Sql server® 2012 t-sql fundamentals

The 

TOP

 and 

OFFSET-FETCH

 Filters

Earlier in this chapter, I covered filters that are based on the predicates WHERE and HAVING. In this 

section, I cover filters that are based on number of rows and ordering. I’ll start with a filter called TOP 

that has been supported in SQL Server for quite some time—since version 7.0. Then I’ll introduce a 

new filter called OFFSET-FETCH that was introduced in SQL Server 2012.

The 

TOP

 Filter

The TOP option is a proprietary T-SQL feature that allows you to limit the number or percentage of 

rows that your query returns. It relies on two elements as part of its specification; one is the number 

or percent of rows to return, and the other is the ordering. For example, to return from the Orders 

table the five most recent orders, you would specify TOP (5) in the SELECT clause and orderdate DESC 

in the ORDER BY clause, as shown in Listing 2-5.

LISTING 2-5

  Query Demonstrating the TOP Option

SELECT TOP (5) orderid, orderdate, custid, empid 

FROM Sales.Orders 

ORDER BY orderdate DESC;

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