Lookup similar in SQL SERVER 2008, no R2 for MultipleDataSet

In SQL Server 2008 (not R2), the LOOKUP function is not available, but you can achieve similar functionality using JOIN operations in your SQL queries. 

Scenario:
- Dataset1: Contains code_person, name, and city_code
- Dataset2: Contains city_code and city_name

You want to join these datasets to get the city_name for each person in Dataset1.

Solution:
You can use a JOIN to combine the datasets based on the city_code.

SELECT 
    Dataset1.code_person,
    Dataset1.name,
    Dataset1.city_code,
    Dataset2.city_name
FROM 
    Dataset1
INNER JOIN 
    Dataset2
ON 
    Dataset1.city_code = Dataset2.city_code;