ошибка пропущенного ключевого слова в oracle, когда я попробовал концепцию with-clause в CTE

Question

ниже мой код:

WITH Recursive EmployeeCTE AS

(
 Select Employee_Id as e_id, first_Name as e_name, Manager_ID as mgr_id
 From Employees
 Where Employee_Id =&emp_id

 union all

Select Employees.Employee_Id as e_id, Employees.first_Name as e_name, Employees.Manager_ID as mgr_id
 From Employees
 JOIN EmployeeCTE
 ON Employees.Employee_Id = EmployeeCTE.Manager_ID
)

Select E1.first_name, NVL(E2.first_Name, 'No Boss') as Manager_Name
From EmployeeCTE E1
LEFT Join EmployeeCTE E2
ON E1.Manager_ID = E2.Employee_Id;

Answer 1

Я думаю, что из-за ошибки, которую вы получаете, попробуйте указать псевдоним следующим образом:

WITH EMPLOYEECTE(E_ID, E_NAME, MGR_ID) AS (
    SELECT
        EMPLOYEE_ID   AS E_ID,
        FIRST_NAME    AS E_NAME,
        MANAGER_ID    AS MGR_ID
    FROM
        EMPLOYEES
    WHERE
        EMPLOYEE_ID = &EMP_ID
    UNION ALL
    SELECT
        EMPLOYEES.EMPLOYEE_ID   AS E_ID,
        EMPLOYEES.FIRST_NAME    AS E_NAME,
        EMPLOYEES.MANAGER_ID    AS MGR_ID
    FROM
        EMPLOYEES
        JOIN EMPLOYEECTE ON EMPLOYEES.EMPLOYEE_ID = EMPLOYEECTE.MGR_ID
)

Select E1.FIRST_NAME,
         NVL(E2.E_NAME, 'No Boss') AS MANAGER_NAME
FROM
    EMPLOYEECTE E1
    LEFT JOIN EMPLOYEECTE E2 ON E1.MANAGER_ID = E2.E_ID;

Cheers !!