The Execution Engine - Inside the SQL Server Query Optimizer - page 56

Figure 2-25: Properties of the Clustered Index Seek operator.
Let us change the query to add a filter by TerritoryID .
SELECT e . EmployeeID
FROM HumanResources . Employee AS e
INNER JOIN Sales . SalesPerson AS s
ON e . EmployeeID = s . SalesPersonID
WHERE TerritoryID = 1
Listing 2-28.
This query produces the plan in Figure 2-26.