Question

我想写一个存储过程

create proc GetTrunk @trunk int, @tableName sysname, @trunksize int = 5000
as
with    t as ( 
           select PK1, PK2, ntile(@trunksize) over ( order by PK1, PK2 ) t
           from     ABigTable -- Just put table name directly here for testing
 -- the table has a composite pk of pk1 and pk2
         )
select  pk1, pk2
from    t
where   t = @trunk;

运行GetTrunk 3, 'tname', 5000会将表格切换为大小为5000的中继，并获取中继的第3主干密钥。

但是，对于大桌子来说这很慢。这是获得桌面窗口的更好方法吗？

Answer 1

您可以试用ORDER BY enhancements of OFFSET and FETCH。像这样：

create proc GetTrunk @trunk int, @tableName sysname, @trunksize int = 5000
as

           select PK1, PK2
           from     ABigTable 
           order by PK1, PK2 OFFSET ((@trunk -1) * @trunksize)  ROWS 
    FETCH NEXT @trunksize ROWS ONLY

我认为它的表现会比NTILE好。

将表切成大小为N的树干？

1 个答案: