📄 41068.htm
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<P>分区可以通过使用这两个策略之一或者将两个策略有效的结合到一起来实现。关于策略 I 和 策略 II可以参考下面的表格，其中解释了这两个策略对影响关系型数据仓库分区因素的作用。</P>
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<P class=Label style="MARGIN: 3pt 0cm"><SPAN lang=EN-US style="mso-fareast-language: ZH-CN"><?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" /><o:p><FONT face=Verdana size=2><STRONG> </STRONG></FONT></o:p></SPAN></P></TD>
<TD style="BORDER-RIGHT: silver 1pt solid; PADDING-RIGHT: 4pt; BORDER-TOP: silver 1pt solid; PADDING-LEFT: 4pt; BACKGROUND: #e2e2e2; PADDING-BOTTOM: 0cm; BORDER-LEFT: #ece9d8; WIDTH: 148.65pt; PADDING-TOP: 0cm; BORDER-BOTTOM: silver 1pt solid; mso-border-alt: solid silver .5pt; mso-shading: windowtext; mso-pattern: gray-50 silver; mso-border-left-alt: solid silver .5pt" vAlign=top width=198>
<P class=Label style="MARGIN: 3pt 0cm"><FONT size=2><STRONG><SPAN style="FONT-FAMILY: 宋体; mso-fareast-language: ZH-CN; mso-ascii-font-family: Verdana; mso-hansi-font-family: Verdana">策略</SPAN><SPAN lang=EN-US><FONT face=Verdana> I</FONT></SPAN></STRONG></FONT></P></TD>
<TD style="BORDER-RIGHT: silver 1pt solid; PADDING-RIGHT: 4pt; BORDER-TOP: silver 1pt solid; PADDING-LEFT: 4pt; BACKGROUND: #e2e2e2; PADDING-BOTTOM: 0cm; BORDER-LEFT: #ece9d8; WIDTH: 148.7pt; PADDING-TOP: 0cm; BORDER-BOTTOM: silver 1pt solid; mso-border-alt: solid silver .5pt; mso-shading: windowtext; mso-pattern: gray-50 silver; mso-border-left-alt: solid silver .5pt" vAlign=top width=198>
<P class=Label style="MARGIN: 3pt 0cm"><STRONG><FONT size=2><SPAN style="FONT-FAMILY: 宋体; mso-fareast-language: ZH-CN; mso-ascii-font-family: Verdana; mso-hansi-font-family: Verdana">策略</SPAN><SPAN lang=EN-US><FONT face=Verdana> II</FONT></SPAN></FONT></STRONG></P></TD></TR>
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<TD style="BORDER-RIGHT: silver 1pt solid; PADDING-RIGHT: 4pt; BORDER-TOP: #ece9d8; PADDING-LEFT: 4pt; PADDING-BOTTOM: 0cm; BORDER-LEFT: silver 1pt solid; WIDTH: 148.65pt; PADDING-TOP: 0cm; BORDER-BOTTOM: silver 1pt solid; BACKGROUND-COLOR: transparent; mso-border-alt: solid silver .5pt; mso-border-top-alt: solid silver .5pt" vAlign=top width=198>
<P class=Text style="MARGIN: 3pt 0cm"><SPAN><FONT size=2><STRONG>数据导入</STRONG><o:p></o:p></FONT></SPAN></P></TD>
<TD style="BORDER-RIGHT: silver 1pt solid; PADDING-RIGHT: 4pt; BORDER-TOP: #ece9d8; PADDING-LEFT: 4pt; PADDING-BOTTOM: 0cm; BORDER-LEFT: #ece9d8; WIDTH: 148.65pt; PADDING-TOP: 0cm; BORDER-BOTTOM: silver 1pt solid; BACKGROUND-COLOR: transparent; mso-border-alt: solid silver .5pt; mso-border-left-alt: solid silver .5pt; mso-border-top-alt: solid silver .5pt" vAlign=top width=198>
<P class=BulletedList1 style="MARGIN: 3pt 0cm 3pt 18pt"><SPAN lang=EN-US style="FONT-FAMILY: Symbol; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol"><SPAN style="mso-list: Ignore"><FONT size=2>·</FONT><SPAN style="FONT: 7pt 'Times New Roman'"> </SPAN></SPAN></SPAN><FONT size=2><SPAN style="FONT-FAMILY: 宋体; mso-fareast-language: ZH-CN; mso-ascii-font-family: Verdana; mso-hansi-font-family: Verdana">在</SPAN><SPAN lang=EN-US><FONT face=Verdana>SELECT/INTO SQL</FONT></SPAN><SPAN style="FONT-FAMILY: 宋体; mso-fareast-language: ZH-CN; mso-ascii-font-family: Verdana; mso-hansi-font-family: Verdana">语句中不能明确的指定文件组。由于这一限制，在使用一个</SPAN><SPAN lang=EN-US><FONT face=Verdana>SELECT/INTO </FONT></SPAN><SPAN style="FONT-FAMILY: 宋体; mso-fareast-language: ZH-CN; mso-ascii-font-family: Verdana; mso-hansi-font-family: Verdana">语句时无法采用并行方式来完成初始转换</SPAN></FONT></P>
<P class=BulletedList1 style="MARGIN: 3pt 0cm 3pt 18pt"><SPAN lang=EN-US style="FONT-FAMILY: Symbol; mso-fareast-language: ZH-CN; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol"><SPAN style="mso-list: Ignore"><FONT size=2>·</FONT><SPAN style="FONT: 7pt 'Times New Roman'"> </SPAN></SPAN></SPAN><FONT size=2><SPAN style="FONT-FAMILY: 宋体; mso-fareast-language: ZH-CN; mso-ascii-font-family: Verdana; mso-hansi-font-family: Verdana">步进的数据导入不会被分区策略所影响</SPAN><SPAN lang=EN-US style="mso-fareast-language: ZH-CN"><o:p></o:p></SPAN></FONT></P></TD>
<TD style="BORDER-RIGHT: silver 1pt solid; PADDING-RIGHT: 4pt; BORDER-TOP: #ece9d8; PADDING-LEFT: 4pt; PADDING-BOTTOM: 0cm; BORDER-LEFT: #ece9d8; WIDTH: 148.7pt; PADDING-TOP: 0cm; BORDER-BOTTOM: silver 1pt solid; BACKGROUND-COLOR: transparent; mso-border-alt: solid silver .5pt; mso-border-left-alt: solid silver .5pt; mso-border-top-alt: solid silver .5pt" vAlign=top width=198>
<P class=BulletedList1 style="MARGIN: 3pt 0cm 3pt 18pt"><SPAN lang=EN-US style="FONT-FAMILY: Symbol; mso-fareast-language: ZH-CN; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol"><SPAN style="mso-list: Ignore"><FONT size=2>·</FONT><SPAN style="FONT: 7pt 'Times New Roman'"> </SPAN></SPAN></SPAN><FONT size=2><SPAN style="FONT-FAMILY: 宋体; mso-fareast-language: ZH-CN; mso-ascii-font-family: Verdana; mso-hansi-font-family: Verdana">当所有的分区映射到同一个文件组时转换可以采用并行的方式完成</SPAN><SPAN lang=EN-US style="mso-fareast-language: ZH-CN"><o:p></o:p></SPAN></FONT></P>
<P class=BulletedList1 style="MARGIN: 3pt 0cm 3pt 18pt"><SPAN lang=EN-US style="FONT-FAMILY: Symbol; mso-fareast-language: ZH-CN; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol"><SPAN style="mso-list: Ignore"><FONT size=2>·</FONT><SPAN style="FONT: 7pt 'Times New Roman'"> </SPAN></SPAN></SPAN><FONT size=2><SPAN style="FONT-FAMILY: 宋体; mso-fareast-language: ZH-CN; mso-ascii-font-family: Verdana; mso-hansi-font-family: Verdana">步进的数据导入不会被分区策略所影响</SPAN><SPAN lang=EN-US style="mso-fareast-language: ZH-CN"><o:p></o:p></SPAN></FONT></P></TD></TR>
<TR style="mso-yfti-irow: 2; mso-yfti-lastrow: yes">
<TD style="BORDER-RIGHT: silver 1pt solid; PADDING-RIGHT: 4pt; BORDER-TOP: #ece9d8; PADDING-LEFT: 4pt; PADDING-BOTTOM: 0cm; BORDER-LEFT: silver 1pt solid; WIDTH: 148.65pt; PADDING-TOP: 0cm; BORDER-BOTTOM: silver 1pt solid; BACKGROUND-COLOR: transparent; mso-border-alt: solid silver .5pt; mso-border-top-alt: solid silver .5pt" vAlign=top width=198>
<P class=Text style="MARGIN: 3pt 0cm"><FONT size=2><B style="mso-bidi-font-weight: normal"><SPAN style="FONT-FAMILY: 宋体; mso-fareast-language: ZH-CN; mso-ascii-font-family: Verdana; mso-hansi-font-family: Verdana">备份</SPAN><SPAN lang=EN-US><FONT face=Verdana>/</FONT></SPAN></B><B style="mso-bidi-font-weight: normal"><SPAN style="FONT-FAMILY: 宋体; mso-fareast-language: ZH-CN; mso-ascii-font-family: Verdana; mso-hansi-font-family: Verdana">还原</SPAN></B><SPAN lang=EN-US style="mso-fareast-language: ZH-CN"><o:p></o:p></SPAN></FONT></P></TD>
<TD style="BORDER-RIGHT: silver 1pt solid; PADDING-RIGHT: 4pt; BORDER-TOP: #ece9d8; PADDING-LEFT: 4pt; PADDING-BOTTOM: 0cm; BORDER-LEFT: #ece9d8; WIDTH: 148.65pt; PADDING-TOP: 0cm; BORDER-BOTTOM: silver 1pt solid; BACKGROUND-COLOR: transparent; mso-border-alt: solid silver .5pt; mso-border-left-alt: solid silver .5pt; mso-border-top-alt: solid silver .5pt" vAlign=top width=198>
<P class=BulletedList1 style="MARGIN: 3pt 0cm 3pt 18pt"><SPAN lang=EN-US style="FONT-FAMILY: Symbol; mso-fareast-language: ZH-CN; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol"><SPAN style="mso-list: Ignore"><FONT size=2>·</FONT><SPAN style="FONT: 7pt 'Times New Roman'"> </SPAN></SPAN></SPAN><FONT size=2><SPAN style="FONT-FAMILY: 宋体; mso-fareast-language: ZH-CN; mso-ascii-font-family: Verdana; mso-hansi-font-family: Verdana">在文件组和分区之间创建一个一一对应的关系让在分区级别的零散备份和还原操作得以进行</SPAN><SPAN lang=EN-US style="mso-fareast-language: ZH-CN"><o:p></o:p></SPAN></FONT></P>
<P class=BulletedList1 style="MARGIN: 3pt 0cm 3pt 18pt"><SPAN lang=EN-US style="FONT-FAMILY: Symbol; mso-fareast-language: ZH-CN; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol"><SPAN style="mso-list: Ignore"><FONT size=2>·</FONT><SPAN style="FONT: 7pt 'Times New Roman'"> </SPAN></SPAN></SPAN><FONT size=2><SPAN style="FONT-FAMILY: 宋体; mso-fareast-language: ZH-CN; mso-ascii-font-family: Verdana; mso-hansi-font-family: Verdana">在备份数据库之前确保分区被标记了只读状态。如果没有，当还原数据库时事务日志必须被前滚</SPAN><SPAN lang=EN-US style="mso-fareast-language: ZH-CN"><o:p></o:p></SPAN></FONT></P></TD>
<TD style="BORDER-RIGHT: silver 1pt solid; PADDING-RIGHT: 4pt; BORDER-TOP: #ece9d8; PADDING-LEFT: 4pt; PADDING-BOTTOM: 0cm; BORDER-LEFT: #ece9d8; WIDTH: 148.7pt; PADDING-TOP: 0cm; BORDER-BOTTOM: silver 1pt solid; BACKGROUND-COLOR: transparent; mso-border-alt: solid silver .5pt; mso-border-left-alt: solid silver .5pt; mso-border-top-alt: solid silver .5pt" vAlign=top width=198>
<P class=BulletedList1 style="MARGIN: 3pt 0cm 3pt 18pt"><SPAN lang=EN-US style="FONT-FAMILY: Symbol; mso-fareast-language: ZH-CN; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol"><SPAN style="mso-list: Ignore"><FONT size=2>·</FONT><SPAN style="FONT: 7pt 'Times New Roman'"> </SPAN></SPAN></SPAN><FONT size=2><SPAN style="FONT-FAMILY: 宋体; mso-fareast-language: ZH-CN; mso-ascii-font-family: Verdana; mso-hansi-font-family: Verdana">如果所有的分区被映射到了同一个文件组，分区表作为一个整体可以使用单个的命令进行备份和还原</SPAN><SPAN lang=EN-US style="mso-fareast-language: ZH-CN"><o:p></o:p></SPAN></FONT></P>
<P class=BulletedList1 style="MARGIN: 3pt 0cm 3pt 18pt"><SPAN lang=EN-US style="FONT-FAMILY: Symbol; mso-fareast-language: ZH-CN; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol"><SPAN style="mso-list: Ignore"><FONT size=2>·</FONT><SPAN style="FONT: 7pt 'Times New Roman'"> </SPAN></SPAN></SPAN><FONT size=2><SPAN style="FONT-FAMILY: 宋体; mso-fareast-language: ZH-CN; mso-ascii-font-family: Verdana; mso-hansi-font-family: Verdana">此策略在单个分区的粒度下不提供零散备份的灵活性</SPAN><SPAN lang=EN-US style="mso-fareast-language: ZH-CN"><o:p></o:p></SPAN></FONT></P></TD></TR></TBODY></TABLE></P>
<P class=Text style="MARGIN: 3pt 0cm"><SPAN lang=EN-US style="mso-fareast-language: ZH-CN"><o:p><FONT face=Verdana size=2> </FONT></o:p></SPAN></P>
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<TABLE class=MsoNormalTable style="BORDER-RIGHT: medium none; BORDER-TOP: medium none; MARGIN: auto auto auto 4pt; BORDER-LEFT: medium none; BORDER-BOTTOM: medium none; BORDER-COLLAPSE: collapse; mso-table-layout-alt: fixed; mso-border-alt: solid silver .5pt; mso-padding-alt: 0cm 4.0pt 0cm 4.0pt; mso-border-insideh: .5pt solid silver; mso-border-insidev: .5pt solid silver" cellSpacing=0 cellPadding=0 border=1>
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<TR style="mso-yfti-irow: 0; mso-yfti-firstrow: yes; mso-yfti-lastrow: yes">
<TD style="BORDER-RIGHT: silver 1pt solid; PADDING-RIGHT: 4pt; BORDER-TOP: silver 1pt solid; PADDING-LEFT: 4pt; PADDING-BOTTOM: 0cm; BORDER-LEFT: silver 1pt solid; WIDTH: 148.65pt; PADDING-TOP: 0cm; BORDER-BOTTOM: silver 1pt solid; BACKGROUND-COLOR: transparent; mso-border-alt: solid silver .5pt" vAlign=top width=198>
<P class=Text style="MARGIN: 3pt 0cm"><FONT size=2><B style="mso-bidi-font-weight: normal"><SPAN style="FONT-FAMILY: 宋体; mso-fareast-language: ZH-CN; mso-ascii-font-family: Verdana; mso-hansi-font-family: Verdana">查询性能</SPAN></B><SPAN lang=EN-US style="mso-fareast-language: ZH-CN"><o:p></o:p></SPAN></FONT></P></TD>
<TD style="BORDER-RIGHT: silver 1pt solid; PADDING-RIGHT: 4pt; BORDER-TOP: silver 1pt solid; PADDING-LEFT: 4pt; PADDING-BOTTOM: 0cm; BORDER-LEFT: #ece9d8; WIDTH: 148.65pt; PADDING-TOP: 0cm; BORDER-BOTTOM: silver 1pt solid; BACKGROUND-COLOR: transparent; mso-border-alt: solid silver .5pt; mso-border-left-alt: solid silver .5pt" vAlign=top width=198>
<P class=BulletedList1 style="MARGIN: 3pt 0cm 3pt 18pt"><SPAN lang=EN-US style="FONT-FAMILY: Symbol; mso-fareast-language: ZH-CN; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol"><SPAN style="mso-list: Ignore"><FONT size=2>·</FONT><SPAN style="FONT: 7pt 'Times New Roman'"> </SPAN></SPAN></SPAN><FONT size=2><SPAN style="FONT-FAMILY: 宋体; mso-fareast-language: ZH-CN; mso-ascii-font-family: Verdana; mso-hansi-font-family: Verdana">如果文件组只包含一个文件，并且表会采用一个接一个的串行方式来进行填充，对这样的对象的扩展盘区的分配是连续的。这意味着</SPAN><SPAN lang=EN-US style="mso-fareast-language: ZH-CN"><FONT face=Verdana>SQL Server</FONT></SPAN><SPAN style="FONT-FAMILY: 宋体; mso-fareast-language: ZH-CN; mso-ascii-font-family: Verdana; mso-hansi-font-family: Verdana">对于一个连续的扫描可以提供多达</SPAN><SPAN lang=EN-US style="mso-fareast-language: ZH-CN"><FONT face=Verdana>256 KB</FONT></SPAN><SPAN style="FONT-FAMILY: 宋体; mso-fareast-language: ZH-CN; mso-ascii-font-family: Verdana; mso-hansi-font-family: Verdana">的</SPAN><SPAN lang=EN-US style="mso-fareast-language: ZH-CN"><FONT face=Verdana> I/O (4</FONT></SPAN><SPAN style="FONT-FAMILY: 宋体; mso-fareast-language: ZH-CN; mso-ascii-font-family: Verdana; mso-hansi-font-family: Verdana">个扩展盘区</SPAN><SPAN lang=EN-US style="mso-fareast-language: ZH-CN"><FONT face=Verdana>)</FONT></SPAN><SPAN style="FONT-FAMILY: 宋体; mso-fareast-language: ZH-CN; mso-ascii-font-family: Verdana; mso-hansi-font-family: Verdana">速率</SPAN><SPAN lang=EN-US style="mso-fareast-language: ZH-CN"><o:p></o:p></SPAN></FONT></P>
<P class=BulletedList1 style="MARGIN: 3pt 0cm 3pt 18pt"><SPAN lang=EN-US style="FONT-FAMILY: Symbol; mso-fareast-language: ZH-CN; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol"><SPAN style="mso-list: Ignore"><FONT size=2>·</FONT><SPAN style="FONT: 7pt 'Times New Roman'"> </SPAN></SPAN></SPAN><FONT size=2><SPAN style="FONT-FAMILY: 宋体; mso-fareast-language: ZH-CN; mso-ascii-font-family: Verdana; mso-hansi-font-family: Verdana">因为数据是连续的，因此对于大量的连续扫描可以提供更好的工作负荷</SPAN><SPAN lang=EN-US style="mso-fareast-language: ZH-CN"><o:p></o:p></SPAN></FONT></P></TD>
<TD style="BORDER-RIGHT: silver 1pt solid; PADDING-RIGHT: 4pt; BORDER-TOP: silver 1pt solid; PADDING-LEFT: 4pt; PADDING-BOTTOM: 0cm; BORDER-LEFT: #ece9d8; WIDTH: 148.7pt; PADDING-TOP: 0cm; BORDER-BOTTOM: silver 1pt solid; BACKGROUND-COLOR: transparent; mso-border-alt: solid silver .5pt; mso-border-left-alt: solid silver .5pt" vAlign=top width=198>
<P class=BulletedList1 style="MARGIN: 3pt 0cm 3pt 18pt"><SPAN lang=EN-US style="FONT-FAMILY: Symbol; mso-fareast-language: ZH-CN; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol"><SPAN style="mso-list: Ignore"><FONT size=2>·</FONT><SPAN style="FONT: 7pt 'Times New Roman'"> </SPAN></SPAN></SPAN><FONT size=2><SPAN style="FONT-FAMILY: 宋体; mso-fareast-language: ZH-CN; mso-ascii-font-family: Verdana; mso-hansi-font-family: Verdana">如果文件组是由多个文件组成的，</SPAN><SPAN lang=EN-US style="mso-fareast-language: ZH-CN"><FONT face=Verdana>SQL Server</FONT></SPAN><SPAN style="FONT-FAMILY: 宋体; mso-fareast-language: ZH-CN; mso-ascii-font-family: Verdana; mso-hansi-font-family: Verdana">使用按比例填充机制，这样会导致扩展盘区出现碎片</SPAN><SPAN lang=EN-US style="mso-fareast-language: ZH-CN"><o:p></o:p></SPAN></FONT></P>
<P class=BulletedList1 style="MARGIN: 3pt 0cm 3pt 18pt"><SPAN lang=EN-US style="FONT-FAMILY: Symbol; mso-fareast-language: ZH-CN; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol"><SPAN style="mso-list: Ignore"><FONT size=2>·</FONT><SPAN style="FONT: 7pt 'Times New Roman'"> </SPAN></SPAN></SPAN><FONT size=2><SPAN style="FONT-FAMILY: 宋体; mso-fareast-language: ZH-CN; mso-ascii-font-family: Verdana; mso-hansi-font-family: Verdana">类似的，在并行操作比如并行数据导入操作期间为对象</SPAN><SPAN lang=EN-US style="mso-fareast-language: ZH-CN"><FONT face=Verdana>/</FONT></SPAN><SPAN style="FONT-FAMILY: 宋体; mso-fareast-language: ZH-CN; mso-ascii-font-family: Verdana; mso-hansi-font-family: Verdana">分区分配的扩展盘区无法保证是连续的</SPAN><SPAN lang=EN-US style="mso-fareast-language: ZH-CN"><FONT face=Verdana> <o:p></o:p></FONT></SPAN></FONT></P>
<P class=BulletedList1 style="MARGIN: 3pt 0cm 3pt 18pt"><SPAN lang=EN-US style="FONT-FAMILY: Symbol; mso-fareast-language: ZH-CN; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol"><SPAN style="mso-list: Ignore"><FONT size=2>·</FONT><SPAN style="FONT: 7pt 'Times New Roman'"> </SPAN></SPAN></SPAN><FONT size=2><SPAN style="FONT-FAMILY: 宋体; mso-fareast-language: ZH-CN; mso-ascii-font-family: Verdana; mso-hansi-font-family: Verdana">当为对象分配的扩展盘区不连续时，对于连续扫描</SPAN><SPAN lang=EN-US style="mso-fareast-language: ZH-CN"><FONT face=Verdana>SQL Server</FONT></SPAN><SPAN style="FONT-FAMILY: 宋体; mso-fareast-language: ZH-CN; mso-ascii-font-family: Verdana; mso-hansi-font-family: Verdana">可以提供差不多</SPAN><SPAN lang=EN-US style="mso-fareast-language: ZH-CN"><FONT face=Verdana>64 KB</FONT></SPAN><SPAN style="FONT-FAMILY: 宋体; mso-fareast-language: ZH-CN; mso-ascii-font-family: Verdana; mso-hansi-font-family: Verdana">的</SPAN><SPAN lang=EN-US style="mso-fareast-language: ZH-CN"><FONT face=Verdana> I/O</FONT></SPAN><SPAN style="FONT-FAMILY: 宋体; mso-fareast-language: ZH-CN; mso-ascii-font-family: Verdana; mso-hansi-font-family: Verdana">（</SPAN><SPAN lang=EN-US style="mso-fareast-language: ZH-CN"><FONT face=Verdana>1</FONT></SPAN><SPAN style="FONT-FAMILY: 宋体; mso-fareast-language: ZH-CN; mso-ascii-font-family: Verdana; mso-hansi-font-family: Verdana">个扩展盘区）速率</SPAN><SPAN lang=EN-US style="mso-fareast-language: ZH-CN"><o:p></o:p></SPAN></FONT></P>
<P class=BulletedList1 style="MARGIN: 3pt 0cm 3pt 18pt"><SPAN lang=EN-US style="FONT-FAMILY: Symbol; mso-fareast-language: ZH-CN; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol"><SPAN style="mso-list: Ignore"><FONT size=2>·</FONT><SPAN style="FONT: 7pt 'Times New Roman'"> </SPAN></SPAN></SPAN><FONT size=2><SPAN style="FONT-FAMILY: 宋体; mso-fareast-language: ZH-CN; mso-ascii-font-family: Verdana; mso-hansi-font-family: Verdana">因为数据分布在许多的物理磁盘上，因此它有助于在进行大量的并发随机</SPAN><SPAN lang=EN-US style="mso-fareast-language: ZH-CN"><FONT face=Verdana>I/O</FONT></SPAN><SPAN style="FONT-FAMILY: 宋体; mso-fareast-language: ZH-CN; mso-ascii-font-family: Verdana; mso-hansi-font-family: Verdana">操作时提供更好的工作负荷性能</SPAN><SPAN lang=EN-US style="mso-fareast-language: ZH-CN"><o:p></o:p></SPAN></FONT></P>
<P class=Text style="MARGIN: 3pt 0cm"><FONT size=2><SPAN style="FONT-FAMILY: 宋体; mso-fareast-language: ZH-CN; mso-ascii-font-family: Verdana; mso-hansi-font-family: Verdana">作为一个替换的方案，可以在启动</SPAN><SPAN lang=EN-US style="mso-fareast-language: ZH-CN"><FONT face=Verdana>SQL Server</FONT></SPAN><SPAN style="FONT-FAMILY: 宋体; mso-fareast-language: ZH-CN; mso-ascii-font-family: Verdana; mso-hansi-font-family: Verdana">时加上</SPAN><SPAN lang=EN-US style="mso-fareast-language: ZH-CN"><FONT face=Verdana>-E</FONT></SPAN><SPAN style="FONT-FAMILY: 宋体; mso-fareast-language: ZH-CN; mso-ascii-font-family: Verdana; mso-hansi-font-family: Verdana">开关。当在启动时指定了</SPAN><SPAN lang=EN-US style="mso-fareast-language: ZH-CN"><FONT face=Verdana>-E</FONT></SPAN><SPAN style="FONT-FAMILY: 宋体; mso-fareast-language: ZH-CN; mso-ascii-font-family: Verdana; mso-hansi-font-family: Verdana">开关时，</SPAN><SPAN lang=EN-US style="mso-fareast-language: ZH-CN"><FONT face=Verdana>SQL Server</FONT></SPAN><SPAN style="FONT-FAMILY: 宋体; mso-fareast-language: ZH-CN; mso-ascii-font-family: Verdana; mso-hansi-font-family: Verdana">可以分配</SPAN><SPAN lang=EN-US style="mso-fareast-language: ZH-CN"><FONT face=Verdana>4</FONT></SPAN><SPAN style="FONT-FAMILY: 宋体; mso-fareast-language: ZH-CN; mso-ascii-font-family: Verdana; mso-hansi-font-family: Verdana">个而不是</SPAN><SPAN lang=EN-US style="mso-fareast-language: ZH-CN"><FONT face=Verdana>1</FONT></SPAN><SPAN style="FONT-FAMILY: 宋体; mso-fareast-language: ZH-CN; mso-ascii-font-family: Verdana; mso-hansi-font-family: Verdana">个扩展盘区。因而</SPAN><SPAN lang=EN-US style="mso-fareast-language: ZH-CN"><FONT face=Verdana>-E</FONT></SPAN><SPAN style="FONT-FAMILY: 宋体; mso-fareast-language: ZH-CN; mso-ascii-font-family: Verdana; mso-hansi-font-family: Verdana">开关让</SPAN><SPAN lang=EN-US style="mso-fareast-language: ZH-CN"><FONT face=Verdana>SQL Server</FONT></SPAN><SPAN style="FONT-FAMILY: 宋体; mso-fareast-language: ZH-CN; mso-ascii-font-family: Verdana; mso-hansi-font-family: Verdana">可以提供多达</SPAN><SPAN lang=EN-US style="mso-fareast-language: ZH-CN"><FONT face=Verdana>256 KB </FONT></SPAN><SPAN style="FONT-FAMILY: 宋体; mso-fareast-language: ZH-CN; mso-ascii-font-family: Verdana; mso-hansi-font-family: Verdana">的</SPAN><SPAN lang=EN-US style="mso-fareast-language: ZH-CN"><FONT face=Verdana>I/O</FONT></SPAN><SPAN style="FONT-FAMILY: 宋体; mso-fareast-language: ZH-CN; mso-ascii-font-family: Verdana; mso-hansi-font-family: Verdana">速率，即使存在因使用了按比例填充机制而产生的扩展盘区碎片</SPAN></FONT><SPAN lang=EN-US style="mso-fareast-language: ZH-CN"><o:p></o:p></SPAN></P></TD></TR></TBODY></TABLE></P>
<P><STRONG>结论</STRONG></P>
<P>本白皮书讨论了影响分区的因素，以及对于设计分区可使用的两个主要策略的正反两面的对比。这里所提供的信息可能会对通过分区更有效的管理你的关系型数据仓库有所帮助。</P>
<P>有关的更多信息，请访问:http://www.microsoft.com/sql/</P>
<P>本文档展示了SQL Server 2005的一些与关系型数据仓库分区的相关特殊的功能。需要更多的信息，请参阅： </P>
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