大数据正式11 小咪咪 2022-06-05 07:12 162阅读 0赞 # 大数据正式11 # ### 数据库概述 ### * 是什么 # # 存储数据的仓库，其本质是文件系统，数据按照指定的格式将数据存储起来，用户可以对是数据库中的数据进行增删改查 * 数据库管理系统 # # DBMS，指一种操作和管理数据库的大型软件，用于建立、使用和维护数据库，对数据库进行统一管理和控制，以保证数据库的安全性和完善性。用户通过数据库管理系统访问数据表内的数据。 * 常见的数据库管理系统 # # 1. MySQL：开源；免费；小型； 2. Oracle：收费；大型； 3. DB2：收费 4. SQLServer：收费 5. SyBase： 6. SQLite：嵌入式小型数据库，应用在手机端 ### MySql ### * 客户端->DBMS->数据库->表 * 数据库表 * 数据库中的以表为组织单位存储数据 * 表似我们的java类，每个字段都有数据类型 # # 类---表 属性---字段 对象---记录 * 表数据 * 一行数据--------记录 * 安装MySQL * 开启MySQL服务 * net start mysql * 登录数据库 * mysql -u用户名 -p密码 * Mysql的图形化开发工具 * SQLyog * 数据库语言 * SQL：Structured Query Language * SQL分类： * 数据库定义语言：DDL（Data Definition Language）：用来定义数据库对象【数据库、表、列】，关键词【create，alter，drop】 * 数据库操作语言：DML（Data Manipulation Language）：用来对数据库表的记录进行更新，关键字【insert，delete，update】 * 数据库控制语言：DCL（Data Control Language）：用来定义数据库的访问权限和安全级别，及创建用户 * 数据库查询语言：用来查询数据库中表达的记录，关键字【select，from，where等】 * 通用语法 * SQL单行，双行，以分号结尾 * 可使用空格和缩进来增强语句的可读性 * mysql不区分大小写， 建议使用大写 * 同样可以使用/\*\*/的方式完成注释 * mysql中常使用的数据类型 * int * double * varchar * date <table style="margin-top:15px; margin-right:0px; margin-bottom:15px; margin-left:0px; padding-top:0px; padding-right:0px; padding-bottom:0px; padding-left:0px; border-top-width:0px; border-right-width:0px; border-bottom-width:0px; border-left-width:0px; border-style:initial; border-color:initial"> <thead style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:0px; padding-right:0px; padding-bottom:0px; padding-left:0px; border-top-width:0px; border-right-width:0px; border-bottom-width:0px; border-left-width:0px; border-style:initial; border-color:initial"> <tr style="margin:0px; padding:0px; border-width:1px 0px 0px; border-right-style:initial; border-bottom-style:initial; border-left-style:initial; border-right-color:initial; border-bottom-color:initial; border-left-color:initial; border-top-style:solid; border-top-color:rgb(204,204,204)"> <th style="margin:0px; padding:6px 13px; border-width:1px; border-style:solid; border-color:rgb(204,204,204)"> 分类</th> <th style="margin:0px; padding:6px 13px; border-width:1px; border-style:solid; border-color:rgb(204,204,204)"> 类型名称</th> <th style="margin:0px; padding:6px 13px; border-width:1px; border-style:solid; border-color:rgb(204,204,204)"> 说明</th> </tr> </thead> <tbody style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:0px; padding-right:0px; padding-bottom:0px; padding-left:0px; border-top-width:0px; border-right-width:0px; border-bottom-width:0px; border-left-width:0px; border-style:initial; border-color:initial"> <tr style="margin:0px; padding:0px; border-width:1px 0px 0px; border-right-style:initial; border-bottom-style:initial; border-left-style:initial; border-right-color:initial; border-bottom-color:initial; border-left-color:initial; border-top-style:solid; border-top-color:rgb(204,204,204)"> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> 整数类型</td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> tinyInt</td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> 很小的整数</td> </tr> <tr style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:0px; padding-right:0px; padding-bottom:0px; padding-left:0px; border-top-width:1px; border-right-width:0px; border-bottom-width:0px; border-left-width:0px; border-style:initial; border-color:initial; border-top-style:solid; border-top-color:rgb(204,204,204); background-color:rgb(248,248,248)"> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> </td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> smallInt</td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> 小的整数</td> </tr> <tr style="margin:0px; padding:0px; border-width:1px 0px 0px; border-right-style:initial; border-bottom-style:initial; border-left-style:initial; border-right-color:initial; border-bottom-color:initial; border-left-color:initial; border-top-style:solid; border-top-color:rgb(204,204,204)"> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> </td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> mediumint</td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> 中等大小的整数</td> </tr> <tr style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:0px; padding-right:0px; padding-bottom:0px; padding-left:0px; border-top-width:1px; border-right-width:0px; border-bottom-width:0px; border-left-width:0px; border-style:initial; border-color:initial; border-top-style:solid; border-top-color:rgb(204,204,204); background-color:rgb(248,248,248)"> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> int（integer）</td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> 普通大小的整数</td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> </td> </tr> <tr style="margin:0px; padding:0px; border-width:1px 0px 0px; border-right-style:initial; border-bottom-style:initial; border-left-style:initial; border-right-color:initial; border-bottom-color:initial; border-left-color:initial; border-top-style:solid; border-top-color:rgb(204,204,204)"> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> 小数类型</td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> float</td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> 单精度浮点数</td> </tr> <tr style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:0px; padding-right:0px; padding-bottom:0px; padding-left:0px; border-top-width:1px; border-right-width:0px; border-bottom-width:0px; border-left-width:0px; border-style:initial; border-color:initial; border-top-style:solid; border-top-color:rgb(204,204,204); background-color:rgb(248,248,248)"> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> </td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> double</td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> 双精度浮点数</td> </tr> <tr style="margin:0px; padding:0px; border-width:1px 0px 0px; border-right-style:initial; border-bottom-style:initial; border-left-style:initial; border-right-color:initial; border-bottom-color:initial; border-left-color:initial; border-top-style:solid; border-top-color:rgb(204,204,204)"> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> </td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> decimal（m,d）</td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> 压缩严格的指定数</td> </tr> <tr style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:0px; padding-right:0px; padding-bottom:0px; padding-left:0px; border-top-width:1px; border-right-width:0px; border-bottom-width:0px; border-left-width:0px; border-style:initial; border-color:initial; border-top-style:solid; border-top-color:rgb(204,204,204); background-color:rgb(248,248,248)"> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> 日期类型</td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> year</td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> YYYY 1901~2155</td> </tr> <tr style="margin:0px; padding:0px; border-width:1px 0px 0px; border-right-style:initial; border-bottom-style:initial; border-left-style:initial; border-right-color:initial; border-bottom-color:initial; border-left-color:initial; border-top-style:solid; border-top-color:rgb(204,204,204)"> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> </td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> time</td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> HH:MM:SS -838:59:59~838:59:59</td> </tr> <tr style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:0px; padding-right:0px; padding-bottom:0px; padding-left:0px; border-top-width:1px; border-right-width:0px; border-bottom-width:0px; border-left-width:0px; border-style:initial; border-color:initial; border-top-style:solid; border-top-color:rgb(204,204,204); background-color:rgb(248,248,248)"> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> </td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> data</td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> YYYY-MM-DD 1000-01-01~9999-12-31</td> </tr> <tr style="margin:0px; padding:0px; border-width:1px 0px 0px; border-right-style:initial; border-bottom-style:initial; border-left-style:initial; border-right-color:initial; border-bottom-color:initial; border-left-color:initial; border-top-style:solid; border-top-color:rgb(204,204,204)"> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> </td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> datatime</td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> YYYY-MM-DD HH:MM:SS 1000-01-01 00:00:00~9999-12-31 23:59:59</td> </tr> <tr style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:0px; padding-right:0px; padding-bottom:0px; padding-left:0px; border-top-width:1px; border-right-width:0px; border-bottom-width:0px; border-left-width:0px; border-style:initial; border-color:initial; border-top-style:solid; border-top-color:rgb(204,204,204); background-color:rgb(248,248,248)"> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> </td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> timestamp</td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> YYYY-MM-DD HH:MM:SS 1970-01-01 00:00:01~2038-01-19 03:14:07UTC</td> </tr> <tr style="margin:0px; padding:0px; border-width:1px 0px 0px; border-right-style:initial; border-bottom-style:initial; border-left-style:initial; border-right-color:initial; border-bottom-color:initial; border-left-color:initial; border-top-style:solid; border-top-color:rgb(204,204,204)"> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> 二进制文件</td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> CHAR（M）</td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> 0~255之间的整数</td> </tr> <tr style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:0px; padding-right:0px; padding-bottom:0px; padding-left:0px; border-top-width:1px; border-right-width:0px; border-bottom-width:0px; border-left-width:0px; border-style:initial; border-color:initial; border-top-style:solid; border-top-color:rgb(204,204,204); background-color:rgb(248,248,248)"> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> </td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> VARCHAR（M）</td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> 0~65535之间的整数</td> </tr> <tr style="margin:0px; padding:0px; border-width:1px 0px 0px; border-right-style:initial; border-bottom-style:initial; border-left-style:initial; border-right-color:initial; border-bottom-color:initial; border-left-color:initial; border-top-style:solid; border-top-color:rgb(204,204,204)"> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> </td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> TINYBLOB</td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> 0~255字节</td> </tr> <tr style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:0px; padding-right:0px; padding-bottom:0px; padding-left:0px; border-top-width:1px; border-right-width:0px; border-bottom-width:0px; border-left-width:0px; border-style:initial; border-color:initial; border-top-style:solid; border-top-color:rgb(204,204,204); background-color:rgb(248,248,248)"> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> </td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> BLOB</td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> 允许长度为0~65535字节</td> </tr> <tr style="margin:0px; padding:0px; border-width:1px 0px 0px; border-right-style:initial; border-bottom-style:initial; border-left-style:initial; border-right-color:initial; border-bottom-color:initial; border-left-color:initial; border-top-style:solid; border-top-color:rgb(204,204,204)"> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> </td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> MEDIUMBLOB</td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> 0~167772150字节</td> </tr> <tr style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:0px; padding-right:0px; padding-bottom:0px; padding-left:0px; border-top-width:1px; border-right-width:0px; border-bottom-width:0px; border-left-width:0px; border-style:initial; border-color:initial; border-top-style:solid; border-top-color:rgb(204,204,204); background-color:rgb(248,248,248)"> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> </td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> LONGBLOB</td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> 0~4294967395字节</td> </tr> <tr style="margin:0px; padding:0px; border-width:1px 0px 0px; border-right-style:initial; border-bottom-style:initial; border-left-style:initial; border-right-color:initial; border-bottom-color:initial; border-left-color:initial; border-top-style:solid; border-top-color:rgb(204,204,204)"> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> </td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> TINYTEXT</td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> 0~255字节</td> </tr> <tr style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:0px; padding-right:0px; padding-bottom:0px; padding-left:0px; border-top-width:1px; border-right-width:0px; border-bottom-width:0px; border-left-width:0px; border-style:initial; border-color:initial; border-top-style:solid; border-top-color:rgb(204,204,204); background-color:rgb(248,248,248)"> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> </td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> TEXT</td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> 0~65535字节</td> </tr> <tr style="margin:0px; padding:0px; border-width:1px 0px 0px; border-right-style:initial; border-bottom-style:initial; border-left-style:initial; border-right-color:initial; border-bottom-color:initial; border-left-color:initial; border-top-style:solid; border-top-color:rgb(204,204,204)"> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> </td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> MEDIUMTEXT</td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> 0~167772150字节</td> </tr> <tr style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:0px; padding-right:0px; padding-bottom:0px; padding-left:0px; border-top-width:1px; border-right-width:0px; border-bottom-width:0px; border-left-width:0px; border-style:initial; border-color:initial; border-top-style:solid; border-top-color:rgb(204,204,204); background-color:rgb(248,248,248)"> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> </td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> LONGTEXT</td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> 0~4294967395</td> </tr> <tr style="margin:0px; padding:0px; border-width:1px 0px 0px; border-right-style:initial; border-bottom-style:initial; border-left-style:initial; border-right-color:initial; border-bottom-color:initial; border-left-color:initial; border-top-style:solid; border-top-color:rgb(204,204,204)"> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> </td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> VARBINARY（M）</td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> 0~M个字节变长字符串</td> </tr> <tr style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:0px; padding-right:0px; padding-bottom:0px; padding-left:0px; border-top-width:1px; border-right-width:0px; border-bottom-width:0px; border-left-width:0px; border-style:initial; border-color:initial; border-top-style:solid; border-top-color:rgb(204,204,204); background-color:rgb(248,248,248)"> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> </td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> BINARY（M）</td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> 0~M个字节的定长字符串</td> </tr> </tbody> </table> ### 数据库操作 ### * database * 创建数据库 * create database 数据库名； * create database 数据库名 character set 字符集； * 查看数据库 * show databases;/查看所有的数据库名/ * show create database 数据库名；/查看数据库定义的信息/ * 删除数据库 * drop database 数据库名； * 切换数据库 * use 数据库名； * 查看正在使用的数据 * select database() ; * table * 创建表 * create table 表名（字段名1 类型（长度） 约束字段，字段名2 类型（长度） 约束）； * 主键约束 * 用于标识的当前记录的字段，特点非空，唯一。 * primary key * primary key(字段名) * 删除主键 * alter table 表名 drop primary key; * 主键自动增长 * primary key auto\_increment * 查看表 * show tables； * 查看表结构desc 表名； * 删除表 * drop table 表名； * 修改表结构格式 * 添加列 * alter table 表名 add 列名 类型（长度） 约束； * 修改列的类型和长度 * alter table 表名 modify 列名 类型（长度） 约束； * 修改列名 * alter table 表名 change 旧列名 新列名 类型（长度） 约束； * 删除列 * alter table 表名 drop 列名； * 修改表名 * rename table 表名 to 新表名； * 修改表的字符集 * alter table 表名 character set 字符集； * 插入表记录 * insert into 表名（列1，列2...） values(值1，值2...);/插入某些列/ * insert into 表名 values（值1，值2...）；/插入全部列/ * 自动增长的数据插入null即可 * 更新表记录 * update 表名 set 字段名 = 值，字段名=值； * update 表名 set 字段名 = 值， 字段名=值 where 条件； * 注：字符串和日期需要加'' * 删除记录 * delete from 表名 where 条件；/一条一条删除，不清空auto\_increment记录数/ * truncate table 表名；/删除整个表，重建新表，auto\_increment将被清空/ * DOS操作数据乱码 * 原因：mysql客户端与dos的编码不一致 * 查看所有mysql的编码 * show variables like 'character%';d * 与客户端有关的编码设置 * client connection result和客户端相关 * database server system 和服务器端相关 * 修改 * 客户端（只针对当前窗口） * set character\_set\_results =gbk; * 配置文件 * mysql安装目录下，my.ini文件 * default-character-set=gbk/客户端编码设置/ * character-set-server=utf-8/服务器端编码设置/ * sql查询语句 * 查询指定字段的信息 * select 字段1，字段2 from 表名； * 查询表中所有字段 * select \* from 表名； * 去除重复记录 * select distinct 字段 from 表名； * 别名查询 * select \* from 表名 as 别名； * select \* from 表名 别名； * select 字段 as 别名 from 表名； * select 字段 别名 from 表名； * 运算（列可直接进行运算） * select namne，price+122 from 表名； * 条件查询 * select 字段 from 表名 where 条件； <table style="margin-top:15px; margin-right:0px; margin-bottom:15px; margin-left:0px; padding-top:0px; padding-right:0px; padding-bottom:0px; padding-left:0px; border-top-width:0px; border-right-width:0px; border-bottom-width:0px; border-left-width:0px; border-style:initial; border-color:initial"> <thead style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:0px; padding-right:0px; padding-bottom:0px; padding-left:0px; border-top-width:0px; border-right-width:0px; border-bottom-width:0px; border-left-width:0px; border-style:initial; border-color:initial"> <tr style="margin:0px; padding:0px; border-width:1px 0px 0px; border-right-style:initial; border-bottom-style:initial; border-left-style:initial; border-right-color:initial; border-bottom-color:initial; border-left-color:initial; border-top-style:solid; border-top-color:rgb(204,204,204)"> <th style="margin:0px; padding:6px 13px; border-width:1px; border-style:solid; border-color:rgb(204,204,204)"> 比较运算符</th> <th style="margin:0px; padding:6px 13px; border-width:1px; border-style:solid; border-color:rgb(204,204,204)"> >< <=>= = <></th> <th style="margin:0px; padding:6px 13px; border-width:1px; border-style:solid; border-color:rgb(204,204,204)"> 大于 小于 小于等于 大于等于 等于 不等于</th> </tr> </thead> <tbody style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:0px; padding-right:0px; padding-bottom:0px; padding-left:0px; border-top-width:0px; border-right-width:0px; border-bottom-width:0px; border-left-width:0px; border-style:initial; border-color:initial"> <tr style="margin:0px; padding:0px; border-width:1px 0px 0px; border-right-style:initial; border-bottom-style:initial; border-left-style:initial; border-right-color:initial; border-bottom-color:initial; border-left-color:initial; border-top-style:solid; border-top-color:rgb(204,204,204)"> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> </td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> between ...and...</td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> 显示某一区间的值（含头含尾）</td> </tr> <tr style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:0px; padding-right:0px; padding-bottom:0px; padding-left:0px; border-top-width:1px; border-right-width:0px; border-bottom-width:0px; border-left-width:0px; border-style:initial; border-color:initial; border-top-style:solid; border-top-color:rgb(204,204,204); background-color:rgb(248,248,248)"> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> </td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> int（值，值）</td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> 显示在in列表的值</td> </tr> <tr style="margin:0px; padding:0px; border-width:1px 0px 0px; border-right-style:initial; border-bottom-style:initial; border-left-style:initial; border-right-color:initial; border-bottom-color:initial; border-left-color:initial; border-top-style:solid; border-top-color:rgb(204,204,204)"> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> </td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> like 通配符</td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> 模糊查询，like 有两个通配符 %匹配多个字符 _匹配一个字符</td> </tr> <tr style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:0px; padding-right:0px; padding-bottom:0px; padding-left:0px; border-top-width:1px; border-right-width:0px; border-bottom-width:0px; border-left-width:0px; border-style:initial; border-color:initial; border-top-style:solid; border-top-color:rgb(204,204,204); background-color:rgb(248,248,248)"> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> </td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> is null</td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> 判断是否为空</td> </tr> <tr style="margin:0px; padding:0px; border-width:1px 0px 0px; border-right-style:initial; border-bottom-style:initial; border-left-style:initial; border-right-color:initial; border-bottom-color:initial; border-left-color:initial; border-top-style:solid; border-top-color:rgb(204,204,204)"> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> 逻辑运算符</td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> and</td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> 多个条件同时成立</td> </tr> <tr style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:0px; padding-right:0px; padding-bottom:0px; padding-left:0px; border-top-width:1px; border-right-width:0px; border-bottom-width:0px; border-left-width:0px; border-style:initial; border-color:initial; border-top-style:solid; border-top-color:rgb(204,204,204); background-color:rgb(248,248,248)"> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> </td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> or</td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> 多个条件任意一个成立</td> </tr> <tr style="margin:0px; padding:0px; border-width:1px 0px 0px; border-right-style:initial; border-bottom-style:initial; border-left-style:initial; border-right-color:initial; border-bottom-color:initial; border-left-color:initial; border-top-style:solid; border-top-color:rgb(204,204,204)"> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> </td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> not</td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> 不成立 eg：where（age>100）</td> </tr> </tbody> </table> * 排序 * 查询语句 order by 字段名 asc；/升序/ * 查询语句 order by 字段名 desc； /降序/ * 聚合函数查询 * count 统计指定列不为null的记录行数 * sum计算指定列的数值和，如果指定的列不是数值，返回0 * max最大值--如果是字符串的话，用字符串的排序算法 * min最大值--如果是字符串的话，用字符串的排序 * avg平均值--不是数值类型返回0； * 分组 * 查询语句 group by 字段 having 条件； //having对数据进行过滤的 # # where和having的区别 1. having是在分组后进行数据过滤；where在分组前进行过滤 2. having后面可以使用分组函数（统计函数）；where后面不可以使用分组函数。 select parent,sum(money) from zhangwu group by parent having sum(money)>100; # JDBC # ### JDBC概述 ### * java database connectivity * 用于执行sql的javaAPI * 它由一组用java语言编写的类和接口组成 * JDBC是接口，驱动是接口的实现 ### JDBC原理 ### * 开发步骤 # # 导入驱动jar包--创建lib目录，用于存放当前项目所所需要的jar包 1. 注册驱动 1. Class.forName("com.mysql.jdbc.Driver"); 2. DriverManager.registerDriver(new com.mysql.jdbc.Driver());//不建议使用--两次注册 2. 获得连接 1. Connection conn=DriverManager.getConnection("jdbc:mysql://localhost:3306/数据库名","账号","密码"); 3. 获得语句执行平台 1. Statement stat = conn.createStatement(); 4. 执行sql语句 1. executeUpdate（String sql） 2. executeQuery(String sql) 3. execute(String sql) 5. 处理结果 1. ResultSet 2. 实际上就是一张二维表格 3. next()指向某行记录 4. getXXX(String name) 5. getXXX(int col) 6. 释放资源 1. rs.close(); 2. stmt.close(); 3. con.close(); ### sql注入 ### * 输入账号密码时，如果写成这样： # # select * from 用户表 where name = 用户输入的用户名 and password = 用户输入的密码； * sql注入 # # 密码为 XXX' or '1'='a * 组合起来就是 # # select * from 用户表 where name = 用户名 and password ='XXX' or 'a'='a'; * 上述语句可以查询出结果，即直接登录成功 ### 解决sql注入问题-PreparedStatement ### * 方法 * executeUpdate（）--执行insert，update，delete * executeQuery（）--执行select * execute（）执行select返回true，其他返回false * 设置实际参数 * setXXX(从1开始的占位标号，值) * 增 # # //1.注册驱动 Class.forName("com.mysql.jdbc.Driver"); //2.获取连接 Connection conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/mydb","root","root"); //3.获得预处理对象 String sql="insert into sort(sname) values(?)"; PreparedStatement stat=conn.prepareStatement(sql); //4.sql语句占位符设置实际参数 stat.setString(1,"奢侈品"); //5.执行sql语句 int line =stat.executeUpdate(); System.out.println(line); //6.释放资源 stat.close(); conn.close(); * 删 # # //1.注册驱动 Class.forName("com.mysql.jdbc.Driver"); //2.获取连接 Connection conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/mydb","root","root"); //3.获得预处理对象 String sql="delete from sort where sid=?"; PreparedStatement stat=conn.prepareStatement(sql); //4.sql语句占位符设置实际参数 stat.setInt(1,1); //5.执行sql语句 int line =stat.executeUpdate(); System.out.println(line); //6.释放资源 stat.close(); conn.close(); * 改 # # //1.注册驱动 Class.forName("com.mysql.jdbc.Driver"); //2.获取连接 Connection conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/mydb","root","root"); //3.获得预处理对象 String sql="update sort set sname=? where sid=?"; PreparedStatement stat=conn.prepareStatement(sql); //4.sql语句占位符设置实际参数 stat.setString(1,"数码产品"); stat.setInt(2,1); //5.执行sql语句 int line =stat.executeUpdate(); System.out.println(line); //6.释放资源 stat.close(); conn.close(); * 查 # # //1.注册驱动 Class.forName("com.mysql.jdbc.Driver"); //2.获取连接 Connection conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/mydb","root","root"); //3.获得预处理对象 String sql="select * from sort where sid = ?"; PreparedStatement stat=conn.prepareStatement(sql); //4.sql语句占位符设置实际参数 stat.setInt(1,1); //5.执行sql语句 ResultSet rs =stat.executeQuery(); //8.处理结果集 while(rs.next()){ String sid=rs.getString("sid"); String sname=rs.getString("Sname"); } //7.释放资源 rs.close(); stat.close(); conn.close(); ### properties ### * 使用properties文件 * 文件位置：建议放在src下 * 文件名称：任意，扩展名为.properties * 文件内容：一行一行数据，格式为key=values * 注：key自定义，value不允许为中文 * 创建配置文件 # # db.properties文件 driver=com.mysql.jdbc.Driver url=jdbc:mysql://localhost:3306/mydb user=root password=root * 加载配置文件 # # Properties props=new Properties(); Reader is = new FileReader("db.properties"); props.load(is); String driver=props.getProperty("driver"); String url=props.getProperty("url"); String user=props.getProperty("user"); String password=props.getProperty("password"); ### DBUtils ### * commons-dbutils-1.6.jar * 操作 * QueryRunner中提供对sql语句操作的API * update（Connection conn,String sql,Object... params） * query（Connection conn,String sql, ResultHandler rsh , Object... params） * ResultSetHandler接口，用于定义select操作后，怎样封装结果集 * DBUtils类，他就是一个工具类，定义了关闭资源与事务处理的方法 * QueryRunner操作 * 添加 # # publc void insert(){ try{ QueryRunner qr=new QueryRunner(); String sql="insert into student values(?)"; Object[] params={"张三"}; Connection conn=JDBCUtils.setConnection(); int line =qr.update(conn,sql,params); }catch(Exception e){ throw new RuntimeException(e); } } * 更新 # # publc void update(){ try{ QueryRunner qr=new QueryRunner(); String sql="update students set sname =? where sid=1"; Object[] params={"李四"}; Connection conn=JDBCUtils.setConnection(); int line =qr.update(conn,sql,params); }catch(Exception e){ throw new RuntimeException(e); } } * 删除 # # publc void delete(){ try{ QueryRunner qr=new QueryRunner(); String sql="delete from students where sname=?"; Object[] params={"李四"}; Connection conn=JDBCUtils.setConnection(); int line =qr.update(conn,sql,params); }catch(Exception e){ throw new RuntimeException(e); } } ### QueryRunner实现查询操作 ### * query（Connection conn,String sql,ResultSetHandler rsh,Object... params） <table style="margin-top:15px; margin-right:0px; margin-bottom:15px; margin-left:0px; padding-top:0px; padding-right:0px; padding-bottom:0px; padding-left:0px; border-top-width:0px; border-right-width:0px; border-bottom-width:0px; border-left-width:0px; border-style:initial; border-color:initial"> <thead style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:0px; padding-right:0px; padding-bottom:0px; padding-left:0px; border-top-width:0px; border-right-width:0px; border-bottom-width:0px; border-left-width:0px; border-style:initial; border-color:initial"> <tr style="margin:0px; padding:0px; border-width:1px 0px 0px; border-right-style:initial; border-bottom-style:initial; border-left-style:initial; border-right-color:initial; border-bottom-color:initial; border-left-color:initial; border-top-style:solid; border-top-color:rgb(204,204,204)"> <th style="margin:0px; padding:6px 13px; border-width:1px; border-style:solid; border-color:rgb(204,204,204)"> 方法名</th> <th style="margin:0px; padding:6px 13px; border-width:1px; border-style:solid; border-color:rgb(204,204,204)"> 解释</th> </tr> </thead> <tbody style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:0px; padding-right:0px; padding-bottom:0px; padding-left:0px; border-top-width:0px; border-right-width:0px; border-bottom-width:0px; border-left-width:0px; border-style:initial; border-color:initial"> <tr style="margin:0px; padding:0px; border-width:1px 0px 0px; border-right-style:initial; border-bottom-style:initial; border-left-style:initial; border-right-color:initial; border-bottom-color:initial; border-left-color:initial; border-top-style:solid; border-top-color:rgb(204,204,204)"> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> ArrayHandler</td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> 将结果集中的第一条记录封装到一个Object数组中，数组的每一个元素就是这条记录的每一个字段的值</td> </tr> <tr style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:0px; padding-right:0px; padding-bottom:0px; padding-left:0px; border-top-width:1px; border-right-width:0px; border-bottom-width:0px; border-left-width:0px; border-style:initial; border-color:initial; border-top-style:solid; border-top-color:rgb(204,204,204); background-color:rgb(248,248,248)"> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> ArrayListHandler</td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> 将结果中的每一条记录都封装到一个Object[]数组中，将这些到list集合中</td> </tr> <tr style="margin:0px; padding:0px; border-width:1px 0px 0px; border-right-style:initial; border-bottom-style:initial; border-left-style:initial; border-right-color:initial; border-bottom-color:initial; border-left-color:initial; border-top-style:solid; border-top-color:rgb(204,204,204)"> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> BeanHandler</td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> 将结果的第一条记录封装到一个指定的javabean中</td> </tr> <tr style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:0px; padding-right:0px; padding-bottom:0px; padding-left:0px; border-top-width:1px; border-right-width:0px; border-bottom-width:0px; border-left-width:0px; border-style:initial; border-color:initial; border-top-style:solid; border-top-color:rgb(204,204,204); background-color:rgb(248,248,248)"> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> BeanListHandler</td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> 将结果的每一条记录都封装到javabean的list集合中</td> </tr> <tr style="margin:0px; padding:0px; border-width:1px 0px 0px; border-right-style:initial; border-bottom-style:initial; border-left-style:initial; border-right-color:initial; border-bottom-color:initial; border-left-color:initial; border-top-style:solid; border-top-color:rgb(204,204,204)"> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> ColumnListHandler</td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> 将结果集中的指定的列字段值，封装到一个list集合中</td> </tr> <tr style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:0px; padding-right:0px; padding-bottom:0px; padding-left:0px; border-top-width:1px; border-right-width:0px; border-bottom-width:0px; border-left-width:0px; border-style:initial; border-color:initial; border-top-style:solid; border-top-color:rgb(204,204,204); background-color:rgb(248,248,248)"> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> ScalarHandler</td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> 它是用于单数据，例如select count（*） from student</td> </tr> </tbody> </table> * 操作 * ArrayHandler # # public void method(){ //获取QueryRunner对象、 QueryRunner qr=new QueryRunner(); //执行sql String sql="select * from students"; Object params={}; Connection conn=JDBCUtils.getConnection();\ Object[] result=qr.query(conn,sql,new ArrayHandler(),params); //处理结果集 System.out.println(Arrays.toString(result)); conn.close(); } * ArrayListHandler # # public void method(){ //获取QueryRunner对象、 QueryRunner qr=new QueryRunner(); //执行sql String sql="select * from students"; Object params={}; Connection conn=JDBCUtils.getConnection(); List<Object[]> list =qr.query(conn,sql,new ArrayListHandler(),params); //处理结果集 for(Object[] obj:list){ System.out.prinnt(Arrays.toString(obj)); } conn.close(); } * BeanHandler # # public void method(){ //获取QueryRunner对象、 QueryRunner qr=new QueryRunner(); //执行sql String sql="select * from students"; Object params={}; Connection conn=JDBCUtils.getConnection(); Student stu=qr.query(conn,sql,new BeanHandler(),params); //处理结果集 System.out.printlnz(stu); conn.close(); } * BeanListHandler # # public void method(){ //获取QueryRunner对象、 QueryRunner qr=new QueryRunner(); //执行sql String sql="select * from students"; Object params={}; Connection conn=JDBCUtils.getConnection(); List<Student> list =qr.query(conn,sql,new ArrayListHandler(),params); //处理结果集 for(Student obj:list){ System.out.prinnt(obj); } conn.close(); } * ColumnListHandler # # public void method(){ //获取QueryRunner对象、 QueryRunner qr=new QueryRunner(); //执行sql String sql="select sname from students"; Object params={}; Connection conn=JDBCUtils.getConnection(); List<String> list =qr.query(conn,sql,new ColumnListHandler(),params); //处理结果集 for(String obj:list){ System.out.prinnt(obj); } conn.close(); } * ScalarHandler # # public void method(){ //获取QueryRunner对象、 QueryRunner qr=new QueryRunner(); //执行sql String sql="select count(sname) from students"; Object params={}; Connection conn=JDBCUtils.getConnection(); int result=qr.query(conn,sql,new ScalarHandler(),params); //处理结果集 System.out.println(result); conn.close(); } ### 连接池 ### * 引入： * 实际开发中，“获得连接”，“释放资源”是非常消耗系统资源的两个过程，为了解决--引入连接池技术 * 用池来管理Connection，这样可以重复使用Connection对象，当使用完Connection时，调用close（）方法时也不会真的关闭，而是会归还。 * 规范：java为数据库连接池提供了公共的接口：javax.sql.DataSource，各个数据库厂商需要实现这些接口 * DBCP连接池 * tomcat内置连接池 * jar包 * commons-dbcp-1.4.jar * commons-pool-1.5.6.jar * 编写工具类 # # public class JDBCUtils{ public static final String DRIVER="com.mysql.jdbc.Driver" public static final String URL="jdbc.mysql://localhost:3306/mydb"; public static final String USERNAME="root"; public static final String PASSWORD="root"; /* *创建连接池BasicDataSource */ public static BasicDataSource dataSource=new BasicDataSource(); //静态代码块 static{ //对连接池对象 进行基本的配置 dataSource.setDriverClassNmae(DRIVER); dataSource.setUrl(URL); dataSource.setUsername(USERNAME); dataSource.setPassword(PASSWORD); } /* *返回连接池对象 */ public static DataSource getDataSource(){ return dataSource; } } * 工具类的使用 # # /** *获得连接池的basicdatasource传入QueryRunner中，后续的Connection则不写 */ public void method(){ //获取QueryRunner对象、 QueryRunner qr=new QueryRunner(JDBCUtils.getDataSource()); //执行sql String sql="select count(sname) from students"; Object params={}; int result=qr.query(sql,new ScalarHandler(),params); //处理结果集 System.out.println(result); conn.close(); } <table style="margin-top:15px; margin-right:0px; margin-bottom:15px; margin-left:0px; padding-top:0px; padding-right:0px; padding-bottom:0px; padding-left:0px; border-top-width:0px; border-right-width:0px; border-bottom-width:0px; border-left-width:0px; border-style:initial; border-color:initial"> <thead style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:0px; padding-right:0px; padding-bottom:0px; padding-left:0px; border-top-width:0px; border-right-width:0px; border-bottom-width:0px; border-left-width:0px; border-style:initial; border-color:initial"> <tr style="margin:0px; padding:0px; border-width:1px 0px 0px; border-right-style:initial; border-bottom-style:initial; border-left-style:initial; border-right-color:initial; border-bottom-color:initial; border-left-color:initial; border-top-style:solid; border-top-color:rgb(204,204,204)"> <th style="margin:0px; padding:6px 13px; border-width:1px; border-style:solid; border-color:rgb(204,204,204)"> 分类</th> <th style="margin:0px; padding:6px 13px; border-width:1px; border-style:solid; border-color:rgb(204,204,204)"> 属性</th> <th style="margin:0px; padding:6px 13px; border-width:1px; border-style:solid; border-color:rgb(204,204,204)"> 描述</th> </tr> </thead> <tbody style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:0px; padding-right:0px; padding-bottom:0px; padding-left:0px; border-top-width:0px; border-right-width:0px; border-bottom-width:0px; border-left-width:0px; border-style:initial; border-color:initial"> <tr style="margin:0px; padding:0px; border-width:1px 0px 0px; border-right-style:initial; border-bottom-style:initial; border-left-style:initial; border-right-color:initial; border-bottom-color:initial; border-left-color:initial; border-top-style:solid; border-top-color:rgb(204,204,204)"> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> 必须项</td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> vriverClassName</td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> 数据库驱动名称</td> </tr> <tr style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:0px; padding-right:0px; padding-bottom:0px; padding-left:0px; border-top-width:1px; border-right-width:0px; border-bottom-width:0px; border-left-width:0px; border-style:initial; border-color:initial; border-top-style:solid; border-top-color:rgb(204,204,204); background-color:rgb(248,248,248)"> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> </td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> url</td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> 数据库地址</td> </tr> <tr style="margin:0px; padding:0px; border-width:1px 0px 0px; border-right-style:initial; border-bottom-style:initial; border-left-style:initial; border-right-color:initial; border-bottom-color:initial; border-left-color:initial; border-top-style:solid; border-top-color:rgb(204,204,204)"> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> </td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> username</td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> 用户名</td> </tr> <tr style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:0px; padding-right:0px; padding-bottom:0px; padding-left:0px; border-top-width:1px; border-right-width:0px; border-bottom-width:0px; border-left-width:0px; border-style:initial; border-color:initial; border-top-style:solid; border-top-color:rgb(204,204,204); background-color:rgb(248,248,248)"> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> </td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> password</td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> 密码</td> </tr> <tr style="margin:0px; padding:0px; border-width:1px 0px 0px; border-right-style:initial; border-bottom-style:initial; border-left-style:initial; border-right-color:initial; border-bottom-color:initial; border-left-color:initial; border-top-style:solid; border-top-color:rgb(204,204,204)"> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> 基本项</td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> maxActive</td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> 最大连接数量</td> </tr> <tr style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:0px; padding-right:0px; padding-bottom:0px; padding-left:0px; border-top-width:1px; border-right-width:0px; border-bottom-width:0px; border-left-width:0px; border-style:initial; border-color:initial; border-top-style:solid; border-top-color:rgb(204,204,204); background-color:rgb(248,248,248)"> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> </td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> minldle</td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> 最小空闲连接</td> </tr> <tr style="margin:0px; padding:0px; border-width:1px 0px 0px; border-right-style:initial; border-bottom-style:initial; border-left-style:initial; border-right-color:initial; border-bottom-color:initial; border-left-color:initial; border-top-style:solid; border-top-color:rgb(204,204,204)"> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> </td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> maxldle</td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> 最大空闲连接</td> </tr> <tr style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:0px; padding-right:0px; padding-bottom:0px; padding-left:0px; border-top-width:1px; border-right-width:0px; border-bottom-width:0px; border-left-width:0px; border-style:initial; border-color:initial; border-top-style:solid; border-top-color:rgb(204,204,204); background-color:rgb(248,248,248)"> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> </td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> initialSize</td> <td style="margin-top:0px; margin-right:0px; margin-bottom:0px; margin-left:0px; padding-top:6px; padding-right:13px; padding-bottom:6px; padding-left:13px; border-top-width:1px; border-right-width:1px; border-bottom-width:1px; border-left-width:1px; border-style:initial; border-color:initial; border-top-style:solid; border-right-style:solid; border-bottom-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); border-left-color:rgb(204,204,204)"> 初始化连接</td> </tr> </tbody> </table> ### 补充 ### * 安装mysql * ![Dl0Nkly.jpg][] * 其他 * ![fg4G4T4.jpg][] [Dl0Nkly.jpg]: https://i.imgur.com/Dl0Nkly.jpg [fg4G4T4.jpg]: https://i.imgur.com/fg4G4T4.jpg
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旧城等待，
朱雀
淩亂°似流年
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