SQLServer 表分区

SQL SERVER 2005中，终于引入了表分区，就是说，当一个表里的数据很多时，可以将其分拆到
多个的表里，大大提高了性能。下面举例子说明之

比如，在C盘下建立如下几个目录
C:\Data2\Primary
C:\Data2\FG1
C:\Data2\FG2
C:\Data2\FG3
C:\Data2\FG4

其中primary存放的是主数据库文件，其他FG1--FG4存放四个单独的文件组，可以见创立数据库
Data Partition DB2，如下

USE [master] GO /****** Object:  Database [Data Partition DB]    Script Date: 10/08/2006 23:09:53 ******/ IF  EXISTS (SELECT name FROM sys.databases WHERE name = N'Data Partition DB2') DROP DATABASE [Data Partition DB2] GO CREATE DATABASE [Data Partition DB2] ON PRIMARY (NAME='Data Partition DB Primary FG', FILENAME= 'C:\Data2\Primary\Data Partition DB Primary FG.mdf', SIZE=5, MAXSIZE=500, FILEGROWTH=1 ), FILEGROUP [Data Partition DB FG1] (NAME = 'Data Partition DB FG1', FILENAME = 'C:\Data2\FG1\Data Partition DB FG1.ndf', SIZE = 5MB, MAXSIZE=500, FILEGROWTH=1 ), FILEGROUP [Data Partition DB FG2] (NAME = 'Data Partition DB FG2', FILENAME = 'C:\Data2\FG2\Data Partition DB FG2.ndf', SIZE = 5MB, MAXSIZE=500, FILEGROWTH=1 ), FILEGROUP [Data Partition DB FG3] (NAME = 'Data Partition DB FG3', FILENAME = 'C:\Data2\FG3\Data Partition DB FG3.ndf', SIZE = 5MB, MAXSIZE=500, FILEGROWTH=1 ), FILEGROUP [Data Partition DB FG4] (NAME = 'Data Partition DB FG4', FILENAME = 'C:\Data2\FG4\Data Partition DB FG4.ndf', SIZE = 5MB, MAXSIZE=500, FILEGROWTH=1 ) 接下来，我们创建分区表函数，这其实可以理解为一个规则，说明如何以一个规则来将一个表来划分，如下
 use [Data Partition DB2] GO CREATE PARTITION FUNCTION [Data Partition Range](int) AS RANGE LEFT FOR VALUES (100,200,300) 其中分区函数的名称是Data Partition Range,后面的类型（int)表明接下来用来分区的那个字段的类型是INT类型，

而VALUES (100,200,300)表明，将把表分为4个区了，是从负数到100，100-200，200-300，大于300。

接下来，我们要创建分区架构，即将分区函数应用到我们分好的四个文件组里面去

USE [Data Partition DB2] go CREATE PARTITION SCHEME [Data Partition Scheme] AS PARTITION [Data Partition Range] TO ([Data Partition DB FG1], [Data Partition DB FG2], [Data Partition DB FG3],[Data Partition DB FG4]);

再创建表的结构
USE [Data Partition DB2]

go
CREATE TABLE MyTable
(ID INT NOT NULL, Date DATETIME, Cost money)    
   ON [Data Partition Scheme] (ID);

这里注意，ON [Data Partition Scheme] (ID);表明，划分时以ID的大小作为划分的根据，ON后要跟分区架购的名称

最后，我们可以填充数据了

USE [Data Partition DB2] go declare @count int set @count =-25 while @count <=100 begin insert into MyTable select @count,getdate(),100.00 set @count=@count+1 end set @count =101 while @count <=200 begin insert into MyTable select @count,getdate(),200.00 set @count=@count+1 end set @count =201 while @count <=300 begin insert into MyTable select @count,getdate(),300.00 set @count=@count+1 end set @count =301 while @count <=400 begin insert into MyTable select @count,getdate(),400.00 set @count=@count+1 end set @count =401 while @count <=800 begin insert into MyTable select @count,getdate(),500.00 set @count=@count+1 end 

最后，我们可以查询下，插入的这些数据，是否真的被划分到四个不同的文件组里的表分区了，可以这样看
SELECT *, $PARTITION.[Data Partition Range](ID)
 FROM MyTable