oracle 的start with connect by prior 的用法
1. select sys_connect_by_path(t.dept_id,'/') from syc_smg_dpt t start with t.dept_id='RT_DISTRICT_JN_01' connect by prior dept_id = parent_dept_id -------以'RT_DISTRICT_JN_01' 遍歷其作為父節點的所有值
結果:
/RT_DISTRICT_JN_01
/RT_DISTRICT_JN_01/RT_GROUP_JN_CAR1
/RT_DISTRICT_JN_01/RT_GROUP_JN_CAR2
/RT_DISTRICT_JN_01/RT_GROUP_JN_XYDM1_1
/RT_DISTRICT_JN_01/RT_GROUP_JN_XYDM1_2
/RT_DISTRICT_JN_01/RT_GROUP_JN_XYDM2_1
/RT_DISTRICT_JN_01/RT_GROUP_JN_XYDM3_1
2. select max(sys_connect_by_path(t.dept_id,'/')) from syc_smg_dpt t start with t.dept_id = 'RT_DISTRICT_JN_01' connect by prior dept_id = parent_dept_id; ---取最大值
結果: /RT_DISTRICT_JN_01/RT_GROUP_JN_XYDM3_1
3. select sys_connect_by_path(t.dept_id,'/') from syc_smg_dpt t start with t.dept_id='RT_DISTRICT_JN_01' connect by prior parent_dept_id = dept_id;
結果: /RT_DISTRICT_JN_01
/RT_DISTRICT_JN_01/RT_CHARGER_JN_01
/RT_DISTRICT_JN_01/RT_CHARGER_JN_01/RT_MANAGER_01
/RT_DISTRICT_JN_01/RT_CHARGER_JN_01/RT_MANAGER_01/PA012_RT_SYSTEM_01
4. select max(sys_connect_by_path(t.dept_id,'/')) from syc_smg_dpt t start with t.dept_id = 'RT_DISTRICT_JN_01' connect by prior parent_dept_id = dept_id;
結果：/RT_DISTRICT_JN_01/RT_CHARGER_JN_01/RT_MANAGER_01/PA012_RT_SYSTEM_01