oracle - 如何使用分层查询获取所有经理的列表

Question

我想提取我的经理的员工名单。看看下面的查询：

SELECT   SYS_CONNECT_BY_PATH (username, ':') AS "Liste Membres",LEVEL
  FROM   employees
 WHERE   CONNECT_BY_ISLEAF = 1
         AND username = '150') -- My_code
START WITH   manager IS NULL
CONNECT BY   PRIOR username = manager 

这个查询的结果是：

:1:20:120:150

我想要得到的结果：

:1:20:120:

Answer 1

将其更改为SYS_CONNECT_BY_PATH (manager, ':')然后删除:为根级别NULL管理器附加的前导（如果您想要尾随，:则添加|| ':'）：

SQL小提琴

Oracle 11g R2 模式设置：

CREATE TABLE EMPLOYEES ( manager, username ) AS
  SELECT NULL, 1 FROM DUAL UNION ALL
  SELECT 1, 20 FROM DUAL UNION ALL
  SELECT 20, 120 FROM DUAL UNION ALL
  SELECT 120, 150 FROM DUAL;

查询 1：

SELECT   SUBSTR( SYS_CONNECT_BY_PATH (manager, ':'), 2 ) AS "Liste Membres",
         LEVEL
FROM     employees
WHERE    CONNECT_BY_ISLEAF = 1
AND      username = '150' -- My_code
START WITH   manager IS NULL
CONNECT BY   PRIOR username = manager 

结果：

| Liste Membres | LEVEL |
|---------------|-------|
|     :1:20:120 |     4 |