Efficient sql server paging - sql-server-2008

Question

Due to the first two comments I've removed all my own code and placed the example directly from 4 guys here.
I'm interested in how the 'select #first_id' should be coded. The example shows the rows being pulled using joins and I would expect that the first_id wouldn't be a valid place to start because it doesn't use the same join syntax.
CREATE PROCEDURE [dbo].[usp_PageResults_NAI]
(
#startRowIndex int,
#maximumRows int
)
AS
DECLARE #first_id int, #startRow int
-- A check can be added to make sure #startRowIndex isn't > count(1)
-- from employees before doing any actual work unless it is guaranteed
-- the caller won't do that
-- Get the first employeeID for our page of records
SET ROWCOUNT #startRowIndex
SELECT #first_id = employeeID FROM employees ORDER BY employeeid
-- Now, set the row count to MaximumRows and get
-- all records >= #first_id
SET ROWCOUNT #maximumRows
SELECT e.*, d.name as DepartmentName
FROM employees e
INNER JOIN Departments D ON
e.DepartmentID = d.DepartmentID
WHERE employeeid >= #first_id
ORDER BY e.EmployeeID
SET ROWCOUNT 0
GO

Answer 1

You can to efficient paging using ROW_NUMBER()
DECLARE #skipRows Int = 10 --Change to input parameter to sp
DECLARE #takeRows Int = 20 --Change to input parameter to sp
SELECT *
FROM (
SELECT
ROW_NUMBER() OVER (ORDER BY a.DateCreated) As RowNumber,
a.PKID,
a.AlertUrl,
a.AlertDescription,
a.Users_PKID_creator,
dbo.Users_GetFullName(a.Users_PKID_creator) as Users_FullName,
a.Dealers_PKID,
d.Dealer,
dbo.convertDateFromUTC(a.DateCreated, #dealers_pkid) as DateCreated,
dbo.convertDateFromUTC(a.DateCreated, #dealers_pkid) as ComparisonDate,
dbo.convertDateFromUTC(a.DateModified, #dealers_pkid) as DateModified,
a.Active,
a.Contacts_PKID,
dbo.Contacts_GetFullName(a.Contacts_PKID) as Contacts_FullName
from Alerts a
join Dealers d on d.PKID = a.Dealers_PKID
where a.DateCreated between dbo.convertDateToUTC(#datetimeDateStart, #dealers_pkid) and dbo.convertDateToUTC(#datetimeDateEnd, #dealers_pkid)
and a.Active = #bitActive
and a.PKID >= #first_id
) AS [t1]
WHERE [t1].RowNumber BETWEEN #skipRows + 1 AND #skipRows + #takeRows