode_type,
                    nvl(b.element_align, 'L') element_align,
                    b.record_type,
                    nvl(b.mask, 'LH') mask,
                    b.asn_type,
                    b.switch_type_id || '|' || b.package_level || '|' || b.package_id level_child,
                    b.switch_type_id || '|' || (b.package_level - 1) || '|' || b.parent_package_id level_parent
                 from switch_asn_record b
                 ) tb
             start with tb.level_parent like '%|0|-1'
             connect by prior tb.level_child = tb.level_parent;

一、connect_by_isleaf是不是子節點；
二、sys_connect_by_path(tb.package_id, '|')   ==>  |xxx|xxx|xxx
三、start with tb.level_parent like '%|0|-1'  ==> 樹的遍歷以從什麼開始
四、connect by prior tb.level_child = tb.level_parent;  ==>此層遍歷以後，再將child做爲parent，繼續往下遍歷

 

 

 

select t.*, t.rowid from tbgm_goods_category t

--遞歸查出指定ID的全部上級節點
SELECT LPAD('',2*(LEVEL - 1), '') || gc.category_id AS category_id,gc.trade_id,gc.parent_category_id

　　FROM tbgm_goods_category gc

　　CONNECT BY PRIOR parent_category_id = category_id -- 找出全部DEPT_ID等於當前記錄PARENT_ID的記錄

　　START WITH category_id = 216              -- 從部門4開始遞歸查詢。

--遞歸查出指定ID的全部子級節點
SELECT LPAD('',2*(LEVEL - 1), '')||gc.category_id AS category_id,gc.trade_id,gc.parent_category_id,gc.category_depth

　　FROM tbgm_goods_category gc
         where category_depth <= (SELECT category_depth FROM tbgm_goods_category where category_id = 214)+1
　　CONNECT BY parent_category_id = PRIOR category_id -- 找出全部PARENT_ID等於當前記錄DEPT_ID的記錄。

　　START WITH category_id = 214          -- 從部門2開始遞歸查詢。
   
  

 

oracle 9I中查找一個節點的全部制葉子節點select   max(t.parent_category_id)keep(dense_rank last order by level)p,  max(t.category_id)keep(dense_rank last order by level)c,  max(t.category_name)keep(dense_rank last order by level)nfrom tbgm_goods_category tstart with t.parent_category_id=259connect by prior t.category_id=t.parent_category_id--and prior child_type=/'special/'group by rownum-level