Beginning Microsoft SQL Server 2008 ... - S3 Tech Training

in your relational database. These new features are somewhat advanced and take quite a bit of effort to
master, so I am going to defer drilling into these topics. We’re going to consider them to be out of the
scope of this book — see the Advanced Data Structures chapter in Professional level title for more information
on the new HierarchyID data type.
If you would like to see examples of the new hierarchical functionality that is part of SQL
Server 2008, check out the OrganizationNode and OrganizationLevel columns of the
HumanResources.Employee table in AdventureWorks2008.
To continue our discussion of hierarchical data, we are going to handle hierarchies the way we’ve been
forced to for ages — call it the “old school method.” Since AdventureWorks2008 doesn't have an a good
example of this older (and still far more prevalent) way of doing hierarchical data, we'll create our own
version of the Employee table (we'll call it Employee2) that implements this “old school method” of
addressing hierarchies. If you ran the BuildAndPopulateEmployee2.sql file back in Chapter 3, then
you already have this new version of Employee. If you didn't, go ahead and execute it now (again, it is
available on the wrox.com or professionalsql.com websites).
The table created by this script is represented in Figure 13-1.
Figure 13-1
Assuming you've executed the script and have the Employee2 table, let's see if we can retrieve a list of
reports for Karla Huntington.
At first glance, this seems pretty easy. If we wanted to know all the people who report to Karla, we
might write a query that would join the Employee table back to itself — something like:
USE AdventureWorks2008;
SELECT
FROM
TheReport.EmployeeID,
TheReport.JobTitle,
TheReport.LastName,
TheReport.FirstName
Chapter 13: User-Defined Functions
HumanResources.Employee2 as TheBoss
JOIN HumanResources.Employee2 AS TheReport
ON TheBoss.EmployeeID = TheReport.ManagerID
WHERE TheBoss.LastName = ‘Huntington’ AND TheBoss.FirstName = ‘Karla’;
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