MongoDB权威指南（1）- 入门
jopen
12年前
<div id="article_content" class="article_content"> <p style="line-height:20px;margin:5px auto;font-family:Verdana,Geneva,Arial,Helvetica,sans-serif;font-size:13px;">安装</p> <p style="line-height:20px;margin:5px auto;font-family:Verdana,Geneva,Arial,Helvetica,sans-serif;font-size:13px;"> 解压缩出来就OK了，mongoDB缺省使用磁盘根目录的data文件夹和data\db文件夹，</p> <p style="line-height:20px;margin:5px auto;font-family:Verdana,Geneva,Arial,Helvetica,sans-serif;font-size:13px;"> 这两个文件夹需要手工建立，如果想使用其他路径，那么启动mongoDB的时候需要指明路径</p> <p style="line-height:20px;margin:5px auto;font-family:Verdana,Geneva,Arial,Helvetica,sans-serif;font-size:13px;">运行</p> <p style="line-height:20px;margin:5px auto;font-family:Verdana,Geneva,Arial,Helvetica,sans-serif;font-size:13px;"> 运行CMD打开控制台窗口，导航至mongodb的bin目录，运行mongod.exe，服务器就启动起来了，按ctrl-c结束程序。</p> <p style="line-height:20px;margin:5px auto;font-family:Verdana,Geneva,Arial,Helvetica,sans-serif;font-size:13px;"> 另开一个控制台窗口，导航至mongodb的bin目录,运行mongo.exe来启动shell,就链接到服务器了，缺省连接到test数据库。</p> <p style="line-height:20px;margin:5px auto;font-family:Verdana,Geneva,Arial,Helvetica,sans-serif;font-size:13px;">-------------------------------------------------------------------------------------------------------------</p> <p style="line-height:20px;margin:5px auto;font-family:Verdana,Geneva,Arial,Helvetica,sans-serif;font-size:13px;">OK，第一章讲mongoDB如何如何牛b的我们就隔过去啦，这里直接是第二章。</p> <p style="line-height:20px;margin:5px auto;font-family:Verdana,Geneva,Arial,Helvetica,sans-serif;font-size:13px;"><strong>1.一些基本概念</strong></p> <p style="line-height:20px;margin:5px auto;font-family:Verdana,Geneva,Arial,Helvetica,sans-serif;font-size:13px;"> document ：mongoDB里边数据的基本单位，相当于关系数据库里的行</p> <p style="line-height:20px;margin:5px auto;font-family:Verdana,Geneva,Arial,Helvetica,sans-serif;font-size:13px;"> collection: 相当于关系数据库的表，不过是没有数据结构定义的</p> <p style="line-height:20px;margin:5px auto;font-family:Verdana,Geneva,Arial,Helvetica,sans-serif;font-size:13px;"> 每个mongoDB的实例可以运行多个database，每个database有自己的collection和权限控制</p> <p style="line-height:20px;margin:5px auto;font-family:Verdana,Geneva,Arial,Helvetica,sans-serif;font-size:13px;"> mongoDB拥有一个强大的javascript shell，用于管理数据库和操作数据</p> <p style="line-height:20px;margin:5px auto;font-family:Verdana,Geneva,Arial,Helvetica,sans-serif;font-size:13px;"> 每个document都有一个特殊的key："_id",这个值在collection内是唯一的</p> <p style="line-height:20px;margin:5px auto;font-family:Verdana,Geneva,Arial,Helvetica,sans-serif;font-size:13px;">document</p> <p style="line-height:20px;margin:5px auto;font-family:Verdana,Geneva,Arial,Helvetica,sans-serif;font-size:13px;">document是一组有序的key/value对，使用json风格的数据。</p> <div style="line-height:20px;font-family:Verdana,Geneva,Arial,Helvetica,sans-serif;font-size:13px;" class="cnblogs_Highlighter"> <div style="position:relative !important;text-align:left !important;padding-bottom:1px !important;border-right-width:0px !important;margin:1em 0px;padding-left:1px !important;outline-width:0px 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!important;right:auto !important;padding-top:0px !important;left:auto !important;" class="lines"> <div style="position:static !important;padding-bottom:0px !important;border-right-width:0px !important;margin:0px;padding-left:0px !important;outline-width:0px !important;width:auto !important;bottom:auto !important;padding-right:0px !important;float:none !important;border-top-width:0px !important;border-bottom-width:0px !important;height:auto !important;font-size:1em !important;vertical-align:baseline !important;border-left-width:0px !important;top:auto !important;right:auto !important;padding-top:0px !important;left:auto !important;" class="line alt1"> <table style="position:static !important;text-align:left !important;padding-bottom:0px !important;border-right-width:0px !important;margin:0px;padding-left:0px !important;outline-width:0px !important;width:auto !important;bottom:auto !important;padding-right:0px !important;border-collapse:collapse !important;float:none !important;border-top-width:0px !important;border-bottom-width:0px !important;height:auto !important;font-size:1em !important;vertical-align:baseline !important;border-left-width:0px !important;top:auto !important;right:auto !important;padding-top:0px !important;left:auto !important;" class="ke-zeroborder"> <tbody style="position:static !important;padding-bottom:0px !important;border-right-width:0px !important;margin:0px;padding-left:0px !important;outline-width:0px !important;width:auto !important;bottom:auto !important;padding-right:0px !important;float:none !important;border-top-width:0px !important;border-bottom-width:0px !important;height:auto !important;font-size:1em !important;vertical-align:baseline !important;border-left-width:0px !important;top:auto !important;right:auto !important;padding-top:0px !important;left:auto !important;"> <tr style="position:static !important;padding-bottom:0px !important;border-right-width:0px !important;margin:0px;padding-left:0px !important;outline-width:0px !important;width:auto !important;bottom:auto !important;padding-right:0px !important;float:none !important;border-top-width:0px !important;border-bottom-width:0px !important;height:auto !important;font-size:1em !important;vertical-align:baseline !important;border-left-width:0px !important;top:auto !important;right:auto !important;padding-top:0px !important;left:auto !important;"> <td style="position:static !important;padding-bottom:0px !important;border-right-width:0px !important;margin:0px;padding-left:0.5em !important;outline-width:0px !important;width:auto !important;bottom:auto !important;padding-right:0px !important;float:none !important;border-top-width:0px !important;border-bottom-width:0px !important;height:auto !important;font-size:1em !important;vertical-align:top !important;border-left-style:none !important;top:auto !important;right:auto !important;padding-top:0px !important;left:auto !important;" class="content"><code style="position:static !important;padding-bottom:0px !important;border-right-width:0px !important;margin:0px;padding-left:0px !important;outline-width:0px !important;width:auto !important;bottom:auto !important;padding-right:0px !important;font-family:Consolas,'Bitstream Vera Sans Mono','Courier New',Courier,monospace !important;float:none !important;border-top-width:0px !important;border-bottom-width:0px !important;height:auto !important;font-size:1em !important;vertical-align:baseline !important;border-left-width:0px !important;top:auto !important;right:auto !important;padding-top:0px !important;left:auto !important;" class="plain">{</code><code style="position:static !important;padding-bottom:0px !important;border-right-width:0px !important;margin:0px;padding-left:0px !important;outline-width:0px !important;width:auto !important;bottom:auto !important;padding-right:0px !important;font-family:Consolas,'Bitstream Vera Sans Mono','Courier New',Courier,monospace !important;float:none !important;border-top-width:0px !important;border-bottom-width:0px !important;height:auto !important;color:blue !important;font-size:1em !important;vertical-align:baseline !important;border-left-width:0px !important;top:auto !important;right:auto !important;padding-top:0px !important;left:auto !important;" class="string">"foo"</code> <code style="position:static !important;padding-bottom:0px !important;border-right-width:0px !important;margin:0px;padding-left:0px !important;outline-width:0px !important;width:auto !important;bottom:auto !important;padding-right:0px !important;font-family:Consolas,'Bitstream Vera Sans Mono','Courier New',Courier,monospace !important;float:none !important;border-top-width:0px !important;border-bottom-width:0px !important;height:auto !important;font-size:1em !important;vertical-align:baseline !important;border-left-width:0px !important;top:auto !important;right:auto !important;padding-top:0px !important;left:auto !important;" class="plain">: 3, </code><code style="position:static !important;padding-bottom:0px !important;border-right-width:0px !important;margin:0px;padding-left:0px !important;outline-width:0px !important;width:auto !important;bottom:auto !important;padding-right:0px !important;font-family:Consolas,'Bitstream Vera Sans Mono','Courier New',Courier,monospace !important;float:none !important;border-top-width:0px !important;border-bottom-width:0px !important;height:auto !important;color:blue !important;font-size:1em !important;vertical-align:baseline !important;border-left-width:0px !important;top:auto !important;right:auto !important;padding-top:0px !important;left:auto !important;" class="string">"greeting"</code> <code style="position:static !important;padding-bottom:0px !important;border-right-width:0px !important;margin:0px;padding-left:0px !important;outline-width:0px !important;width:auto !important;bottom:auto !important;padding-right:0px !important;font-family:Consolas,'Bitstream Vera Sans Mono','Courier New',Courier,monospace !important;float:none !important;border-top-width:0px !important;border-bottom-width:0px !important;height:auto !important;font-size:1em !important;vertical-align:baseline !important;border-left-width:0px !important;top:auto !important;right:auto !important;padding-top:0px !important;left:auto !important;" class="plain">: </code><code style="position:static !important;padding-bottom:0px !important;border-right-width:0px !important;margin:0px;padding-left:0px !important;outline-width:0px !important;width:auto !important;bottom:auto !important;padding-right:0px !important;font-family:Consolas,'Bitstream Vera Sans Mono','Courier New',Courier,monospace !important;float:none !important;border-top-width:0px !important;border-bottom-width:0px !important;height:auto !important;color:blue !important;font-size:1em !important;vertical-align:baseline !important;border-left-width:0px !important;top:auto !important;right:auto !important;padding-top:0px !important;left:auto !important;" class="string">"Hello, world!"</code><code style="position:static !important;padding-bottom:0px !important;border-right-width:0px !important;margin:0px;padding-left:0px !important;outline-width:0px !important;width:auto !important;bottom:auto !important;padding-right:0px !important;font-family:Consolas,'Bitstream Vera Sans Mono','Courier New',Courier,monospace !important;float:none !important;border-top-width:0px !important;border-bottom-width:0px !important;height:auto !important;font-size:1em !important;vertical-align:baseline !important;border-left-width:0px !important;top:auto !important;right:auto !important;padding-top:0px !important;left:auto !important;" class="plain">}</code></td> </tr> </tbody> </table> </div> </div> </div> </div> <p style="line-height:20px;margin:5px auto;font-family:Verdana,Geneva,Arial,Helvetica,sans-serif;font-size:13px;">key是个UTF-8字符串，value 可以是很多类型，甚至是一个嵌入的document。</p> <p style="line-height:20px;margin:5px auto;font-family:Verdana,Geneva,Arial,Helvetica,sans-serif;font-size:13px;">collection</p> <p style="line-height:20px;margin:5px auto;font-family:Verdana,Geneva,Arial,Helvetica,sans-serif;font-size:13px;">collection是一组document，它是无结构定义的，所以你可以把任何document存入一个collection里。</p> <p style="line-height:20px;margin:5px auto;font-family:Verdana,Geneva,Arial,Helvetica,sans-serif;font-size:13px;">subcollection</p> <p style="line-height:20px;margin:5px auto;font-family:Verdana,Geneva,Arial,Helvetica,sans-serif;font-size:13px;">一个习惯性的组织collection的方式，使用.号分隔，像命名空间。例如，程序里使用了一个blog，它可能包含一个collection叫 blog.post和另外一个collection叫blog.authors,这仅仅是出于组织内容的目的，它们俩看起来像是blog的子集，实际上他们没有任何关系，甚至blog也许就是不存在的。</p> <p style="line-height:20px;margin:5px auto;font-family:Verdana,Geneva,Arial,Helvetica,sans-serif;font-size:13px;">database</p> <p style="line-height:20px;margin:5px auto;font-family:Verdana,Geneva,Arial,Helvetica,sans-serif;font-size:13px;">一个mongoDB的实例可以运行多个database，database之间是完全独立的，每个database有自己的权限，每个database存储于磁盘的不同文件。</p> <p style="line-height:20px;margin:5px auto;font-family:Verdana,Geneva,Arial,Helvetica,sans-serif;font-size:13px;"><strong>2. mongoDB shell</strong></p> <p style="line-height:20px;margin:5px auto;font-family:Verdana,Geneva,Arial,Helvetica,sans-serif;font-size:13px;">shell本身就是一个javascript解释器，让我们来干点啥来看看</p> <p style="line-height:20px;margin:5px auto;font-family:Verdana,Geneva,Arial,Helvetica,sans-serif;font-size:13px;">可以进行数学运算</p> <div style="border-bottom:#cccccc 1px solid;border-left:#cccccc 1px solid;padding-bottom:5px;line-height:20px;overflow-x:auto;overflow-y:auto;background-color:#f5f5f5;padding-left:5px;padding-right:5px;font-family:'Courier New';word-break:break-all;border-top:#cccccc 1px solid;border-right:#cccccc 1px solid;padding-top:5px;" class="cnblogs_code"> <div> <span style="line-height:1.5;">></span> <span style="line-height:1.5;"> x </span> <span style="line-height:1.5;">=</span> <span style="line-height:1.5;"> </span> <span style="line-height:1.5;">200</span> <span style="line-height:1.5;"><br /> </span> <span style="line-height:1.5;">200</span> <span style="line-height:1.5;"><br /> </span> <span style="line-height:1.5;">></span> <span style="line-height:1.5;"> x </span> <span style="line-height:1.5;">/</span> <span style="line-height:1.5;"> </span> <span style="line-height:1.5;">5</span> <span style="line-height:1.5;">;<br /> </span> <span style="line-height:1.5;">40</span> </div> </div> <p style="line-height:20px;margin:5px auto;font-family:Verdana,Geneva,Arial,Helvetica,sans-serif;font-size:13px;">可以使用标准的javascript库</p> <div style="border-bottom:#cccccc 1px solid;border-left:#cccccc 1px solid;padding-bottom:5px;line-height:20px;overflow-x:auto;overflow-y:auto;background-color:#f5f5f5;padding-left:5px;padding-right:5px;font-family:'Courier New';word-break:break-all;border-top:#cccccc 1px solid;border-right:#cccccc 1px solid;padding-top:5px;" class="cnblogs_code"> <div> <span style="line-height:1.5;">></span> <span style="line-height:1.5;"> Math.sin(Math.PI </span> <span style="line-height:1.5;">/</span> <span style="line-height:1.5;"> </span> <span style="line-height:1.5;">2</span> <span style="line-height:1.5;">);<br /> </span> <span style="line-height:1.5;">1</span> <span style="line-height:1.5;"><br /> </span> <span style="line-height:1.5;">></span> <span style="line-height:1.5;"> </span> <span style="line-height:1.5;color:#0000ff;">new</span> <span style="line-height:1.5;"> Date(</span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">2010/1/1</span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">);<br /> </span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">Fri Jan 01 2010 00:00:00 GMT-0500 (EST)</span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;"><br /> </span> <span style="line-height:1.5;">></span> <span style="line-height:1.5;"> </span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">Hello, World!</span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">.replace(</span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">World</span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">, </span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">MongoDB</span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">);<br /> Hello, MongoDB</span> <span style="line-height:1.5;">!</span> </div> </div> <p style="line-height:20px;margin:5px auto;font-family:Verdana,Geneva,Arial,Helvetica,sans-serif;font-size:13px;">甚至可以定义javascript函数</p> <div style="border-bottom:#cccccc 1px solid;border-left:#cccccc 1px solid;padding-bottom:5px;line-height:20px;overflow-x:auto;overflow-y:auto;background-color:#f5f5f5;padding-left:5px;padding-right:5px;font-family:'Courier New';word-break:break-all;border-top:#cccccc 1px solid;border-right:#cccccc 1px solid;padding-top:5px;" class="cnblogs_code"> <div> <span style="line-height:1.5;">></span> <span style="line-height:1.5;"> </span> <span style="line-height:1.5;color:#0000ff;">function</span> <span style="line-height:1.5;"> factorial (n) {<br /> ... </span> <span style="line-height:1.5;color:#0000ff;">if</span> <span style="line-height:1.5;"> (n </span> <span style="line-height:1.5;"><=</span> <span style="line-height:1.5;"> </span> <span style="line-height:1.5;">1</span> <span style="line-height:1.5;">) </span> <span style="line-height:1.5;color:#0000ff;">return</span> <span style="line-height:1.5;"> </span> <span style="line-height:1.5;">1</span> <span style="line-height:1.5;">;<br /> ... </span> <span style="line-height:1.5;color:#0000ff;">return</span> <span style="line-height:1.5;"> n </span> <span style="line-height:1.5;">*</span> <span style="line-height:1.5;"> factorial(n </span> <span style="line-height:1.5;">-</span> <span style="line-height:1.5;"> </span> <span style="line-height:1.5;">1</span> <span style="line-height:1.5;">);<br /> ... }<br /> </span> <span style="line-height:1.5;">></span> <span style="line-height:1.5;"> factorial(</span> <span style="line-height:1.5;">5</span> <span style="line-height:1.5;">);<br /> </span> <span style="line-height:1.5;">120</span> </div> </div> <p style="line-height:20px;margin:5px auto;font-family:Verdana,Geneva,Arial,Helvetica,sans-serif;font-size:13px;">能够执行javascript确实很cool，当然这不是shell的全部功能。</p> <ul style="line-height:20px;font-family:Verdana,Geneva,Arial,Helvetica,sans-serif;margin-left:45px;font-size:13px;"> <li>使用use命名切换数据库</li> </ul> <div style="border-bottom:#cccccc 1px solid;border-left:#cccccc 1px solid;padding-bottom:5px;line-height:20px;overflow-x:auto;overflow-y:auto;background-color:#f5f5f5;padding-left:5px;padding-right:5px;font-family:'Courier New';word-break:break-all;border-top:#cccccc 1px solid;border-right:#cccccc 1px solid;padding-top:5px;" class="cnblogs_code"> <div> <span style="line-height:1.5;">></span> <span style="line-height:1.5;"> use foobar<br /> switched to db foobar</span> </div> </div> <p style="line-height:20px;margin:5px auto;font-family:Verdana,Geneva,Arial,Helvetica,sans-serif;font-size:13px;">然后就可以查看db变量来看看当前数据库是啥</p> <div style="border-bottom:#cccccc 1px solid;border-left:#cccccc 1px solid;padding-bottom:5px;line-height:20px;overflow-x:auto;overflow-y:auto;background-color:#f5f5f5;padding-left:5px;padding-right:5px;font-family:'Courier New';word-break:break-all;border-top:#cccccc 1px solid;border-right:#cccccc 1px solid;padding-top:5px;" class="cnblogs_code"> <div> <span style="line-height:1.5;">></span> <span style="line-height:1.5;"> db<br /> foobar</span> </div> </div> <ul style="line-height:20px;font-family:Verdana,Geneva,Arial,Helvetica,sans-serif;margin-left:45px;font-size:13px;"> <li>使用insert函数想collection插入document</li> </ul> <p style="line-height:20px;margin:5px auto;font-family:Verdana,Geneva,Arial,Helvetica,sans-serif;font-size:13px;">先创建一个本地变量叫post</p> <div style="border-bottom:#cccccc 1px solid;border-left:#cccccc 1px solid;padding-bottom:5px;line-height:20px;overflow-x:auto;overflow-y:auto;background-color:#f5f5f5;padding-left:5px;padding-right:5px;font-family:'Courier New';word-break:break-all;border-top:#cccccc 1px solid;border-right:#cccccc 1px solid;padding-top:5px;" class="cnblogs_code"> <div> <span style="line-height:1.5;">></span> <span style="line-height:1.5;"> post </span> <span style="line-height:1.5;">=</span> <span style="line-height:1.5;"> {</span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">title</span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;"> : </span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">My Blog Post</span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">,<br /> ... </span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">content</span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;"> : </span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">Here's my blog post.</span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">,<br /> ... </span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">date</span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;"> : </span> <span style="line-height:1.5;color:#0000ff;">new</span> <span style="line-height:1.5;"> Date()}<br /> {<br /> </span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">title</span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;"> : </span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">My Blog Post</span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">,<br /> </span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">content</span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;"> : </span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">Here's my blog post.</span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">,<br /> </span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">date</span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;"> : </span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">Sat Dec 12 2009 11:23:21 GMT-0500 (EST)</span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;"><br /> }</span> </div> </div> <p style="line-height:20px;margin:5px auto;font-family:Verdana,Geneva,Arial,Helvetica,sans-serif;font-size:13px;">然后把它插入到叫blog的collection里边去</p> <div style="border-bottom:#cccccc 1px solid;border-left:#cccccc 1px solid;padding-bottom:5px;line-height:20px;overflow-x:auto;overflow-y:auto;background-color:#f5f5f5;padding-left:5px;padding-right:5px;font-family:'Courier New';word-break:break-all;border-top:#cccccc 1px solid;border-right:#cccccc 1px solid;padding-top:5px;" class="cnblogs_code"> <div> <span style="line-height:1.5;">></span> <span style="line-height:1.5;"> db.blog.insert(post)</span> </div> </div> <p style="line-height:20px;margin:5px auto;font-family:Verdana,Geneva,Arial,Helvetica,sans-serif;font-size:13px;">然后我们可以用find函数看看blog里边的内容</p> <div style="border-bottom:#cccccc 1px solid;border-left:#cccccc 1px solid;padding-bottom:5px;line-height:20px;overflow-x:auto;overflow-y:auto;background-color:#f5f5f5;padding-left:5px;padding-right:5px;font-family:'Courier New';word-break:break-all;border-top:#cccccc 1px solid;border-right:#cccccc 1px solid;padding-top:5px;" class="cnblogs_code"> <div> <span style="line-height:1.5;">></span> <span style="line-height:1.5;"> db.blog.find()<br /> {<br /> </span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">_id</span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;"> : ObjectId(</span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">4b23c3ca7525f35f94b60a2d</span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">),<br /> </span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">title</span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;"> : </span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">My Blog Post</span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">,<br /> </span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">content</span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;"> : </span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">Here's my blog post.</span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">,<br /> </span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">date</span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;"> : </span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">Sat Dec 12 2009 11:23:21 GMT-0500 (EST)</span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;"><br /> }</span> </div> </div> <p style="line-height:20px;margin:5px auto;font-family:Verdana,Geneva,Arial,Helvetica,sans-serif;font-size:13px;">里边自动加了个叫"_id"的key。</p> <ul style="line-height:20px;font-family:Verdana,Geneva,Arial,Helvetica,sans-serif;margin-left:45px;font-size:13px;"> <li>find返回collection里的书有document，如果只想查看一个使用findone<br /> <div style="border-bottom:#cccccc 1px solid;border-left:#cccccc 1px solid;padding-bottom:5px;overflow-x:auto;overflow-y:auto;background-color:#f5f5f5;padding-left:5px;padding-right:5px;font-family:'Courier New';font-size:12px;word-break:break-all;border-top:#cccccc 1px solid;border-right:#cccccc 1px solid;padding-top:5px;" class="cnblogs_code"> <div> <span style="line-height:1.5;">></span> <span style="line-height:1.5;"> db.blog.findOne()<br /> {<br /> </span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">_id</span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;"> : ObjectId(</span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">4b23c3ca7525f35f94b60a2d</span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">),<br /> </span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">title</span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;"> : </span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">My Blog Post</span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">,<br /> </span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">content</span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;"> : </span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">Here's my blog post.</span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">,<br /> </span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">date</span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;"> : </span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">Sat Dec 12 2009 11:23:21 GMT-0500 (EST)</span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;"><br /> }</span> </div> </div> </li> </ul> <p style="line-height:20px;margin:5px auto;font-family:Verdana,Geneva,Arial,Helvetica,sans-serif;font-size:13px;">find和findone都可以有查询条件，第4章查询里边会讲。</p> <ul style="line-height:20px;font-family:Verdana,Geneva,Arial,Helvetica,sans-serif;margin-left:45px;font-size:13px;"> <li>使用update来更新document</li> </ul> <p style="line-height:20px;margin:5px auto;font-family:Verdana,Geneva,Arial,Helvetica,sans-serif;font-size:13px;">update函数要有至少两个参数，第一个是条件，第二个是新的document</p> <p style="line-height:20px;margin:5px auto;font-family:Verdana,Geneva,Arial,Helvetica,sans-serif;font-size:13px;">先给post变量加一个叫comments的key，给它一个空数组做value。</p> <div style="border-bottom:#cccccc 1px solid;border-left:#cccccc 1px solid;padding-bottom:5px;line-height:20px;overflow-x:auto;overflow-y:auto;background-color:#f5f5f5;padding-left:5px;padding-right:5px;font-family:'Courier New';word-break:break-all;border-top:#cccccc 1px solid;border-right:#cccccc 1px solid;padding-top:5px;" class="cnblogs_code"> <div> <span style="line-height:1.5;">></span> <span style="line-height:1.5;"> post.comments </span> <span style="line-height:1.5;">=</span> <span style="line-height:1.5;"> []<br /> [ ]</span> </div> </div> <p style="line-height:20px;margin:5px auto;font-family:Verdana,Geneva,Arial,Helvetica,sans-serif;font-size:13px;">执行更新，替换掉title是“My Blog Post”的那个document</p> <div style="border-bottom:#cccccc 1px solid;border-left:#cccccc 1px solid;padding-bottom:5px;line-height:20px;overflow-x:auto;overflow-y:auto;background-color:#f5f5f5;padding-left:5px;padding-right:5px;font-family:'Courier New';word-break:break-all;border-top:#cccccc 1px solid;border-right:#cccccc 1px solid;padding-top:5px;" class="cnblogs_code"> <div> <span style="line-height:1.5;">></span> <span style="line-height:1.5;"> db.blog.update({title : </span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">My Blog Post</span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">}, post)</span> </div> </div> <p style="line-height:20px;margin:5px auto;font-family:Verdana,Geneva,Arial,Helvetica,sans-serif;font-size:13px;">看看结果</p> <div style="border-bottom:#cccccc 1px solid;border-left:#cccccc 1px solid;padding-bottom:5px;line-height:20px;overflow-x:auto;overflow-y:auto;background-color:#f5f5f5;padding-left:5px;padding-right:5px;font-family:'Courier New';word-break:break-all;border-top:#cccccc 1px solid;border-right:#cccccc 1px solid;padding-top:5px;" class="cnblogs_code"> <div> <span style="line-height:1.5;">></span> <span style="line-height:1.5;"> db.blog.find()<br /> {<br /> </span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">_id</span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;"> : ObjectId(</span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">4b23c3ca7525f35f94b60a2d</span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">),<br /> </span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">title</span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;"> : </span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">My Blog Post</span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">,<br /> </span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">content</span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;"> : </span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">Here's my blog post.</span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">,<br /> </span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">date</span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;"> : </span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">Sat Dec 12 2009 11:23:21 GMT-0500 (EST)</span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;"><br /> </span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">comments</span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;"> : [ ]<br /> }</span> </div> </div> <ul style="line-height:20px;font-family:Verdana,Geneva,Arial,Helvetica,sans-serif;margin-left:45px;font-size:13px;"> <li>使用remove删除document<br /> <div style="border-bottom:#cccccc 1px solid;border-left:#cccccc 1px solid;padding-bottom:5px;overflow-x:auto;overflow-y:auto;background-color:#f5f5f5;padding-left:5px;padding-right:5px;font-family:'Courier New';font-size:12px;word-break:break-all;border-top:#cccccc 1px solid;border-right:#cccccc 1px solid;padding-top:5px;" class="cnblogs_code"> <div> <span style="line-height:1.5;">></span> <span style="line-height:1.5;"> db.blog.remove({title : </span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">My Blog Post</span> <span style="line-height:1.5;">"</span> <span style="line-height:1.5;">})</span> </div> </div> 现在这个collection就又空了。</li> </ul> <p style="line-height:20px;margin:5px auto;font-family:Verdana,Geneva,Arial,Helvetica,sans-serif;font-size:13px;"><strong>3.基本数据类型</strong></p> <ul style="line-height:20px;font-family:Verdana,Geneva,Arial,Helvetica,sans-serif;margin-left:45px;font-size:13px;"> <li>null<strong><br /> </strong>表示一个空值或者不存在的字段</li> <li>boolean</li> <li>32位整数<br /> shell中无法表示，javascript只支持64位浮点小数，所以会被转化为64位浮点小数。</li> <li>64位整数<br /> 同上</li> <li>64位浮点小数</li> <li>字符串</li> <li>symbol<br /> shell不支持此类型，来自数据库中的symbol类型数据会转化为字符串</li> <li>object id<br /> 0 1 2 3 |4 5 6 |7 8 |9 10 11<br /> Timestamp|Machine | PID |Increment</li> <li>date</li> <li>正则表达式</li> <li>code</li> <li>二进制数据</li> <li>maximum value<br /> bson有这样一个专门的类型来表示可能的最大值，shell不支持此类型。</li> <li>minimum value</li> <li>undefined</li> <li>array</li> <li>embeded document</li> </ul> </div>