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WITH RecursiveDepartments AS (
    SELECT
        ID,
        DepartmentName,
        ParentID
    FROM
        tblDepartment
    WHERE
        DepartmentName = 'Математический факультет'

    UNION ALL

    SELECT
        d.ID,
        d.DepartmentName,
        d.ParentID
    FROM
        tblDepartment d
    INNER JOIN
        RecursiveDepartments rd ON d.ParentID = rd.ID
)
SELECT
    DepartmentName
FROM
    RecursiveDepartments;