SQL SERVER2012在ORDER BY 子句中加入了新元素offset,允许用户在排序完成的结果集中自定义输出行范围，大大简化了分页SQL的书写方式和效率。以下是与以前的两种分页方式的简单对比
use
master
go
set
nocount
on
go
set
showplan_text
on
go
--2012的OFFSET分页方式
select
number
from
spt_values
where
type
=
'
p
'
order
by
number
offset
10
rows
fetch
next
5
rows
only
;
go
--2005的ROW_NUMBER分页方式
select
number
from
(
select
number
,row_number()
over
(
order
by
number
)
as
num
from
spt_values
where
type
=
'
p
'
) t
where
num
between
11
and
15
order
by
number
asc
go
--2000的TOP分页方式
select
number
from
(
select
top
5
number
from
(
select
top
15
number
from
spt_values
where
type
=
'
p
'
order
by
number
asc
) t
order
by
number
desc
) t
order
by
number
asc
go
set
showplan_text
off
go
/*
StmtText
----------------------------------------------------------------------------------------------------------
select number
from spt_values
where type='p'
order by number offset 10 rows fetch next 5 rows only;
StmtText
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|--Top(OFFSET EXPRESSION:((10)),TOP EXPRESSION:((5)))
|--Index Scan(OBJECT:([mssqlsystemresource].[sys].[spt_values].[ix2_spt_values_nu_nc]), WHERE:(CONVERT(nchar(3),[mssqlsystemresource].[sys].[spt_values].[type],0)=N'p') ORDERED FORWARD)
StmtText
---------------------------------------------------------------------------------------------------------------------------------------------------------------------
select number from (
select number,row_number() over(order by number) as num from spt_values where type='p'
) t where num between 11 and 15
order by number asc
StmtText
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|--Sort(ORDER BY:([mssqlsystemresource].[sys].[spt_values].[number] ASC))
|--Filter(WHERE:([Expr1005]>=(11) AND [Expr1005]<=(15)))
|--Top(TOP EXPRESSION:(CASE WHEN (15) IS NULL OR (15)<(0) THEN (0) ELSE (15) END))
|--Sequence Project(DEFINE:([Expr1005]=row_number))
|--Segment
|--Index Scan(OBJECT:([mssqlsystemresource].[sys].[spt_values].[ix2_spt_values_nu_nc]), WHERE:(CONVERT(nchar(3),[mssqlsystemresource].[sys].[spt_values].[type],0)=N'p') ORDERED FORWARD)
StmtText
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
select number from (
select top 5 number from (
select top 15 number from spt_values where type='p' order by number asc
) t
order by number desc
) t
order by number asc
StmtText
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|--Sort(ORDER BY:([mssqlsystemresource].[sys].[spt_values].[number] ASC))
|--Sort(TOP 5, ORDER BY:([mssqlsystemresource].[sys].[spt_values].[number] DESC))
|--Top(TOP EXPRESSION:((15)))
|--Index Scan(OBJECT:([mssqlsystemresource].[sys].[spt_values].[ix2_spt_values_nu_nc]), WHERE:(CONVERT(nchar(3),[mssqlsystemresource].[sys].[spt_values].[type],0)=N'p') ORDERED FORWARD)
*/
从查询计划来看，2012的查询计划中，offset直接操作了top迭代器，分页计划十分简单，看起来也比后两种简单明了。
而在系统预估的查询开销中，OFFSET占9%，ROW_NUMBER占45%，TOP占47%（加起来101% -_-||）,OFFSET占了绝对的优势。
在2008的更新中，我最喜欢的是MERGE，2012中就是OFFSET了。
