Sql 使用HIERARCHYID时尝试获取祖先的列值

我正在评估HIERARCHYID数据类型，看看它是否能满足我对项目的需求。我希望使用它来获取给定员工ID的经理。我正在查看AdventureWorks DB（2012版）中的表，特别是Person.Person和HumanResources.employee表

我的问题是这样的：

SELECT 
    pp.LastName + ', ' + pp.FirstName AS Name,
    CAST(hre.NationalIdNumber AS BIGINT) AS Id,
    hre.LoginID,
    hre.OrganizationNode.GetAncestor(1) AS ManagerId,
    hre.JobTitle,
    hre.BirthDate,
    hre.MaritalStatus,
    hre.Gender,
    hre.HireDate
FROM 
    Person.Person pp
INNER JOIN 
    HumanResources.Employee hre ON pp.BusinessEntityID = hre.BusinessEntityID

现在我预料到了这一点，因为getAncenter（）是一个CLR函数，所以我本来可以像hre.OrganizationNode.getAncenter（1.NationaldNumber）那样作为ManagerId来执行，但我被告知我不值得这么快

我做错了什么

以后编辑

玩游戏让我想到了这一点，但这并不是最优的（或者是吗？）

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一个相关的子查询似乎为我做到了这一点：

SELECT 
    pp.LastName + ', ' + pp.FirstName AS Name,
    CAST(hre.NationalIdNumber AS BIGINT) AS Id,
    hre.LoginID,
    (
        SELECT NationalIDNumber
        FROM HumanResources.Employee AS m
        WHERE OrganizationNode = hre.OrganizationNode.GetAncestor(1)
    )AS ManagerId,
    hre.JobTitle,
    hre.BirthDate,
    hre.MaritalStatus,
    hre.Gender,
    hre.HireDate
FROM 
    Person.Person pp
INNER JOIN 
    HumanResources.Employee hre ON pp.BusinessEntityID = hre.BusinessEntityID

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谢谢你，本，这比我的工作要简单

SELECT 
    pp.LastName + ', ' + pp.FirstName AS Name,
    CAST(hre.NationalIdNumber AS BIGINT) AS Id,
    hre.LoginID,
    (
        SELECT NationalIDNumber
        FROM HumanResources.Employee AS m
        WHERE OrganizationNode = hre.OrganizationNode.GetAncestor(1)
    )AS ManagerId,
    hre.JobTitle,
    hre.BirthDate,
    hre.MaritalStatus,
    hre.Gender,
    hre.HireDate
FROM 
    Person.Person pp
INNER JOIN 
    HumanResources.Employee hre ON pp.BusinessEntityID = hre.BusinessEntityID