第二章、天天生鲜注册功能基本实现
第二章 天天生鲜项目实现基本功能
学习入门指南:
天天生鲜项目搭建文件可从公众号学聚思获取，关注公众号：学聚思、学聚思、学聚思。重要的事情说三遍
本文博客获取关键词：天天生鲜注册实现博客
本项目关键词：天天生鲜注册实现源码
请大家按照关键字搜索哦，另外，本人创建了1个QQ群欢迎各位加入讨论
QQ群号：301666877
天天生鲜项目学习视频
另外如果需要其他资源，比如视频中的工程文档，欢迎公众号留言
本内容持续更新直至天天生鲜项目完成！
本文主要内容：实现注册基本逻辑
本设计不涉及中间过程，直接上手最后的功能，所以自己对着视频分模块学习，把这个整个模块学习完再导入下面的代码
本文中用到的Django的一些说明书
类试图使用手册
章节目录
第一章、天天生鲜项目框架搭建
第二章、天天生鲜注册功能实现
第一步
首先将static文件夹下面的register.html复制到templates中，由于CSS文件以及js文件与其不在同一路径，我们需要将头文件做如下改变
# 将头部文件做如下改变 PS:这个注释最好不要复制进去
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
"http://www.w3.org/1999/xhtml" xml:lang="en">
{% load static %}
-equiv="Content-Type" content="text/html;charset=UTF-8">
天天生鲜<span class="token operator">-</span>注册<<span class="token operator">/</span>title>
<link rel=<span class="token string">"stylesheet"</span> <span class="token function">type</span>=<span class="token string">"text/css"</span> href=<span class="token string">"{% static 'css/reset.css' %}"</span>>
<link rel=<span class="token string">"stylesheet"</span> <span class="token function">type</span>=<span class="token string">"text/css"</span> href=<span class="token string">"{% static 'css/main.css' %}"</span>>
<script <span class="token function">type</span>=<span class="token string">"text/javascript"</span> src=<span class="token string">"{% static js/jquery-1.12.4.min.js %}"</span>><<span class="token operator">/</span>script>
<script <span class="token function">type</span>=<span class="token string">"text/javascript"</span> src=<span class="token string">"{% static 'js/register.js' %}"</span>><<span class="token operator">/</span>script>
<<span class="token operator">/</span>head>
</code></pre>
<p>另外，如果前端代码中，存在图片连接，由于图片存放在static中，因此图片也需要做如下改变，只要是图片连接都要做这种改变</p>
<pre><code class="prism language-powershell"><a <span class="token keyword">class</span>=<span class="token string">"reg_logo"</span>><img src=<span class="token string">"{% static 'images/logo02.png' %}"</span>><<span class="token operator">/</span>a>
</code></pre>
<p>最后我们的前端页面register.html中的是这样的，当然中间还存在很多改变，自己看视频，防止敲错，直接复制即可</p>
<pre><code class="prism language-html"><span class="token doctype"><!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>html</span> <span class="token attr-name">xmlns</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>http://www.w3.org/1999/xhtml<span class="token punctuation">"</span></span> <span class="token attr-name"><span class="token namespace">xml:</span>lang</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>en<span class="token punctuation">"</span></span><span class="token punctuation">></span></span>
{% load static %}
<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>head</span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>meta</span> <span class="token attr-name">http-equiv</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>Content-Type<span class="token punctuation">"</span></span> <span class="token attr-name">content</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>text/html;charset=UTF-8<span class="token punctuation">"</span></span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>title</span><span class="token punctuation">></span></span>天天生鲜-注册<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>title</span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>link</span> <span class="token attr-name">rel</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>stylesheet<span class="token punctuation">"</span></span> <span class="token attr-name">type</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>text/css<span class="token punctuation">"</span></span> <span class="token attr-name">href</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>{% static <span class="token punctuation">'</span>css/reset.css<span class="token punctuation">'</span> %}<span class="token punctuation">"</span></span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>link</span> <span class="token attr-name">rel</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>stylesheet<span class="token punctuation">"</span></span> <span class="token attr-name">type</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>text/css<span class="token punctuation">"</span></span> <span class="token attr-name">href</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>{% static <span class="token punctuation">'</span>css/main.css<span class="token punctuation">'</span> %}<span class="token punctuation">"</span></span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>script</span> <span class="token attr-name">type</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>text/javascript<span class="token punctuation">"</span></span> <span class="token attr-name">src</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>{% static <span class="token punctuation">'</span>js/jquery-1.12.4.min.js<span class="token punctuation">'</span> %}<span class="token punctuation">"</span></span><span class="token punctuation">></span></span><span class="token script language-javascript"></span><span class="token tag"><span class="token tag"><span class="token punctuation"></</span>script</span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>script</span> <span class="token attr-name">type</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>text/javascript<span class="token punctuation">"</span></span> <span class="token attr-name">src</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>{% static <span class="token punctuation">'</span>js/register.js<span class="token punctuation">'</span> %}<span class="token punctuation">"</span></span><span class="token punctuation">></span></span><span class="token script language-javascript"></span><span class="token tag"><span class="token tag"><span class="token punctuation"></</span>script</span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>head</span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>body</span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>div</span> <span class="token attr-name">class</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>register_con<span class="token punctuation">"</span></span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>div</span> <span class="token attr-name">class</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>l_con fl<span class="token punctuation">"</span></span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>a</span> <span class="token attr-name">class</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>reg_logo<span class="token punctuation">"</span></span><span class="token punctuation">></span></span><span class="token tag"><span class="token tag"><span class="token punctuation"><</span>a</span> <span class="token attr-name">class</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>reg_logo<span class="token punctuation">"</span></span><span class="token punctuation">></span></span><span class="token tag"><span class="token tag"><span class="token punctuation"><</span>img</span> <span class="token attr-name">src</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>{% static <span class="token punctuation">'</span>images/logo02.png<span class="token punctuation">'</span> %}<span class="token punctuation">"</span></span><span class="token punctuation">></span></span><span class="token tag"><span class="token tag"><span class="token punctuation"></</span>a</span><span class="token punctuation">></span></span><span class="token tag"><span class="token tag"><span class="token punctuation"></</span>a</span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>div</span> <span class="token attr-name">class</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>reg_slogan<span class="token punctuation">"</span></span><span class="token punctuation">></span></span>足不出户 · 新鲜每一天<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>div</span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>div</span> <span class="token attr-name">class</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>reg_banner<span class="token punctuation">"</span></span><span class="token punctuation">></span></span><span class="token tag"><span class="token tag"><span class="token punctuation"></</span>div</span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>div</span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>div</span> <span class="token attr-name">class</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>r_con fr<span class="token punctuation">"</span></span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>div</span> <span class="token attr-name">class</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>reg_title clearfix<span class="token punctuation">"</span></span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>h1</span><span class="token punctuation">></span></span>用户注册<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>h1</span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>a</span> <span class="token attr-name">href</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>#<span class="token punctuation">"</span></span><span class="token punctuation">></span></span>登录<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>a</span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>div</span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>div</span> <span class="token attr-name">class</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>reg_form clearfix<span class="token punctuation">"</span></span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>form</span> <span class="token attr-name">method</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>post<span class="token punctuation">"</span></span> <span class="token attr-name">action</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>/user/register<span class="token punctuation">"</span></span><span class="token punctuation">></span></span>
{% csrf_token %}
<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>ul</span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>li</span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>label</span><span class="token punctuation">></span></span>用户名:<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>label</span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>input</span> <span class="token attr-name">type</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>text<span class="token punctuation">"</span></span> <span class="token attr-name">name</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>user_name<span class="token punctuation">"</span></span> <span class="token attr-name">id</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>user_name<span class="token punctuation">"</span></span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>span</span> <span class="token attr-name">class</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>error_tip<span class="token punctuation">"</span></span><span class="token punctuation">></span></span>提示信息<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>span</span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>li</span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>li</span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>label</span><span class="token punctuation">></span></span>密码:<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>label</span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>input</span> <span class="token attr-name">type</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>password<span class="token punctuation">"</span></span> <span class="token attr-name">name</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>pwd<span class="token punctuation">"</span></span> <span class="token attr-name">id</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>pwd<span class="token punctuation">"</span></span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>span</span> <span class="token attr-name">class</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>error_tip<span class="token punctuation">"</span></span><span class="token punctuation">></span></span>提示信息<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>span</span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>li</span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>li</span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>label</span><span class="token punctuation">></span></span>确认密码:<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>label</span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>input</span> <span class="token attr-name">type</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>password<span class="token punctuation">"</span></span> <span class="token attr-name">name</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>cpwd<span class="token punctuation">"</span></span> <span class="token attr-name">id</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>cpwd<span class="token punctuation">"</span></span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>span</span> <span class="token attr-name">class</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>error_tip<span class="token punctuation">"</span></span><span class="token punctuation">></span></span>提示信息<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>span</span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>li</span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>li</span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>label</span><span class="token punctuation">></span></span>邮箱:<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>label</span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>input</span> <span class="token attr-name">type</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>text<span class="token punctuation">"</span></span> <span class="token attr-name">name</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>email<span class="token punctuation">"</span></span> <span class="token attr-name">id</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>email<span class="token punctuation">"</span></span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>span</span> <span class="token attr-name">class</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>error_tip<span class="token punctuation">"</span></span><span class="token punctuation">></span></span>提示信息<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>span</span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>li</span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>li</span> <span class="token attr-name">class</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>agreement<span class="token punctuation">"</span></span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>input</span> <span class="token attr-name">type</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>checkbox<span class="token punctuation">"</span></span> <span class="token attr-name">name</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>allow<span class="token punctuation">"</span></span> <span class="token attr-name">id</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>allow<span class="token punctuation">"</span></span> <span class="token attr-name">checked</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>checked<span class="token punctuation">"</span></span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>label</span><span class="token punctuation">></span></span>同意”天天生鲜用户使用协议“<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>label</span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>span</span> <span class="token attr-name">class</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>error_tip2<span class="token punctuation">"</span></span><span class="token punctuation">></span></span>提示信息<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>span</span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>li</span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>li</span> <span class="token attr-name">class</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>reg_sub<span class="token punctuation">"</span></span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>input</span> <span class="token attr-name">type</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>submit<span class="token punctuation">"</span></span> <span class="token attr-name">value</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>注 册<span class="token punctuation">"</span></span> <span class="token attr-name">name</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span><span class="token punctuation">"</span></span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>li</span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>ul</span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>form</span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>div</span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>div</span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>div</span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>div</span> <span class="token attr-name">class</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>footer no-mp<span class="token punctuation">"</span></span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>div</span> <span class="token attr-name">class</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>foot_link<span class="token punctuation">"</span></span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>a</span> <span class="token attr-name">href</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>#<span class="token punctuation">"</span></span><span class="token punctuation">></span></span>关于我们<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>a</span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>span</span><span class="token punctuation">></span></span>|<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>span</span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>a</span> <span class="token attr-name">href</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>#<span class="token punctuation">"</span></span><span class="token punctuation">></span></span>联系我们<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>a</span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>span</span><span class="token punctuation">></span></span>|<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>span</span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>a</span> <span class="token attr-name">href</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>#<span class="token punctuation">"</span></span><span class="token punctuation">></span></span>招聘人才<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>a</span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>span</span><span class="token punctuation">></span></span>|<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>span</span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>a</span> <span class="token attr-name">href</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>#<span class="token punctuation">"</span></span><span class="token punctuation">></span></span>友情链接<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>a</span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>div</span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>p</span><span class="token punctuation">></span></span>CopyRight © 2016 北京天天生鲜信息技术有限公司 All Rights Reserved<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>p</span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>p</span><span class="token punctuation">></span></span>电话：010-****888 京ICP备*******8号<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>p</span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>div</span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>body</span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>html</span><span class="token punctuation">></span></span>
</code></pre>
<p>然后再user/views.py中添加如下代码</p>
<pre><code class="prism language-powershell"><span class="token keyword">from</span> django<span class="token punctuation">.</span>shortcuts import render<span class="token punctuation">,</span>redirect
<span class="token keyword">from</span> django<span class="token punctuation">.</span>urls import reverse <span class="token comment">#反向解析函数</span>
<span class="token keyword">from</span> django<span class="token punctuation">.</span>core<span class="token punctuation">.</span>mail import send_mail <span class="token comment">#导入发送邮件函数</span>
<span class="token keyword">from</span> django<span class="token punctuation">.</span>views<span class="token punctuation">.</span>generic import View <span class="token comment">#导入类视图</span>
<span class="token keyword">from</span> django<span class="token punctuation">.</span>http import HttpResponse
<span class="token keyword">from</span> django<span class="token punctuation">.</span>conf import settings
<span class="token keyword">from</span> user<span class="token punctuation">.</span>models import User
<span class="token keyword">from</span> itsdangerous import TimedJSONWebSignatureSerializer as Serializer <span class="token comment">#导入用于用户信息加密的插件并且给它取个别名为Serializer</span>
<span class="token keyword">from</span> itsdangerous import SignatureExpired <span class="token comment">#导入异常</span>
import re <span class="token comment">#导入正则匹配模块用于检验邮箱</span>
<span class="token comment"># Create your views here.</span>
<span class="token keyword">class</span> RegisterView<span class="token punctuation">(</span>View<span class="token punctuation">)</span>:
<span class="token string">"'注册类试图'"</span>
def get<span class="token punctuation">(</span>self<span class="token punctuation">,</span>request<span class="token punctuation">)</span>:
<span class="token string">"'显示注册页面'"</span>
<span class="token keyword">return</span> render<span class="token punctuation">(</span>request<span class="token punctuation">,</span> <span class="token string">'register.html'</span><span class="token punctuation">)</span>
def post<span class="token punctuation">(</span>self<span class="token punctuation">,</span>request<span class="token punctuation">)</span>:
<span class="token string">"'进行注册处理'"</span>
<span class="token comment"># 接收数据</span>
username = request<span class="token punctuation">.</span>POST<span class="token punctuation">.</span>get<span class="token punctuation">(</span><span class="token string">'user_name'</span><span class="token punctuation">)</span>
password = request<span class="token punctuation">.</span>POST<span class="token punctuation">.</span>get<span class="token punctuation">(</span><span class="token string">'pwd'</span><span class="token punctuation">)</span>
email = request<span class="token punctuation">.</span>POST<span class="token punctuation">.</span>get<span class="token punctuation">(</span><span class="token string">'email'</span><span class="token punctuation">)</span>
allow = request<span class="token punctuation">.</span>POST<span class="token punctuation">.</span>get<span class="token punctuation">(</span><span class="token string">'allow'</span><span class="token punctuation">)</span>
<span class="token comment"># 进行数据校验</span>
<span class="token keyword">if</span> not all<span class="token punctuation">(</span><span class="token namespace">[username, password, email]</span><span class="token punctuation">)</span>:
<span class="token comment"># 数据不完整</span>
<span class="token keyword">return</span> render<span class="token punctuation">(</span>request<span class="token punctuation">,</span> <span class="token string">'register.html'</span><span class="token punctuation">,</span> <span class="token punctuation">{</span><span class="token string">'errmsg'</span>: <span class="token string">'数据不完整'</span><span class="token punctuation">}</span><span class="token punctuation">)</span>
<span class="token comment"># 检验邮箱</span>
<span class="token comment"># 如果不是一个邮箱，即邮箱形式不合法</span>
<span class="token keyword">if</span> not re<span class="token punctuation">.</span>match<span class="token punctuation">(</span>r<span class="token string">'^[a-z0-9][\w.\-]*@[a-z0-9\-]+(\.[a-z]{2,5}){1,2}$'</span><span class="token punctuation">,</span> email<span class="token punctuation">)</span>:
<span class="token comment"># 邮箱格式不正确</span>
<span class="token keyword">return</span> render<span class="token punctuation">(</span>request<span class="token punctuation">,</span> <span class="token string">'register.html'</span><span class="token punctuation">,</span> <span class="token punctuation">{</span><span class="token string">'errmsg'</span>: <span class="token string">'邮箱不合法'</span><span class="token punctuation">}</span><span class="token punctuation">)</span>
<span class="token keyword">if</span> allow <span class="token operator">!</span>= <span class="token string">'on'</span>:
<span class="token comment"># 是否同意协议</span>
<span class="token keyword">return</span> render<span class="token punctuation">(</span>request<span class="token punctuation">,</span> <span class="token string">'register.html'</span><span class="token punctuation">,</span> <span class="token punctuation">{</span><span class="token string">'errmsg'</span>: <span class="token string">'请同意协议'</span><span class="token punctuation">}</span><span class="token punctuation">)</span>
<span class="token comment"># 校验用户名是否重复</span>
<span class="token keyword">try</span>:
user= User<span class="token punctuation">.</span>objects<span class="token punctuation">.</span>get<span class="token punctuation">(</span>username=username<span class="token punctuation">)</span>
except User<span class="token punctuation">.</span>DoesNotExist:
user = None
<span class="token keyword">if</span> user:
<span class="token comment"># 用户名已存在</span>
<span class="token keyword">return</span> render<span class="token punctuation">(</span>request<span class="token punctuation">,</span> <span class="token string">'register.html'</span><span class="token punctuation">,</span> <span class="token punctuation">{</span><span class="token string">'errmsg'</span>: <span class="token string">'用户名已存在'</span><span class="token punctuation">}</span><span class="token punctuation">)</span>
<span class="token comment"># 进行业务处理：进行用户注册</span>
user = User<span class="token punctuation">.</span>objects<span class="token punctuation">.</span>create_user<span class="token punctuation">(</span>username<span class="token punctuation">,</span> email<span class="token punctuation">,</span> password<span class="token punctuation">)</span>
user<span class="token punctuation">.</span>is_active = 0 <span class="token comment"># 不让他自动激活</span>
user<span class="token punctuation">.</span>save<span class="token punctuation">(</span><span class="token punctuation">)</span>
<span class="token comment">#发送激活邮件，包含激活链接：</span>
<span class="token comment">#激活连接中需要包含用户的身份信息，并且要把身份信息进行加密</span>
<span class="token comment">#加密用户的身份信息，生成激活token</span>
serializer=Serializer<span class="token punctuation">(</span>settings<span class="token punctuation">.</span>SECRET_KEY<span class="token punctuation">,</span>3600<span class="token punctuation">)</span>
info=<span class="token punctuation">{</span><span class="token string">'confirm'</span>:user<span class="token punctuation">.</span>id<span class="token punctuation">}</span>
token=serializer<span class="token punctuation">.</span>dumps<span class="token punctuation">(</span>info<span class="token punctuation">)</span> <span class="token comment">#返回的是字节</span>
token=token<span class="token punctuation">.</span>decode<span class="token punctuation">(</span><span class="token punctuation">)</span> <span class="token comment">#进行字节解码</span>
<span class="token comment"># 组织邮件信息</span>
subject = <span class="token string">'天天生鲜欢迎信息'</span>
message = <span class="token string">'欢迎注册'</span>
sender = settings<span class="token punctuation">.</span>EMAIL_FROM <span class="token comment"># 发件人</span>
receiver = <span class="token namespace">[email]</span>
html_message = <span class="token string">'<h1>%s欢迎您成为为天天生鲜交易市场注册会员</h1>请点击下面链接激活您的账户<br/><a href="http://127.0.0.1:8000/user/active/%s">http://127.0.0.1:8000/user/active/%s</a>'</span> <span class="token operator">%</span> <span class="token punctuation">(</span>username<span class="token punctuation">,</span> token<span class="token punctuation">,</span> token<span class="token punctuation">)</span>
send_mail<span class="token punctuation">(</span>subject<span class="token punctuation">,</span> message<span class="token punctuation">,</span> sender<span class="token punctuation">,</span> receiver<span class="token punctuation">,</span> html_message=html_message<span class="token punctuation">)</span>
<span class="token comment"># 返回应答，跳转到首页</span>
<span class="token keyword">return</span> redirect<span class="token punctuation">(</span>reverse<span class="token punctuation">(</span><span class="token string">'goods:index'</span><span class="token punctuation">)</span><span class="token punctuation">)</span>
<span class="token keyword">class</span> ActiveView<span class="token punctuation">(</span>View<span class="token punctuation">)</span>:
<span class="token string">"'用户激活'"</span>
def get<span class="token punctuation">(</span>self<span class="token punctuation">,</span>request<span class="token punctuation">,</span>token<span class="token punctuation">)</span>:
<span class="token string">"'进行用户激活'"</span>
<span class="token comment"># 解密参数，获取要激活的用户信息</span>
serializer = Serializer<span class="token punctuation">(</span>settings<span class="token punctuation">.</span>SECRET_KEY<span class="token punctuation">,</span> 3600<span class="token punctuation">)</span>
<span class="token keyword">try</span>:
info=serializer<span class="token punctuation">.</span>loads<span class="token punctuation">(</span>token<span class="token punctuation">)</span>
<span class="token comment">#获取待激活用户的id</span>
user_id=info<span class="token punctuation">[</span><span class="token string">'confirm'</span><span class="token punctuation">]</span>
<span class="token comment">#根据用户id获取用户信息</span>
user=User<span class="token punctuation">.</span>objects<span class="token punctuation">.</span>get<span class="token punctuation">(</span>id=user_id<span class="token punctuation">)</span>
user<span class="token punctuation">.</span>is_active=1
user<span class="token punctuation">.</span>save<span class="token punctuation">(</span><span class="token punctuation">)</span>
<span class="token comment">#跳转登录页面</span>
<span class="token keyword">return</span> redirect<span class="token punctuation">(</span>reverse<span class="token punctuation">(</span><span class="token string">'user:login'</span><span class="token punctuation">)</span><span class="token punctuation">)</span>
except SignatureExpired as e:
<span class="token comment">#激活链接已过期</span>
<span class="token keyword">return</span> HttpResponse<span class="token punctuation">(</span><span class="token string">'激活链接已过期'</span><span class="token punctuation">)</span>
</code></pre>
<p>然后在user/urls.py中添加如下内容太</p>
<pre><code class="prism language-powershell"><span class="token keyword">from</span> django<span class="token punctuation">.</span>urls import path<span class="token punctuation">,</span>re_path
<span class="token keyword">from</span> user<span class="token punctuation">.</span>views import RegisterView<span class="token punctuation">,</span>ActiveView
urlpatterns = <span class="token punctuation">[</span>
path<span class="token punctuation">(</span><span class="token string">'register'</span><span class="token punctuation">,</span>RegisterView<span class="token punctuation">.</span>as_view<span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">,</span>name=<span class="token string">'register'</span><span class="token punctuation">)</span><span class="token punctuation">,</span> <span class="token comment">#注册</span>
re_path<span class="token punctuation">(</span><span class="token string">'active/(?P<token>.*)$'</span><span class="token punctuation">,</span>ActiveView<span class="token punctuation">.</span>as_view<span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">,</span>name=<span class="token string">'active'</span><span class="token punctuation">)</span><span class="token punctuation">,</span> <span class="token comment">#用户激活</span>
<span class="token punctuation">]</span>
</code></pre>
<p>由于可能用到首页，所以在goods/urls.py中添加如下内容：</p>
<pre><code class="prism language-powershell"><span class="token keyword">from</span> django<span class="token punctuation">.</span>urls import path
<span class="token keyword">from</span> goods import views
urlpatterns = <span class="token punctuation">[</span>
path<span class="token punctuation">(</span><span class="token string">''</span><span class="token punctuation">,</span>views<span class="token punctuation">.</span>index<span class="token punctuation">,</span>name=<span class="token string">'index'</span><span class="token punctuation">)</span><span class="token punctuation">,</span> <span class="token comment">#首页</span>
<span class="token punctuation">]</span>
</code></pre>
<p>在goods/views.py中添加如下内容</p>
<pre><code class="prism language-powershell"><span class="token keyword">from</span> django<span class="token punctuation">.</span>shortcuts import render
<span class="token comment"># Create your views here.</span>
def index<span class="token punctuation">(</span>request<span class="token punctuation">)</span>:
<span class="token string">"'首页'"</span>
<span class="token keyword">return</span> render<span class="token punctuation">(</span>request<span class="token punctuation">,</span><span class="token string">'index.html'</span><span class="token punctuation">)</span>
</code></pre>
<h5>第二步、一些插件的安装</h5>
<p>发送邮件时，为了对有些链接进行加密，我们需要安装加密插件"itsdangerous"，直接运行：</p>
<pre><code class="prism language-powershell">pip install itsdangerous <span class="token comment">#第一步安装插件</span>
<span class="token keyword">from</span> itsdangerous import TimedJSONWebSignatureSerializer as Serializer <span class="token comment">#第二步 在user/views.py导入这个</span>
<span class="token comment"># 第三步，在settings中做如下配置,记得看视频改成自己的邮箱配置啊！</span>
<span class="token comment"># 发送邮件配置 </span>
EMAIL_BACKEND = <span class="token string">'django.core.mail.backends.smtp.EmailBackend'</span>
<span class="token comment"># smpt服务地址</span>
EMAIL_HOST = <span class="token string">'smtp.163.com'</span>
EMAIL_PORT = 25
<span class="token comment"># 发送邮件的邮箱</span>
EMAIL_HOST_USER = <span class="token string">'smartli_it@163.com'</span>
<span class="token comment"># 在邮箱中设置的客户端授权密码</span>
EMAIL_HOST_PASSWORD = <span class="token string">'smartli123'</span>
<span class="token comment"># 收件人看到的发件人</span>
EMAIL_FROM = <span class="token string">'天天生鲜<smartli_it@163.com>'</span>
</code></pre>
<p>mysql数据库应用小技巧</p>
<pre><code class="prism language-mysql"># 1、如何删除数据库中某个表中的数据，比如从df_user表中删除id=1的用户
delete from df_user where id=1
# 2、查看df_user表中的全部数据
select * from df_user;
select * from df_user \G; #这个可以让数据一行行的展示
# 3、如何查看表的结构,比如df_user表
desc df_user;
</code></pre>
<hr>
</div>
</div>
</div>
</div>
</div>
<!--PC和WAP自适应版-->
<div id="SOHUCS" sid="1642560743230464000"></div>
<script type="text/javascript" src="/views/front/js/chanyan.js"></script>
<!-- 文章页-底部 动态广告位 -->
<div class="youdao-fixed-ad" id="detail_ad_bottom"></div>
</div>
<div class="col-md-3">
<div class="row" id="ad">
<!-- 文章页-右侧1 动态广告位 -->
<div id="right-1" class="col-lg-12 col-md-12 col-sm-4 col-xs-4 ad">
<div class="youdao-fixed-ad" id="detail_ad_1"> </div>
</div>
<!-- 文章页-右侧2 动态广告位 -->
<div id="right-2" class="col-lg-12 col-md-12 col-sm-4 col-xs-4 ad">
<div class="youdao-fixed-ad" id="detail_ad_2"></div>
</div>
<!-- 文章页-右侧3 动态广告位 -->
<div id="right-3" class="col-lg-12 col-md-12 col-sm-4 col-xs-4 ad">
<div class="youdao-fixed-ad" id="detail_ad_3"></div>
</div>
</div>
</div>
</div>
</div>
</div>
<div class="container">
<h4 class="pt20 mb15 mt0 border-top">你可能感兴趣的:(python,数据库,django)</h4>
<div id="paradigm-article-related">
<div class="recommend-post mb30">
<ul class="widget-links">
<li><a href="/article/1835511912843014144.htm"
title="理解Gunicorn：Python WSGI服务器的基石" target="_blank">理解Gunicorn：Python WSGI服务器的基石</a>
<span class="text-muted">范范0825</span>
<a class="tag" taget="_blank" href="/search/ipython/1.htm">ipython</a><a class="tag" taget="_blank" href="/search/linux/1.htm">linux</a><a class="tag" taget="_blank" href="/search/%E8%BF%90%E7%BB%B4/1.htm">运维</a>
<div>理解Gunicorn：PythonWSGI服务器的基石介绍Gunicorn，全称GreenUnicorn，是一个为PythonWSGI（WebServerGatewayInterface）应用设计的高效、轻量级HTTP服务器。作为PythonWeb应用部署的常用工具，Gunicorn以其高性能和易用性著称。本文将介绍Gunicorn的基本概念、安装和配置，帮助初学者快速上手。1.什么是Gunico</div>
</li>
<li><a href="/article/1835506869838376960.htm"
title="Python数据分析与可视化实战指南" target="_blank">Python数据分析与可视化实战指南</a>
<span class="text-muted">William数据分析</span>
<a class="tag" taget="_blank" href="/search/python/1.htm">python</a><a class="tag" taget="_blank" href="/search/python/1.htm">python</a><a class="tag" taget="_blank" href="/search/%E6%95%B0%E6%8D%AE/1.htm">数据</a>
<div>在数据驱动的时代，Python因其简洁的语法、强大的库生态系统以及活跃的社区，成为了数据分析与可视化的首选语言。本文将通过一个详细的案例，带领大家学习如何使用Python进行数据分析，并通过可视化来直观呈现分析结果。一、环境准备1.1安装必要库在开始数据分析和可视化之前，我们需要安装一些常用的库。主要包括pandas、numpy、matplotlib和seaborn等。这些库分别用于数据处理、数学</div>
</li>
<li><a href="/article/1835505858939809792.htm"
title="python os.environ" target="_blank">python os.environ</a>
<span class="text-muted">江湖偌大</span>
<a class="tag" taget="_blank" href="/search/python/1.htm">python</a><a class="tag" taget="_blank" href="/search/%E6%B7%B1%E5%BA%A6%E5%AD%A6%E4%B9%A0/1.htm">深度学习</a>
<div>os.environ['TF_CPP_MIN_LOG_LEVEL']='0'#默认值，输出所有信息os.environ['TF_CPP_MIN_LOG_LEVEL']='1'#屏蔽通知信息（INFO）os.environ['TF_CPP_MIN_LOG_LEVEL']='2'#屏蔽通知信息和警告信息（INFO\WARNING）os.environ['TF_CPP_MIN_LOG_LEVEL']='</div>
</li>
<li><a href="/article/1835505606245576704.htm"
title="Python中os.environ基本介绍及使用方法" target="_blank">Python中os.environ基本介绍及使用方法</a>
<span class="text-muted">鹤冲天Pro</span>
<a class="tag" taget="_blank" href="/search/%23/1.htm">#</a><a class="tag" taget="_blank" href="/search/Python/1.htm">Python</a><a class="tag" taget="_blank" href="/search/python/1.htm">python</a><a class="tag" taget="_blank" href="/search/%E6%9C%8D%E5%8A%A1%E5%99%A8/1.htm">服务器</a><a class="tag" taget="_blank" href="/search/%E5%BC%80%E5%8F%91%E8%AF%AD%E8%A8%80/1.htm">开发语言</a>
<div>文章目录python中os.environos.environ简介os.environ进行环境变量的增删改查python中os.environ的使用详解1.简介2.key字段详解2.1常见key字段3.os.environ.get()用法4.环境变量的增删改查和判断是否存在4.1新增环境变量4.2更新环境变量4.3获取环境变量4.4删除环境变量4.5判断环境变量是否存在python中os.envi</div>
</li>
<li><a href="/article/1835505226933694464.htm"
title="Pyecharts数据可视化大屏：打造沉浸式数据分析体验" target="_blank">Pyecharts数据可视化大屏：打造沉浸式数据分析体验</a>
<span class="text-muted">我的运维人生</span>
<a class="tag" taget="_blank" href="/search/%E4%BF%A1%E6%81%AF%E5%8F%AF%E8%A7%86%E5%8C%96/1.htm">信息可视化</a><a class="tag" taget="_blank" href="/search/%E6%95%B0%E6%8D%AE%E5%88%86%E6%9E%90/1.htm">数据分析</a><a class="tag" taget="_blank" href="/search/%E6%95%B0%E6%8D%AE%E6%8C%96%E6%8E%98/1.htm">数据挖掘</a><a class="tag" taget="_blank" href="/search/%E8%BF%90%E7%BB%B4%E5%BC%80%E5%8F%91/1.htm">运维开发</a><a class="tag" taget="_blank" href="/search/%E6%8A%80%E6%9C%AF%E5%85%B1%E4%BA%AB/1.htm">技术共享</a>
<div>Pyecharts数据可视化大屏：打造沉浸式数据分析体验在当今这个数据驱动的时代，如何将海量数据以直观、生动的方式展现出来，成为了数据分析师和企业决策者关注的焦点。Pyecharts，作为一款基于Python的开源数据可视化库，凭借其丰富的图表类型、灵活的配置选项以及高度的定制化能力，成为了构建数据可视化大屏的理想选择。本文将深入探讨如何利用Pyecharts打造数据可视化大屏，并通过实际代码案例</div>
</li>
<li><a href="/article/1835504217729626112.htm"
title="Python教程：一文了解使用Python处理XPath" target="_blank">Python教程：一文了解使用Python处理XPath</a>
<span class="text-muted">旦莫</span>
<a class="tag" taget="_blank" href="/search/Python%E8%BF%9B%E9%98%B6/1.htm">Python进阶</a><a class="tag" taget="_blank" href="/search/python/1.htm">python</a><a class="tag" taget="_blank" href="/search/%E5%BC%80%E5%8F%91%E8%AF%AD%E8%A8%80/1.htm">开发语言</a>
<div>目录1.环境准备1.1安装lxml1.2验证安装2.XPath基础2.1什么是XPath？2.2XPath语法2.3示例XML文档3.使用lxml解析XML3.1解析XML文档3.2查看解析结果4.XPath查询4.1基本路径查询4.2使用属性查询4.3查询多个节点5.XPath的高级用法5.1使用逻辑运算符5.2使用函数6.实战案例6.1从网页抓取数据6.1.1安装Requests库6.1.2代</div>
</li>
<li><a href="/article/1835504218178416640.htm"
title="Google earth studio 简介" target="_blank">Google earth studio 简介</a>
<span class="text-muted">陟彼高冈yu</span>
<a class="tag" taget="_blank" href="/search/%E6%97%85%E6%B8%B8/1.htm">旅游</a>
<div>GoogleEarthStudio是一个基于Web的动画工具，专为创作使用GoogleEarth数据的动画和视频而设计。它利用了GoogleEarth强大的三维地图和卫星影像数据库，使用户能够轻松地创建逼真的地球动画、航拍视频和动态地图可视化。网址为https://www.google.com/earth/studio/。GoogleEarthStudio是一个基于Web的动画工具，专为创作使用G</div>
</li>
<li><a href="/article/1835503965563875328.htm"
title="python os.environ_python os.environ 读取和设置环境变量" target="_blank">python os.environ_python os.environ 读取和设置环境变量</a>
<span class="text-muted">weixin_39605414</span>
<a class="tag" taget="_blank" href="/search/python/1.htm">python</a><a class="tag" taget="_blank" href="/search/os.environ/1.htm">os.environ</a>
<div>>>>importos>>>os.environ.keys()['LC_NUMERIC','GOPATH','GOROOT','GOBIN','LESSOPEN','SSH_CLIENT','LOGNAME','USER','HOME','LC_PAPER','PATH','DISPLAY','LANG','TERM','SHELL','J2REDIR','LC_MONETARY','QT_QPA</div>
</li>
<li><a href="/article/1835501821569888256.htm"
title="关于提高复杂业务逻辑代码可读性的思考" target="_blank">关于提高复杂业务逻辑代码可读性的思考</a>
<span class="text-muted">编程经验分享</span>
<a class="tag" taget="_blank" href="/search/%E5%BC%80%E5%8F%91%E7%BB%8F%E9%AA%8C/1.htm">开发经验</a><a class="tag" taget="_blank" href="/search/java/1.htm">java</a><a class="tag" taget="_blank" href="/search/%E6%95%B0%E6%8D%AE%E5%BA%93/1.htm">数据库</a><a class="tag" taget="_blank" href="/search/%E5%BC%80%E5%8F%91%E8%AF%AD%E8%A8%80/1.htm">开发语言</a>
<div>目录前言需求场景常规写法拆分方法领域对象总结前言实际工作中大部分时间都是在写业务逻辑，一般都是三层架构，表示层（Controller）接收客户端请求，并对入参做检验，业务逻辑层（Service）负责处理业务逻辑，一般开发都是在这一层中写具体的业务逻辑。数据访问层（Dao）是直接和数据库交互的，用于查数据给业务逻辑层，或者是将业务逻辑层处理后的数据写入数据库。简单的增删改查接口不用多说，基本上写好一</div>
</li>
<li><a href="/article/1835499681732456448.htm"
title="SQL Server_查询某一数据库中的所有表的内容" target="_blank">SQL Server_查询某一数据库中的所有表的内容</a>
<span class="text-muted">qq_42772833</span>
<a class="tag" taget="_blank" href="/search/SQL/1.htm">SQL</a><a class="tag" taget="_blank" href="/search/Server/1.htm">Server</a><a class="tag" taget="_blank" href="/search/%E6%95%B0%E6%8D%AE%E5%BA%93/1.htm">数据库</a><a class="tag" taget="_blank" href="/search/sqlserver/1.htm">sqlserver</a>
<div>1.查看所有表的表名要列出CrabFarmDB数据库中的所有表（名），可以使用以下SQL语句：USECrabFarmDB;--切换到目标数据库GOSELECTTABLE_NAMEFROMINFORMATION_SCHEMA.TABLESWHERETABLE_TYPE='BASETABLE';对这段SQL脚本的解释：SELECTTABLE_NAME：这个语句的作用是从查询结果中选择TABLE_NAM</div>
</li>
<li><a href="/article/1835497664922349568.htm"
title="使用Faiss进行高效相似度搜索" target="_blank">使用Faiss进行高效相似度搜索</a>
<span class="text-muted">llzwxh888</span>
<a class="tag" taget="_blank" href="/search/faiss/1.htm">faiss</a><a class="tag" taget="_blank" href="/search/python/1.htm">python</a>
<div>在现代AI应用中，快速和高效的相似度搜索是至关重要的。Faiss（FacebookAISimilaritySearch）是一个专门用于快速相似度搜索和聚类的库，特别适用于高维向量。本文将介绍如何使用Faiss来进行相似度搜索，并结合Python代码演示其基本用法。什么是Faiss？Faiss是一个由FacebookAIResearch团队开发的开源库，主要用于高维向量的相似性搜索和聚类。Faiss</div>
</li>
<li><a href="/article/1835497665853485056.htm"
title="python是什么意思中文-在python中%是什么意思" target="_blank">python是什么意思中文-在python中%是什么意思</a>
<span class="text-muted">编程大乐趣</span>
<div>Python中%有两种：1、数值运算：%代表取模，返回除法的余数。如：>>>7%212、%操作符（字符串格式化，stringformatting），说明如下：%[(name)][flags][width].[precision]typecode(name)为命名flags可以有+，-，''或0。+表示右对齐。-表示左对齐。''为一个空格，表示在正数的左侧填充一个空格，从而与负数对齐。0表示使用0填</div>
</li>
<li><a href="/article/1835497411179540480.htm"
title="深入理解 MultiQueryRetriever：提升向量数据库检索效果的强大工具" target="_blank">深入理解 MultiQueryRetriever：提升向量数据库检索效果的强大工具</a>
<span class="text-muted">nseejrukjhad</span>
<a class="tag" taget="_blank" href="/search/%E6%95%B0%E6%8D%AE%E5%BA%93/1.htm">数据库</a><a class="tag" taget="_blank" href="/search/python/1.htm">python</a>
<div>深入理解MultiQueryRetriever：提升向量数据库检索效果的强大工具引言在人工智能和自然语言处理领域，高效准确的信息检索一直是一个关键挑战。传统的基于距离的向量数据库检索方法虽然广泛应用，但仍存在一些局限性。本文将介绍一种创新的解决方案：MultiQueryRetriever，它通过自动生成多个查询视角来增强检索效果，提高结果的相关性和多样性。MultiQueryRetriever的工</div>
</li>
<li><a href="/article/1835495644123459584.htm"
title="Day1笔记-Python简介&标识符和关键字&输入输出" target="_blank">Day1笔记-Python简介&标识符和关键字&输入输出</a>
<span class="text-muted">~在杰难逃~</span>
<a class="tag" taget="_blank" href="/search/Python/1.htm">Python</a><a class="tag" taget="_blank" href="/search/python/1.htm">python</a><a class="tag" taget="_blank" href="/search/%E5%BC%80%E5%8F%91%E8%AF%AD%E8%A8%80/1.htm">开发语言</a><a class="tag" taget="_blank" href="/search/%E5%A4%A7%E6%95%B0%E6%8D%AE/1.htm">大数据</a><a class="tag" taget="_blank" href="/search/%E6%95%B0%E6%8D%AE%E5%88%86%E6%9E%90/1.htm">数据分析</a><a class="tag" taget="_blank" href="/search/%E6%95%B0%E6%8D%AE%E6%8C%96%E6%8E%98/1.htm">数据挖掘</a>
<div>大家好，从今天开始呢，杰哥开展一个新的专栏，当然，数据分析部分也会不定时更新的，这个新的专栏主要是讲解一些Python的基础语法和知识，帮助0基础的小伙伴入门和学习Python，感兴趣的小伙伴可以开始认真学习啦！一、Python简介【了解】1.计算机工作原理编程语言就是用来定义计算机程序的形式语言。我们通过编程语言来编写程序代码，再通过语言处理程序执行向计算机发送指令，让计算机完成对应的工作，编程</div>
</li>
<li><a href="/article/1835495517774245888.htm"
title="python八股文面试题分享及解析(1)" target="_blank">python八股文面试题分享及解析(1)</a>
<span class="text-muted">Shawn________</span>
<a class="tag" taget="_blank" href="/search/python/1.htm">python</a>
<div>#1.'''a=1b=2不用中间变量交换a和b'''#1.a=1b=2a,b=b,aprint(a)print(b)结果：21#2.ll=[]foriinrange(3):ll.append({'num':i})print(11)结果:#[{'num':0},{'num':1},{'num':2}]#3.kk=[]a={'num':0}foriinrange(3):#0,12#可变类型，不仅仅改变</div>
</li>
<li><a href="/article/1835493753557708800.htm"
title="每日算法&面试题，大厂特训二十八天——第二十天（树）" target="_blank">每日算法&面试题，大厂特训二十八天——第二十天（树）</a>
<span class="text-muted">肥学</span>
<a class="tag" taget="_blank" href="/search/%E2%9A%A1%E7%AE%97%E6%B3%95%E9%A2%98%E2%9A%A1%E9%9D%A2%E8%AF%95%E9%A2%98%E6%AF%8F%E6%97%A5%E7%B2%BE%E8%BF%9B/1.htm">⚡算法题⚡面试题每日精进</a><a class="tag" taget="_blank" href="/search/java/1.htm">java</a><a class="tag" taget="_blank" href="/search/%E7%AE%97%E6%B3%95/1.htm">算法</a><a class="tag" taget="_blank" href="/search/%E6%95%B0%E6%8D%AE%E7%BB%93%E6%9E%84/1.htm">数据结构</a>
<div>目录标题导读算法特训二十八天面试题点击直接资料领取导读肥友们为了更好的去帮助新同学适应算法和面试题，最近我们开始进行专项突击一步一步来。上一期我们完成了动态规划二十一天现在我们进行下一项对各类算法进行二十八天的一个小总结。还在等什么快来一起肥学进行二十八天挑战吧！！特别介绍小白练手专栏，适合刚入手的新人欢迎订阅编程小白进阶python有趣练手项目里面包括了像《机器人尬聊》《恶搞程序》这样的有趣文章</div>
</li>
<li><a href="/article/1835493626688401408.htm"
title="Python快速入门 —— 第三节：类与对象" target="_blank">Python快速入门 —— 第三节：类与对象</a>
<span class="text-muted">孤华暗香</span>
<a class="tag" taget="_blank" href="/search/Python%E5%BF%AB%E9%80%9F%E5%85%A5%E9%97%A8/1.htm">Python快速入门</a><a class="tag" taget="_blank" href="/search/python/1.htm">python</a><a class="tag" taget="_blank" href="/search/%E5%BC%80%E5%8F%91%E8%AF%AD%E8%A8%80/1.htm">开发语言</a>
<div>第三节：类与对象目标：了解面向对象编程的基础概念，并学会如何定义类和创建对象。内容：类与对象：定义类：class关键字。类的构造函数：__init__()。类的属性和方法。对象的创建与使用。示例：classStudent:def__init__(self,name,age,major):self.name&#</div>
</li>
<li><a href="/article/1835493374514262016.htm"
title="MongoDB Oplog 窗口" target="_blank">MongoDB Oplog 窗口</a>
<span class="text-muted">喝醉酒的小白</span>
<a class="tag" taget="_blank" href="/search/MongoDB/1.htm">MongoDB</a><a class="tag" taget="_blank" href="/search/%E8%BF%90%E7%BB%B4/1.htm">运维</a>
<div>在MongoDB中，oplog（操作日志）是一个特殊的日志系统，用于记录对数据库的所有写操作。oplog允许副本集成员（通常是从节点）应用主节点上已经执行的操作，从而保持数据的一致性。它是MongoDB副本集实现数据复制的基础。MongoDBOplog窗口oplog窗口是指在MongoDB副本集中，从节点可以用来同步数据的时间范围。这个窗口通常由以下因素决定：Oplog大小：oplog的大小是有限</div>
</li>
<li><a href="/article/1835492869062881280.htm"
title="pyecharts——绘制柱形图折线图" target="_blank">pyecharts——绘制柱形图折线图</a>
<span class="text-muted">2224070247</span>
<a class="tag" taget="_blank" href="/search/%E4%BF%A1%E6%81%AF%E5%8F%AF%E8%A7%86%E5%8C%96/1.htm">信息可视化</a><a class="tag" taget="_blank" href="/search/python/1.htm">python</a><a class="tag" taget="_blank" href="/search/java/1.htm">java</a><a class="tag" taget="_blank" href="/search/%E6%95%B0%E6%8D%AE%E5%8F%AF%E8%A7%86%E5%8C%96/1.htm">数据可视化</a>
<div>一、pyecharts概述自2013年6月百度EFE(ExcellentFrontEnd）数据可视化团队研发的ECharts1.0发布到GitHub网站以来，ECharts一直备受业界权威的关注并获得广泛好评，成为目前成熟且流行的数据可视化图表工具，被应用到诸多数据可视化的开发领域。Python作为数据分析领域最受欢迎的语言，也加入ECharts的使用行列，并研发出方便Python开发者使用的数据</div>
</li>
<li><a href="/article/1835491859351302144.htm"
title="Python 实现图片裁剪（附代码） | Python工具" target="_blank">Python 实现图片裁剪（附代码） | Python工具</a>
<span class="text-muted">剑客阿良_ALiang</span>
<div>前言本文提供将图片按照自定义尺寸进行裁剪的工具方法，一如既往的实用主义。环境依赖ffmpeg环境安装，可以参考我的另一篇文章：windowsffmpeg安装部署_阿良的博客-CSDN博客本文主要使用到的不是ffmpeg，而是ffprobe也在上面这篇文章中的zip包中。ffmpy安装：pipinstallffmpy-ihttps://pypi.douban.com/simple代码不废话了，上代码</div>
</li>
<li><a href="/article/1835491353451130880.htm"
title="【华为OD技术面试真题 - 技术面】- python八股文真题题库（4)" target="_blank">【华为OD技术面试真题 - 技术面】- python八股文真题题库（4)</a>
<span class="text-muted">算法大师</span>
<a class="tag" taget="_blank" href="/search/%E5%8D%8E%E4%B8%BAod/1.htm">华为od</a><a class="tag" taget="_blank" href="/search/%E9%9D%A2%E8%AF%95/1.htm">面试</a><a class="tag" taget="_blank" href="/search/python/1.htm">python</a>
<div>华为OD面试真题精选专栏：华为OD面试真题精选目录:2024华为OD面试手撕代码真题目录以及八股文真题目录文章目录华为OD面试真题精选**1.Python中的`with`**用途和功能自动资源管理示例：文件操作上下文管理协议示例代码工作流程解析优点2.\_\_new\_\_和**\_\_init\_\_**区别__new____init__区别总结3.**切片（Slicing）操作**基本切片语法</div>
</li>
<li><a href="/article/1835490974911000576.htm"
title="python os 环境变量" target="_blank">python os 环境变量</a>
<span class="text-muted">CV矿工</span>
<a class="tag" taget="_blank" href="/search/python/1.htm">python</a><a class="tag" taget="_blank" href="/search/%E5%BC%80%E5%8F%91%E8%AF%AD%E8%A8%80/1.htm">开发语言</a><a class="tag" taget="_blank" href="/search/numpy/1.htm">numpy</a>
<div>环境变量：环境变量是程序和操作系统之间的通信方式。有些字符不宜明文写进代码里，比如数据库密码，个人账户密码，如果写进自己本机的环境变量里，程序用的时候通过os.environ.get（）取出来就行了。os.environ是一个环境变量的字典。环境变量的相关操作importos"""设置/修改环境变量：os.environ[‘环境变量名称’]=‘环境变量值’#其中key和value均为string类</div>
</li>
<li><a href="/article/1835490218845761536.htm"
title="Python爬虫解析工具之xpath使用详解" target="_blank">Python爬虫解析工具之xpath使用详解</a>
<span class="text-muted">eqa11</span>
<a class="tag" taget="_blank" href="/search/python/1.htm">python</a><a class="tag" taget="_blank" href="/search/%E7%88%AC%E8%99%AB/1.htm">爬虫</a><a class="tag" taget="_blank" href="/search/%E5%BC%80%E5%8F%91%E8%AF%AD%E8%A8%80/1.htm">开发语言</a>
<div>文章目录Python爬虫解析工具之xpath使用详解一、引言二、环境准备1、插件安装2、依赖库安装三、xpath语法详解1、路径表达式2、通配符3、谓语4、常用函数四、xpath在Python代码中的使用1、文档树的创建2、使用xpath表达式3、获取元素内容和属性五、总结Python爬虫解析工具之xpath使用详解一、引言在Python爬虫开发中，数据提取是一个至关重要的环节。xpath作为一门</div>
</li>
<li><a href="/article/1835489460372992000.htm"
title="【PG】常见数据库、表属性设置" target="_blank">【PG】常见数据库、表属性设置</a>
<span class="text-muted">江无羡</span>
<a class="tag" taget="_blank" href="/search/%E6%95%B0%E6%8D%AE%E5%BA%93/1.htm">数据库</a>
<div>PG的常见属性配置方法数据库复制、备份相关表的复制标识单表操作批量表操作链接数据库复制、备份相关表的复制标识单表操作通过ALTER语句单独更改一张表的复制标识。ALTERTABLE[tablename]REPLICAIDENTITYFULL;批量表操作通过代码块的方式，对某个schema中的所有表一起更新其复制标识。SELECTtablename,CASErelreplidentWHEN'd'TH</div>
</li>
<li><a href="/article/1835483915071090688.htm"
title="【华为OD技术面试真题 - 技术面】- python八股文真题题库（1）" target="_blank">【华为OD技术面试真题 - 技术面】- python八股文真题题库（1）</a>
<span class="text-muted">算法大师</span>
<a class="tag" taget="_blank" href="/search/%E5%8D%8E%E4%B8%BAod/1.htm">华为od</a><a class="tag" taget="_blank" href="/search/%E9%9D%A2%E8%AF%95/1.htm">面试</a><a class="tag" taget="_blank" href="/search/python/1.htm">python</a>
<div>华为OD面试真题精选专栏：华为OD面试真题精选目录:2024华为OD面试手撕代码真题目录以及八股文真题目录文章目录华为OD面试真题精选1.数据预处理流程数据预处理的主要步骤工具和库2.介绍线性回归、逻辑回归模型线性回归（LinearRegression）模型形式：关键点：逻辑回归（LogisticRegression）模型形式：关键点：参数估计与评估：3.python浅拷贝及深拷贝浅拷贝（Shal</div>
</li>
<li><a href="/article/1835483159630802944.htm"
title="nosql数据库技术与应用知识点" target="_blank">nosql数据库技术与应用知识点</a>
<span class="text-muted">皆过客，揽星河</span>
<a class="tag" taget="_blank" href="/search/NoSQL/1.htm">NoSQL</a><a class="tag" taget="_blank" href="/search/nosql/1.htm">nosql</a><a class="tag" taget="_blank" href="/search/%E6%95%B0%E6%8D%AE%E5%BA%93/1.htm">数据库</a><a class="tag" taget="_blank" href="/search/%E5%A4%A7%E6%95%B0%E6%8D%AE/1.htm">大数据</a><a class="tag" taget="_blank" href="/search/%E6%95%B0%E6%8D%AE%E5%88%86%E6%9E%90/1.htm">数据分析</a><a class="tag" taget="_blank" href="/search/%E6%95%B0%E6%8D%AE%E7%BB%93%E6%9E%84/1.htm">数据结构</a><a class="tag" taget="_blank" href="/search/%E9%9D%9E%E5%85%B3%E7%B3%BB%E5%9E%8B%E6%95%B0%E6%8D%AE%E5%BA%93/1.htm">非关系型数据库</a>
<div>Nosql知识回顾大数据处理流程数据采集(flume、爬虫、传感器)数据存储(本门课程NoSQL所处的阶段)Hdfs、MongoDB、HBase等数据清洗(入仓)Hive等数据处理、分析(Spark、Flink等)数据可视化数据挖掘、机器学习应用(Python、SparkMLlib等)大数据时代存储的挑战(三高)高并发(同一时间很多人访问)高扩展(要求随时根据需求扩展存储)高效率(要求读写速度快)</div>
</li>
<li><a href="/article/1835481269690003456.htm"
title="《Python数据分析实战终极指南》" target="_blank">《Python数据分析实战终极指南》</a>
<span class="text-muted">xjt921122</span>
<a class="tag" taget="_blank" href="/search/python/1.htm">python</a><a class="tag" taget="_blank" href="/search/%E6%95%B0%E6%8D%AE%E5%88%86%E6%9E%90/1.htm">数据分析</a><a class="tag" taget="_blank" href="/search/%E5%BC%80%E5%8F%91%E8%AF%AD%E8%A8%80/1.htm">开发语言</a>
<div>对于分析师来说，大家在学习Python数据分析的路上，多多少少都遇到过很多大坑**，有关于技能和思维的**：Excel已经没办法处理现有的数据量了，应该学Python吗？找了一大堆Python和Pandas的资料来学习，为什么自己动手就懵了？跟着比赛类公开数据分析案例练了很久，为什么当自己面对数据需求还是只会数据处理而没有分析思路？学了对比、细分、聚类分析，也会用PEST、波特五力这类分析法，为啥</div>
</li>
<li><a href="/article/1835477614848995328.htm"
title="insert into select 主键自增_mybatis拦截器实现主键自动生成" target="_blank">insert into select 主键自增_mybatis拦截器实现主键自动生成</a>
<span class="text-muted">weixin_39521651</span>
<a class="tag" taget="_blank" href="/search/insert/1.htm">insert</a><a class="tag" taget="_blank" href="/search/into/1.htm">into</a><a class="tag" taget="_blank" href="/search/select/1.htm">select</a><a class="tag" taget="_blank" href="/search/%E4%B8%BB%E9%94%AE%E8%87%AA%E5%A2%9E/1.htm">主键自增</a><a class="tag" taget="_blank" href="/search/mybatis/1.htm">mybatis</a><a class="tag" taget="_blank" href="/search/delete%E8%BF%94%E5%9B%9E%E5%80%BC/1.htm">delete返回值</a><a class="tag" taget="_blank" href="/search/mybatis/1.htm">mybatis</a><a class="tag" taget="_blank" href="/search/insert%E8%BF%94%E5%9B%9E%E4%B8%BB%E9%94%AE/1.htm">insert返回主键</a><a class="tag" taget="_blank" href="/search/mybatis/1.htm">mybatis</a><a class="tag" taget="_blank" href="/search/insert%E8%BF%94%E5%9B%9E%E5%AF%B9%E8%B1%A1/1.htm">insert返回对象</a><a class="tag" taget="_blank" href="/search/mybatis/1.htm">mybatis</a><a class="tag" taget="_blank" href="/search/plus/1.htm">plus</a><a class="tag" taget="_blank" href="/search/insert%E8%BF%94%E5%9B%9E%E4%B8%BB%E9%94%AE/1.htm">insert返回主键</a><a class="tag" taget="_blank" href="/search/mybatis/1.htm">mybatis</a><a class="tag" taget="_blank" href="/search/plus/1.htm">plus</a><a class="tag" taget="_blank" href="/search/%E6%8F%92%E5%85%A5%E7%94%9F%E6%88%90id/1.htm">插入生成id</a>
<div>前言前阵子和朋友聊天，他说他们项目有个需求，要实现主键自动生成，不想每次新增的时候，都手动设置主键。于是我就问他，那你们数据库表设置主键自动递增不就得了。他的回答是他们项目目前的id都是采用雪花算法来生成，因此为了项目稳定性，不会切换id的生成方式。朋友问我有没有什么实现思路，他们公司的orm框架是mybatis，我就建议他说，不然让你老大把mybatis切换成mybatis-plus。mybat</div>
</li>
<li><a href="/article/1835477362700021760.htm"
title="Python中深拷贝与浅拷贝的区别" target="_blank">Python中深拷贝与浅拷贝的区别</a>
<span class="text-muted">yuxiaoyu.</span>
<div>转自：http://blog.csdn.net/u014745194/article/details/70271868定义：在Python中对象的赋值其实就是对象的引用。当创建一个对象，把它赋值给另一个变量的时候，python并没有拷贝这个对象，只是拷贝了这个对象的引用而已。浅拷贝：拷贝了最外围的对象本身，内部的元素都只是拷贝了一个引用而已。也就是，把对象复制一遍，但是该对象中引用的其他对象我不复</div>
</li>
<li><a href="/article/1835476983614631936.htm"
title="Python开发常用的三方模块如下：" target="_blank">Python开发常用的三方模块如下：</a>
<span class="text-muted">换个网名有点难</span>
<a class="tag" taget="_blank" href="/search/python/1.htm">python</a><a class="tag" taget="_blank" href="/search/%E5%BC%80%E5%8F%91%E8%AF%AD%E8%A8%80/1.htm">开发语言</a>
<div>Python是一门功能强大的编程语言，拥有丰富的第三方库，这些库为开发者提供了极大的便利。以下是100个常用的Python库，涵盖了多个领域：1、NumPy，用于科学计算的基础库。2、Pandas，提供数据结构和数据分析工具。3、Matplotlib，一个绘图库。4、Scikit-learn，机器学习库。5、SciPy，用于数学、科学和工程的库。6、TensorFlow，由Google开发的开源机</div>
</li>
<li><a href="/article/16.htm"
title="深入浅出Java Annotation(元注解和自定义注解）" target="_blank">深入浅出Java Annotation(元注解和自定义注解）</a>
<span class="text-muted">Josh_Persistence</span>
<a class="tag" taget="_blank" href="/search/Java+Annotation/1.htm">Java Annotation</a><a class="tag" taget="_blank" href="/search/%E5%85%83%E6%B3%A8%E8%A7%A3/1.htm">元注解</a><a class="tag" taget="_blank" href="/search/%E8%87%AA%E5%AE%9A%E4%B9%89%E6%B3%A8%E8%A7%A3/1.htm">自定义注解</a>
<div>一、基本概述
Annontation是Java5开始引入的新特征。中文名称一般叫注解。它提供了一种安全的类似注释的机制，用来将任何的信息或元数据（metadata）与程序元素（类、方法、成员变量等）进行关联。
更通俗的意思是为程序的元素（类、方法、成员变量）加上更直观更明了的说明，这些说明信息是与程序的业务逻辑无关，并且是供指定的工具或</div>
</li>
<li><a href="/article/143.htm"
title="mysql优化特定类型的查询" target="_blank">mysql优化特定类型的查询</a>
<span class="text-muted">annan211</span>
<a class="tag" taget="_blank" href="/search/java/1.htm">java</a><a class="tag" taget="_blank" href="/search/%E5%B7%A5%E4%BD%9C/1.htm">工作</a><a class="tag" taget="_blank" href="/search/mysql/1.htm">mysql</a>
<div>
本节所介绍的查询优化的技巧都是和特定版本相关的，所以对于未来mysql的版本未必适用。
1 优化count查询
对于count这个函数的网上的大部分资料都是错误的或者是理解的都是一知半解的。在做优化之前我们先来看看
真正的count()函数的作用到底是什么。
count()是一个特殊的函数，有两种非常不同的作用，他可以统计某个列值的数量，也可以统计行数。
在统</div>
</li>
<li><a href="/article/270.htm"
title="MAC下安装多版本JDK和切换几种方式" target="_blank">MAC下安装多版本JDK和切换几种方式</a>
<span class="text-muted">棋子chessman</span>
<a class="tag" taget="_blank" href="/search/jdk/1.htm">jdk</a>
<div>环境：
MAC AIR,OS X 10.10,64位
历史：
过去 Mac 上的 Java 都是由 Apple 自己提供，只支持到 Java 6，并且OS X 10.7 开始系统并不自带（而是可选安装）（原自带的是1.6）。
后来 Apple 加入 OpenJDK 继续支持 Java 6，而 Java 7 将由 Oracle 负责提供。
在终端中输入jav</div>
</li>
<li><a href="/article/397.htm"
title="javaScript （1）" target="_blank">javaScript （1）</a>
<span class="text-muted">Array_06</span>
<a class="tag" taget="_blank" href="/search/JavaScript/1.htm">JavaScript</a><a class="tag" taget="_blank" href="/search/java/1.htm">java</a><a class="tag" taget="_blank" href="/search/%E6%B5%8F%E8%A7%88%E5%99%A8/1.htm">浏览器</a>
<div>JavaScript
1、运算符
运算符就是完成操作的一系列符号，它有七类： 赋值运算符（=,+=,-=,*=,/=,%=,<<=,>>=,|=,&=）、算术运算符(+,-,*,/,++,--,%)、比较运算符(>,<,<=,>=,==,===,!=,!==)、逻辑运算符(||,&&,!)、条件运算(?:)、位</div>
</li>
<li><a href="/article/524.htm"
title="国内顶级代码分享网站" target="_blank">国内顶级代码分享网站</a>
<span class="text-muted">袁潇含</span>
<a class="tag" taget="_blank" href="/search/java/1.htm">java</a><a class="tag" taget="_blank" href="/search/jdk/1.htm">jdk</a><a class="tag" taget="_blank" href="/search/oracle/1.htm">oracle</a><a class="tag" taget="_blank" href="/search/.net/1.htm">.net</a><a class="tag" taget="_blank" href="/search/PHP/1.htm">PHP</a>
<div> 现在国内很多开源网站感觉都是为了利益而做的
当然利益是肯定的,否则谁也不会免费的去做网站
&</div>
</li>
<li><a href="/article/651.htm"
title="Elasticsearch、MongoDB和Hadoop比较" target="_blank">Elasticsearch、MongoDB和Hadoop比较</a>
<span class="text-muted">随意而生</span>
<a class="tag" taget="_blank" href="/search/mongodb/1.htm">mongodb</a><a class="tag" taget="_blank" href="/search/hadoop/1.htm">hadoop</a><a class="tag" taget="_blank" href="/search/%E6%90%9C%E7%B4%A2%E5%BC%95%E6%93%8E/1.htm">搜索引擎</a>
<div>
IT界在过去几年中出现了一个有趣的现象。很多新的技术出现并立即拥抱了“大数据”。稍微老一点的技术也会将大数据添进自己的特性，避免落大部队太远，我们看到了不同技术之间的边际的模糊化。假如你有诸如Elasticsearch或者Solr这样的搜索引擎，它们存储着JSON文档，MongoDB存着JSON文档，或者一堆JSON文档存放在一个Hadoop集群的HDFS中。你可以使用这三种配</div>
</li>
<li><a href="/article/778.htm"
title="mac os 系统科研软件总结" target="_blank">mac os 系统科研软件总结</a>
<span class="text-muted">张亚雄</span>
<a class="tag" taget="_blank" href="/search/mac+os/1.htm">mac os</a>
<div>1.1 Microsoft Office for Mac 2011
大客户版，自行搜索。
1.2 Latex （MacTex）:
系统环境：https://tug.org/mactex/
&nb</div>
</li>
<li><a href="/article/905.htm"
title="Maven实战（四）生命周期" target="_blank">Maven实战（四）生命周期</a>
<span class="text-muted">AdyZhang</span>
<a class="tag" taget="_blank" href="/search/maven/1.htm">maven</a>
<div>1. 三套生命周期 Maven拥有三套相互独立的生命周期，它们分别为clean，default和site。 每个生命周期包含一些阶段，这些阶段是有顺序的，并且后面的阶段依赖于前面的阶段，用户和Maven最直接的交互方式就是调用这些生命周期阶段。 以clean生命周期为例，它包含的阶段有pre-clean, clean 和 post</div>
</li>
<li><a href="/article/1032.htm"
title="Linux下Jenkins迁移" target="_blank">Linux下Jenkins迁移</a>
<span class="text-muted">aijuans</span>
<a class="tag" taget="_blank" href="/search/Jenkins/1.htm">Jenkins</a>
<div>1. 将Jenkins程序目录copy过去 源程序在/export/data/tomcatRoot/ofctest-jenkins.jd.com下面 tar -cvzf jenkins.tar.gz ofctest-jenkins.jd.com &</div>
</li>
<li><a href="/article/1159.htm"
title="request.getInputStream()只能获取一次的问题" target="_blank">request.getInputStream()只能获取一次的问题</a>
<span class="text-muted">ayaoxinchao</span>
<a class="tag" taget="_blank" href="/search/request/1.htm">request</a><a class="tag" taget="_blank" href="/search/Inputstream/1.htm">Inputstream</a>
<div>问题：在使用HTTP协议实现应用间接口通信时，服务端读取客户端请求过来的数据，会用到request.getInputStream()，第一次读取的时候可以读取到数据，但是接下来的读取操作都读取不到数据
原因： 1. 一个InputStream对象在被读取完成后，将无法被再次读取，始终返回-1； 2. InputStream并没有实现reset方法（可以重</div>
</li>
<li><a href="/article/1286.htm"
title="数据库SQL优化大总结之 百万级数据库优化方案" target="_blank">数据库SQL优化大总结之 百万级数据库优化方案</a>
<span class="text-muted">BigBird2012</span>
<a class="tag" taget="_blank" href="/search/SQL%E4%BC%98%E5%8C%96/1.htm">SQL优化</a>
<div>网上关于SQL优化的教程很多，但是比较杂乱。近日有空整理了一下，写出来跟大家分享一下，其中有错误和不足的地方，还请大家纠正补充。
这篇文章我花费了大量的时间查找资料、修改、排版，希望大家阅读之后，感觉好的话推荐给更多的人，让更多的人看到、纠正以及补充。
1.对查询进行优化，要尽量避免全表扫描，首先应考虑在 where 及 order by 涉及的列上建立索引。
2.应尽量避免在 where </div>
</li>
<li><a href="/article/1413.htm"
title="jsonObject的使用" target="_blank">jsonObject的使用</a>
<span class="text-muted">bijian1013</span>
<a class="tag" taget="_blank" href="/search/java/1.htm">java</a><a class="tag" taget="_blank" href="/search/json/1.htm">json</a>
<div> 在项目中难免会用java处理json格式的数据，因此封装了一个JSONUtil工具类。
JSONUtil.java
package com.bijian.json.study;
import java.util.ArrayList;
import java.util.Date;
import java.util.HashMap;</div>
</li>
<li><a href="/article/1540.htm"
title="[Zookeeper学习笔记之六]Zookeeper源代码分析之Zookeeper.WatchRegistration" target="_blank">[Zookeeper学习笔记之六]Zookeeper源代码分析之Zookeeper.WatchRegistration</a>
<span class="text-muted">bit1129</span>
<a class="tag" taget="_blank" href="/search/zookeeper/1.htm">zookeeper</a>
<div>Zookeeper类是Zookeeper提供给用户访问Zookeeper service的主要API，它包含了如下几个内部类
首先分析它的内部类，从WatchRegistration开始，为指定的znode path注册一个Watcher，
/**
* Register a watcher for a particular p</div>
</li>
<li><a href="/article/1667.htm"
title="【Scala十三】Scala核心七：部分应用函数" target="_blank">【Scala十三】Scala核心七：部分应用函数</a>
<span class="text-muted">bit1129</span>
<a class="tag" taget="_blank" href="/search/scala/1.htm">scala</a>
<div>何为部分应用函数？
Partially applied function: A function that’s used in an expression and that misses some of its arguments.For instance, if function f has type Int => Int => Int, then f and f(1) are p</div>
</li>
<li><a href="/article/1794.htm"
title="Tomcat Error listenerStart 终极大法" target="_blank">Tomcat Error listenerStart 终极大法</a>
<span class="text-muted">ronin47</span>
<a class="tag" taget="_blank" href="/search/tomcat/1.htm">tomcat</a>
<div>Tomcat报的错太含糊了，什么错都没报出来，只提示了Error listenerStart。为了调试，我们要获得更详细的日志。可以在WEB-INF/classes目录下新建一个文件叫logging.properties，内容如下
Java代码
handlers = org.apache.juli.FileHandler, java.util.logging.ConsoleHa</div>
</li>
<li><a href="/article/1921.htm"
title="不用加减符号实现加减法" target="_blank">不用加减符号实现加减法</a>
<span class="text-muted">BrokenDreams</span>
<a class="tag" taget="_blank" href="/search/%E5%AE%9E%E7%8E%B0/1.htm">实现</a>
<div> 今天有群友发了一个问题，要求不用加减符号(包括负号)来实现加减法。
分析一下，先看最简单的情况，假设1+1，按二进制算的话结果是10，可以看到从右往左的第一位变为0，第二位由于进位变为1。
</div>
</li>
<li><a href="/article/2048.htm"
title="读《研磨设计模式》-代码笔记-状态模式-State" target="_blank">读《研磨设计模式》-代码笔记-状态模式-State</a>
<span class="text-muted">bylijinnan</span>
<a class="tag" taget="_blank" href="/search/java/1.htm">java</a><a class="tag" taget="_blank" href="/search/%E8%AE%BE%E8%AE%A1%E6%A8%A1%E5%BC%8F/1.htm">设计模式</a>
<div>声明： 本文只为方便我个人查阅和理解，详细的分析以及源代码请移步 原作者的博客http://chjavach.iteye.com/
/*
当一个对象的内在状态改变时允许改变其行为，这个对象看起来像是改变了其类
状态模式主要解决的是当控制一个对象状态的条件表达式过于复杂时的情况
把状态的判断逻辑转移到表示不同状态的一系列类中，可以把复杂的判断逻辑简化
如果在</div>
</li>
<li><a href="/article/2175.htm"
title="CUDA程序block和thread超出硬件允许值时的异常" target="_blank">CUDA程序block和thread超出硬件允许值时的异常</a>
<span class="text-muted">cherishLC</span>
<a class="tag" taget="_blank" href="/search/CUDA/1.htm">CUDA</a>
<div>调用CUDA的核函数时指定block 和 thread大小，该大小可以是dim3类型的（三维数组），只用一维时可以是usigned int型的。
以下程序验证了当block或thread大小超出硬件允许值时会产生异常！！！GPU根本不会执行运算！！！
所以验证结果的正确性很重要！！！
在VS中创建CUDA项目会有一个模板，里面有更详细的状态验证。
以下程序在K5000GPU上跑的。</div>
</li>
<li><a href="/article/2302.htm"
title="诡异的超长时间GC问题定位" target="_blank">诡异的超长时间GC问题定位</a>
<span class="text-muted">chenchao051</span>
<a class="tag" taget="_blank" href="/search/jvm/1.htm">jvm</a><a class="tag" taget="_blank" href="/search/cms/1.htm">cms</a><a class="tag" taget="_blank" href="/search/GC/1.htm">GC</a><a class="tag" taget="_blank" href="/search/hbase/1.htm">hbase</a><a class="tag" taget="_blank" href="/search/swap/1.htm">swap</a>
<div>HBase的GC策略采用PawNew+CMS, 这是大众化的配置，ParNew经常会出现停顿时间特别长的情况，有时候甚至长到令人发指的地步，例如请看如下日志：
2012-10-17T05:54:54.293+0800: 739594.224: [GC 739606.508: [ParNew: 996800K->110720K(996800K), 178.8826900 secs] 3700</div>
</li>
<li><a href="/article/2429.htm"
title="maven环境快速搭建" target="_blank">maven环境快速搭建</a>
<span class="text-muted">daizj</span>
<a class="tag" taget="_blank" href="/search/%E5%AE%89%E8%A3%85/1.htm">安装</a><a class="tag" taget="_blank" href="/search/mavne/1.htm">mavne</a><a class="tag" taget="_blank" href="/search/%E7%8E%AF%E5%A2%83%E9%85%8D%E7%BD%AE/1.htm">环境配置</a>
<div>一 下载maven
安装maven之前，要先安装jdk及配置JAVA_HOME环境变量。这个安装和配置java环境不用多说。
maven下载地址：http://maven.apache.org/download.html，目前最新的是这个apache-maven-3.2.5-bin.zip，然后解压在任意位置，最好地址中不要带中文字符，这个做java 的都知道，地址中出现中文会出现很多</div>
</li>
<li><a href="/article/2556.htm"
title="PHP网站安全，避免PHP网站受到攻击的方法" target="_blank">PHP网站安全，避免PHP网站受到攻击的方法</a>
<span class="text-muted">dcj3sjt126com</span>
<a class="tag" taget="_blank" href="/search/PHP/1.htm">PHP</a>
<div>
对于PHP网站安全主要存在这样几种攻击方式:1、命令注入(Command Injection)2、eval注入(Eval Injection)3、客户端脚本攻击(Script Insertion)4、跨网站脚本攻击(Cross Site Scripting, XSS)5、SQL注入攻击(SQL injection)6、跨网站请求伪造攻击(Cross Site Request Forgerie</div>
</li>
<li><a href="/article/2683.htm"
title="yii中给CGridView设置默认的排序根据时间倒序的方法" target="_blank">yii中给CGridView设置默认的排序根据时间倒序的方法</a>
<span class="text-muted">dcj3sjt126com</span>
<a class="tag" taget="_blank" href="/search/GridView/1.htm">GridView</a>
<div>public function searchWithRelated() {
$criteria = new CDbCriteria;
$criteria->together = true; //without th</div>
</li>
<li><a href="/article/2810.htm"
title="Java集合对象和数组对象的转换" target="_blank">Java集合对象和数组对象的转换</a>
<span class="text-muted">dyy_gusi</span>
<a class="tag" taget="_blank" href="/search/java%E9%9B%86%E5%90%88/1.htm">java集合</a>
<div> 在开发中，我们经常需要将集合对象（List，Set）转换为数组对象，或者将数组对象转换为集合对象。Java提供了相互转换的工具，但是我们使用的时候需要注意，不能乱用滥用。
1、数组对象转换为集合对象
最暴力的方式是new一个集合对象，然后遍历数组，依次将数组中的元素放入到新的集合中，但是这样做显然过</div>
</li>
<li><a href="/article/2937.htm"
title="nginx同一主机部署多个应用" target="_blank">nginx同一主机部署多个应用</a>
<span class="text-muted">geeksun</span>
<a class="tag" taget="_blank" href="/search/nginx/1.htm">nginx</a>
<div>近日有一需求，需要在一台主机上用nginx部署2个php应用，分别是wordpress和wiki，探索了半天，终于部署好了，下面把过程记录下来。
1. 在nginx下创建vhosts目录，用以放置vhost文件。
mkdir vhosts
2. 修改nginx.conf的配置， 在http节点增加下面内容设置，用来包含vhosts里的配置文件
#</div>
</li>
<li><a href="/article/3064.htm"
title="ubuntu添加admin权限的用户账号" target="_blank">ubuntu添加admin权限的用户账号</a>
<span class="text-muted">hongtoushizi</span>
<a class="tag" taget="_blank" href="/search/ubuntu/1.htm">ubuntu</a><a class="tag" taget="_blank" href="/search/useradd/1.htm">useradd</a>
<div>ubuntu创建账号的方式通常用到两种：useradd 和adduser . 本人尝试了useradd方法，步骤如下：
1:useradd
使用useradd时，如果后面不加任何参数的话，如：sudo useradd sysadm 创建出来的用户将是默认的三无用户：无home directory ,无密码,无系统shell。
顾应该如下操作：
</div>
</li>
<li><a href="/article/3191.htm"
title="第五章 常用Lua开发库2-JSON库、编码转换、字符串处理" target="_blank">第五章 常用Lua开发库2-JSON库、编码转换、字符串处理</a>
<span class="text-muted">jinnianshilongnian</span>
<a class="tag" taget="_blank" href="/search/nginx/1.htm">nginx</a><a class="tag" taget="_blank" href="/search/lua/1.htm">lua</a>
<div> JSON库
在进行数据传输时JSON格式目前应用广泛，因此从Lua对象与JSON字符串之间相互转换是一个非常常见的功能；目前Lua也有几个JSON库，本人用过cjson、dkjson。其中cjson的语法严格（比如unicode \u0020\u7eaf），要求符合规范否则会解析失败（如\u002），而dkjson相对宽松，当然也可以通过修改cjson的源码来完成</div>
</li>
<li><a href="/article/3318.htm"
title="Spring定时器配置的两种实现方式OpenSymphony Quartz和java Timer详解" target="_blank">Spring定时器配置的两种实现方式OpenSymphony Quartz和java Timer详解</a>
<span class="text-muted">yaerfeng1989</span>
<a class="tag" taget="_blank" href="/search/timer/1.htm">timer</a><a class="tag" taget="_blank" href="/search/quartz/1.htm">quartz</a><a class="tag" taget="_blank" href="/search/%E5%AE%9A%E6%97%B6%E5%99%A8/1.htm">定时器</a>
<div>原创整理不易，转载请注明出处：Spring定时器配置的两种实现方式OpenSymphony Quartz和java Timer详解
代码下载地址：http://www.zuidaima.com/share/1772648445103104.htm
有两种流行Spring定时器配置：Java的Timer类和OpenSymphony的Quartz。
1.Java Timer定时
首先继承jav</div>
</li>
<li><a href="/article/3445.htm"
title="Linux下df与du两个命令的差别？" target="_blank">Linux下df与du两个命令的差别？</a>
<span class="text-muted">pda158</span>
<a class="tag" taget="_blank" href="/search/linux/1.htm">linux</a>
<div> 一、df显示文件系统的使用情况，与du比較，就是更全盘化。 最经常使用的就是 df -T，显示文件系统的使用情况并显示文件系统的类型。 举比例如以下： [root@localhost ~]# df -T Filesystem Type &n</div>
</li>
<li><a href="/article/3572.htm"
title="[转]SQLite的工具类 ---- 通过反射把Cursor封装到VO对象" target="_blank">[转]SQLite的工具类 ---- 通过反射把Cursor封装到VO对象</a>
<span class="text-muted">ctfzh</span>
<a class="tag" taget="_blank" href="/search/VO/1.htm">VO</a><a class="tag" taget="_blank" href="/search/android/1.htm">android</a><a class="tag" taget="_blank" href="/search/sqlite/1.htm">sqlite</a><a class="tag" taget="_blank" href="/search/%E5%8F%8D%E5%B0%84/1.htm">反射</a><a class="tag" taget="_blank" href="/search/Cursor/1.htm">Cursor</a>
<div>在写DAO层时，觉得从Cursor里一个一个的取出字段值再装到VO(值对象)里太麻烦了，就写了一个工具类，用到了反射，可以把查询记录的值装到对应的VO里，也可以生成该VO的List。
使用时需要注意：
考虑到Android的性能问题，VO没有使用Setter和Getter，而是直接用public的属性。
表中的字段名需要和VO的属性名一样，要是不一样就得在查询的SQL中</div>
</li>
<li><a href="/article/3699.htm"
title="该学习笔记用到的Employee表" target="_blank">该学习笔记用到的Employee表</a>
<span class="text-muted">vipbooks</span>
<a class="tag" taget="_blank" href="/search/oracle/1.htm">oracle</a><a class="tag" taget="_blank" href="/search/sql/1.htm">sql</a><a class="tag" taget="_blank" href="/search/%E5%B7%A5%E4%BD%9C/1.htm">工作</a>
<div> 这是我在学习Oracle是用到的Employee表，在该笔记中用到的就是这张表，大家可以用它来学习和练习。
drop table Employee;
-- 员工信息表
create table Employee(
-- 员工编号
EmpNo number(3) primary key,
-- 姓</div>
</li>
</ul>
</div>
</div>
</div>
<div>
<div class="container">
<div class="indexes">
<strong>按字母分类：</strong>
<a href="/tags/A/1.htm" target="_blank">A</a><a href="/tags/B/1.htm" target="_blank">B</a><a href="/tags/C/1.htm" target="_blank">C</a><a
href="/tags/D/1.htm" target="_blank">D</a><a href="/tags/E/1.htm" target="_blank">E</a><a href="/tags/F/1.htm" target="_blank">F</a><a
href="/tags/G/1.htm" target="_blank">G</a><a href="/tags/H/1.htm" target="_blank">H</a><a href="/tags/I/1.htm" target="_blank">I</a><a
href="/tags/J/1.htm" target="_blank">J</a><a href="/tags/K/1.htm" target="_blank">K</a><a href="/tags/L/1.htm" target="_blank">L</a><a
href="/tags/M/1.htm" target="_blank">M</a><a href="/tags/N/1.htm" target="_blank">N</a><a href="/tags/O/1.htm" target="_blank">O</a><a
href="/tags/P/1.htm" target="_blank">P</a><a href="/tags/Q/1.htm" target="_blank">Q</a><a href="/tags/R/1.htm" target="_blank">R</a><a
href="/tags/S/1.htm" target="_blank">S</a><a href="/tags/T/1.htm" target="_blank">T</a><a href="/tags/U/1.htm" target="_blank">U</a><a
href="/tags/V/1.htm" target="_blank">V</a><a href="/tags/W/1.htm" target="_blank">W</a><a href="/tags/X/1.htm" target="_blank">X</a><a
href="/tags/Y/1.htm" target="_blank">Y</a><a href="/tags/Z/1.htm" target="_blank">Z</a><a href="/tags/0/1.htm" target="_blank">其他</a>
</div>
</div>
</div>
<footer id="footer" class="mb30 mt30">
<div class="container">
<div class="footBglm">
<a target="_blank" href="/">首页</a> -
<a target="_blank" href="/custom/about.htm">关于我们</a> -
<a target="_blank" href="/search/Java/1.htm">站内搜索</a> -
<a target="_blank" href="/sitemap.txt">Sitemap</a> -
<a target="_blank" href="/custom/delete.htm">侵权投诉</a>
</div>
<div class="copyright">版权所有 IT知识库 CopyRight © 2000-2050 E-COM-NET.COM , All Rights Reserved.
<!-- <a href="https://beian.miit.gov.cn/" rel="nofollow" target="_blank">京ICP备09083238号</a><br>-->
</div>
</div>
</footer>
<!-- 代码高亮 -->
<script type="text/javascript" src="/static/syntaxhighlighter/scripts/shCore.js"></script>
<script type="text/javascript" src="/static/syntaxhighlighter/scripts/shLegacy.js"></script>
<script type="text/javascript" src="/static/syntaxhighlighter/scripts/shAutoloader.js"></script>
<link type="text/css" rel="stylesheet" href="/static/syntaxhighlighter/styles/shCoreDefault.css"/>
<script type="text/javascript" src="/static/syntaxhighlighter/src/my_start_1.js"></script>
</body>
</html>