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Asked: 2026-05-18T07:04:41+00:00

Let’s say I’ve got the following table: CREATE TABLE Employees ( EmployeeId int PRIMARY

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Let’s say I’ve got the following table:

CREATE TABLE Employees
(
EmployeeId int PRIMARY KEY NOT NULL,
ParentEmployeId int REFERENCES Employees(EmployeeId) NULL,
Name varChar(255)
)

All records have a primary identifier and records are able to identify another record as a parent. (My actual schema isn’t about employees, this is just a simplified version for illustration so if you’ve got a better way of handling employee information its not germane to this conversation.)

The following records are inserted:

INSERT INTO Employees VALUES (1, NULL, 'Company President 1')
INSERT INTO Employees VALUES (2, NULL, 'Company President 2')

INSERT INTO Employees VALUES (3, 1, 'Company President 1 - VP')
INSERT INTO Employees VALUES (4, 2, 'Company President 2 - VP')

INSERT INTO Employees VALUES (5, 3, 'Company President 1 - VP - Secretary')
INSERT INTO Employees VALUES (6, 4, 'Company President 2 - VP - Secretary')

INSERT INTO Employees VALUES (7, 5, 'Company President 1 - VP - Secretary - Sandwich Delivery')

These inserts represent:

Company President 1
    Company President 1 - VP
        Company President 1 - VP - Secretary
            Company President 1 - VP - Secretary - Sandwich Delivery
Company President 2
    Company President 2 - VP
        Company President 2 - VP - Secretary

What I’m trying to do is for all employees that have a NULL ParentEmployeeId I want to find the last person in the chain, which in this example would be “Company President 1 - VP - Secretary - Sandwich Delivery” and “Company President 2 - VP - Secretary“.

I’ve got the following CTE which gives me everything including the nesting level but I’m not sure where to go from here. I’d like to avoid cursors if possible.

Also, and this is very important, I have logic elsewhere that guarantees that an employee can only have 1 direct subordinate. So although the schema technically allows for it, Company President 1 will never have two VP’s listed.

WITH EmployeeRec(EmployeeId, ParentEmployeeId, Name, Level) AS
(
    SELECT
        EmployeeId,
        ParentEmployeId,
        Name,
        1 as [Level]
    FROM
        Employees
    WHERE
        ParentEmployeId IS NULL

    UNION ALL

    SELECT
        E.EmployeeId,
        E.ParentEmployeId,
        E.Name,
        R.[Level] + 1
    FROM
        Employees E
    INNER JOIN
        EmployeeRec R
    ON
        E.ParentEmployeId = R.EmployeeId
)
SELECT * FROM EmployeeRec
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1 Answer

  1. Editorial Team

    Keeping track of your master EmployeeID allows you to join the results with the last level to retain the records you need.

    WITH EmployeeRec(Master, EmployeeId, ParentEmployeeId, Name, Level) AS
(
    SELECT
        [Master] = EmployeeId,
        EmployeeId,
        ParentEmployeId,
        Name,
        1 as [Level]
    FROM
        Employees
    WHERE
        ParentEmployeId IS NULL

    UNION ALL

    SELECT
        R.Master,
        E.EmployeeId,
        E.ParentEmployeId,
        E.Name,
        R.[Level] + 1
    FROM
        Employees E
    INNER JOIN
        EmployeeRec R
    ON
        E.ParentEmployeId = R.EmployeeId
)
SELECT  *
FROM    EmployeeRec er
        INNER JOIN (
          SELECT  Master, Level = MAX(Level)
          FROM    EmployeeRec
          GROUP BY Master
        ) m ON m.Master = er.Master
               AND m.Level = er.Level
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