MySQL高级——综合案例
1.1 需求分析
在业务系统中,需要记录当前业务系统的访问日志,该访问日志包含:操作人,操作时间,访问类,访问方法,请求参数,请求结果,请求结果类型,请求时长 等信息。记录详细的系统访问日志,主要便于对系统中的用户请求进行追踪,并且在系统 的管理后台可以查看到用户的访问记录。
记录系统中的日志信息,可以通过Spring 框架的AOP来实现。具体的请求处理流程,如下:
1.2 搭建案例环境
1.2.1 数据库表
CREATE DATABASE mysql_demo DEFAULT CHARACTER SET utf8mb4 ; CREATE TABLE `brand` ( `id` bigint(20) NOT NULL AUTO_INCREMENT, `name` varchar(255) DEFAULT NULL COMMENT '品牌名称', `first_char` varchar(1) DEFAULT NULL COMMENT '品牌首字母', PRIMARY KEY (`id`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8; CREATE TABLE `item` ( `id` int(11) NOT NULL AUTO_INCREMENT COMMENT '商品id', `title` varchar(100) NOT NULL COMMENT '商品标题', `price` double(10,2) NOT NULL COMMENT '商品价格,单位为:元', `num` int(10) NOT NULL COMMENT '库存数量', `categoryid` bigint(10) NOT NULL COMMENT '所属类目,叶子类目', `status` varchar(1) DEFAULT NULL COMMENT '商品状态,1-正常,2-下架,3-删除', `sellerid` varchar(50) DEFAULT NULL COMMENT '商家ID', `createtime` datetime DEFAULT NULL COMMENT '创建时间', `updatetime` datetime DEFAULT NULL COMMENT '更新时间', PRIMARY KEY (`id`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8 COMMENT='商品表'; CREATE TABLE `user` ( `id` int(11) NOT NULL AUTO_INCREMENT, `username` varchar(45) NOT NULL, `password` varchar(96) NOT NULL, `name` varchar(45) NOT NULL, `birthday` datetime DEFAULT NULL, `sex` char(1) DEFAULT NULL, `email` varchar(45) DEFAULT NULL, `phone` varchar(45) DEFAULT NULL, `qq` varchar(32) DEFAULT NULL, PRIMARY KEY (`id`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8; CREATE TABLE `operation_log` ( `id` bigint(20) NOT NULL AUTO_INCREMENT COMMENT 'ID', `operate_class` varchar(200) DEFAULT NULL COMMENT '操作类', `operate_method` varchar(200) DEFAULT NULL COMMENT '操作方法', `return_class` varchar(200) DEFAULT NULL COMMENT '返回值类型', `operate_user` varchar(20) DEFAULT NULL COMMENT '操作用户', `operate_time` varchar(20) DEFAULT NULL COMMENT '操作时间', `param_and_value` varchar(500) DEFAULT NULL COMMENT '请求参数名及参数值', `cost_time` bigint(20) DEFAULT NULL COMMENT '执行方法耗时, 单位 ms', `return_value` varchar(200) DEFAULT NULL COMMENT '返回值', PRIMARY KEY (`id`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;
1.2.2 pom.xml
<properties> <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> <maven.compiler.source>1.8</maven.compiler.source> <maven.compiler.target>1.7</maven.compiler.target> <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> <maven.compiler.source>1.8</maven.compiler.source> <maven.compiler.target>1.8</maven.compiler.target> <spring.version>5.0.2.RELEASE</spring.version> <slf4j.version>1.6.6</slf4j.version> <log4j.version>1.2.12</log4j.version> <mybatis.version>3.4.5</mybatis.version> </properties> <dependencies> <!-- spring --> <dependency> <groupId>org.aspectj</groupId> <artifactId>aspectjweaver</artifactId> <version>1.6.8</version> </dependency> <dependency> <groupId>org.projectlombok</groupId> <artifactId>lombok</artifactId> <version>1.16.16</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-context</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-context-support</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-orm</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-test</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-webmvc</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-tx</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>junit</groupId> <artifactId>junit</artifactId> <version>4.12</version> <scope>test</scope> </dependency> <dependency> <groupId>javax.servlet</groupId> <artifactId>javax.servlet-api</artifactId> <version>3.1.0</version> <scope>provided</scope> </dependency> <dependency> <groupId>javax.servlet.jsp</groupId> <artifactId>jsp-api</artifactId> <version>2.0</version> <scope>provided</scope> </dependency> <dependency> <groupId>log4j</groupId> <artifactId>log4j</artifactId> <version>${log4j.version}</version> </dependency> <dependency> <groupId>org.mybatis</groupId> <artifactId>mybatis</artifactId> <version>${mybatis.version}</version> </dependency> <dependency> <groupId>org.mybatis</groupId> <artifactId>mybatis-spring</artifactId> <version>1.3.0</version> </dependency> <dependency> <groupId>c3p0</groupId> <artifactId>c3p0</artifactId> <version>0.9.1.2</version> </dependency> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <version>5.1.5</version> </dependency> <dependency> <groupId>com.fasterxml.jackson.core</groupId> <artifactId>jackson-core</artifactId> <version>2.9.0</version> </dependency> <dependency> <groupId>com.fasterxml.jackson.core</groupId> <artifactId>jackson-databind</artifactId> <version>2.9.0</version> </dependency> <dependency> <groupId>com.fasterxml.jackson.core</groupId> <artifactId>jackson-annotations</artifactId> <version>2.9.0</version> </dependency> </dependencies><build> <plugins> <plugin> <groupId>org.apache.tomcat.maven</groupId> <artifactId>tomcat7-maven-plugin</artifactId> <version>2.2</version> <configuration> <port>8080</port> <path>/</path> <uriEncoding>utf-8</uriEncoding> </configuration> </plugin> </plugins> </build>
1.2.3 web.xml
<?xml version="1.0" encoding="UTF-8"?> <web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" version="2.5"> <!-- 解决post乱码 --> <filter> <filter-name>CharacterEncodingFilter</filter-name> <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class> <init-param> <param-name>encoding</param-name> <param-value>utf-8</param-value> </init-param> <init-param> <param-name>forceEncoding</param-name> <param-value>true</param-value> </init-param> </filter> <filter-mapping> <filter-name>CharacterEncodingFilter</filter-name> <url-pattern>/*</url-pattern> </filter-mapping> <context-param> <param-name>contextConfigLocation</param-name> <param-value>classpath:applicationContext.xml</param-value> </context-param> <listener> <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class> </listener> <servlet> <servlet-name>springmvc</servlet-name> <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class> <!-- 指定加载的配置文件 ,通过参数contextConfigLocation加载--> <init-param> <param-name>contextConfigLocation</param-name> <param-value>classpath:springmvc.xml</param-value> </init-param> </servlet> <servlet-mapping> <servlet-name>springmvc</servlet-name> <url-pattern>*.do</url-pattern> </servlet-mapping> <welcome-file-list> <welcome-file>log-datalist.html</welcome-file> </welcome-file-list> </web-app>
1.2.4 db.properties
jdbc.driver=com.mysql.jdbc.Driver jdbc.url=jdbc:mysql://192.168.142.128:3306/mysql_demo jdbc.username=root jdbc.password=itcast
1.2.5 applicationContext.xml
<?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:aop="http://www.springframework.org/schema/aop" xmlns:tx="http://www.springframework.org/schema/tx" xmlns:context="http://www.springframework.org/schema/context" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd"> <!-- 加载配置文件 --> <context:property-placeholder location="classpath:db.properties"/> <!-- 配置 spring 创建容器时要扫描的包 --> <context:component-scan base-package="cn.itcast"> <context:exclude-filter type="annotation" expression="org.springframework.stereotype.Controller"> </context:exclude-filter> </context:component-scan> <!-- 配置 MyBatis 的 Session 工厂 --> <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean"> <property name="dataSource" ref="dataSource"/> <property name="typeAliasesPackage" value="cn.itcast.pojo"/> </bean> <!-- 配置数据源 --> <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource"> <property name="driverClass" value="${jdbc.driver}"></property> <property name="jdbcUrl" value="${jdbc.url}"></property> <property name="user" value="${jdbc.username}"></property> <property name="password" value="${jdbc.password}"></property> </bean> <!-- 配置 Mapper 扫描器 --> <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer"> <property name="basePackage" value="cn.itcast.mapper"/> </bean> <!-- 配置事务管理器 --> <bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager"> <property name="dataSource" ref="dataSource"/> </bean> <!-- 配置事务的注解驱动 --> <tx:annotation-driven transaction-manager="transactionManager"></tx:annotation-driven> </beans>
com.mchange.v2.c3p0.ComboPooledDataSource:数据库连接池的一种
C3P0是一个开放源代码的JDBC连接池,它在lib目录中与Hibernate一起发布,包括了实现jdbc3和jdbc2扩展规范说明的Connection 和Statement 池的DataSources 对象。
1.2.6 springmvc.xml
<?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:mvc="http://www.springframework.org/schema/mvc" xmlns:context="http://www.springframework.org/schema/context" xmlns:aop="http://www.springframework.org/schema/aop" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd"> <context:component-scan base-package="cn.itcast.controller"></context:component-scan><mvc:annotation-driven></mvc:annotation-driven><aop:aspectj-autoproxy /></beans>
1.2.7 导入基础工程
1.3 通过AOP记录操作日志
1.3.1 自定义注解
通过自定义注解,来标示方法需不需要进行记录日志,如果该方法在访问时需要记录日志,则在该方法上标示该注解既可。
@Inherited @Documented @Target(ElementType.METHOD) @Retention(RetentionPolicy.RUNTIME) public @interface OperateLog { }
1.3.2 定义通知类
@Component @Aspect public class OperateAdvice { private static Logger log = Logger.getLogger(OperateAdvice.class); @Autowired private OperationLogService operationLogService; //指定切入点为:定义在 controller 包里的任意类的任意方法。 @Around("execution(* cn.itcast.controller.*.*(..)) && @annotation(operateLog)") public Object insertLogAround(ProceedingJoinPoint pjp , OperateLog operateLog) throws Throwable{ System.out.println(" ************************ 记录日志 [start] ****************************** "); OperationLog op = new OperationLog(); DateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss"); op.setOperateTime(sdf.format(new Date())); op.setOperateUser(DataUtils.getRandStr(8)); op.setOperateClass(pjp.getTarget().getClass().getName()); op.setOperateMethod(pjp.getSignature().getName()); //获取方法调用时传递的参数 Object[] args = pjp.getArgs(); op.setParamAndValue(Arrays.toString(args)); long start_time = System.currentTimeMillis(); //放行 Object object = pjp.proceed(); long end_time = System.currentTimeMillis(); op.setCostTime(end_time - start_time); if(object != null){ op.setReturnClass(object.getClass().getName()); op.setReturnValue(object.toString()); }else{ op.setReturnClass("java.lang.Object"); op.setParamAndValue("void"); } log.error(JsonUtils.obj2JsonString(op)); operationLogService.insert(op); System.out.println(" ************************** 记录日志 [end] *************************** "); return object; } }
1.3.3 方法上加注解
在需要记录日志的方法上加上注解@OperateLog。
@OperateLog @RequestMapping("/insert") public Result insert(@RequestBody Brand brand){ try { brandService.insert(brand); return new Result(true,"操作成功"); } catch (Exception e) { e.printStackTrace(); return new Result(false,"操作失败"); } }
1.4 日志查询后端代码实现
1.4.1 Mapper接口
public interface OperationLogMapper { public void insert(OperationLog operationLog); public List<OperationLog> selectListByCondition(Map dataMap); public Long countByCondition(Map dataMap); }
1.4.2 Mapper.xml 映射配置文件
<?xml version="1.0" encoding="UTF-8" ?> <!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd" > <mapper namespace="cn.itcast.mapper.OperationLogMapper" > <insert id="insert" parameterType="operationLog"> INSERT INTO operation_log(id,return_value,return_class,operate_user,operate_time,param_and_value, operate_class,operate_method,cost_time) VALUES(NULL,#{returnValue},#{returnClass},#{operateUser},#{operateTime},#{paramAndValue}, #{operateClass},#{operateMethod},#{costTime}) </insert> <select id="selectListByCondition" parameterType="map" resultType="operationLog"> select id , operate_class as operateClass , operate_method as operateMethod, return_class as returnClass, operate_user as operateUser, operate_time as operateTime, param_and_value as paramAndValue, cost_time as costTime, return_value as returnValue from operation_log <include refid="oplog_where"/> limit #{start},#{size} </select> <select id="countByCondition" resultType="long" parameterType="map"> select count(*) from operation_log <include refid="oplog_where"/> </select> <sql id="oplog_where"> <where> <if test="operateClass != null and operateClass != '' "> and operate_class = #{operateClass} </if> <if test="operateMethod != null and operateMethod != '' "> and operate_method = #{operateMethod} </if> <if test="returnClass != null and returnClass != '' "> and return_class = #{returnClass} </if> <if test="costTime != null"> and cost_time = #{costTime} </if> </where> </sql> </mapper>
1.4.3 Service
@Service @Transactional public class OperationLogService { //private static Logger logger = Logger.getLogger(OperationLogService.class); @Autowired private OperationLogMapper operationLogMapper; //插入数据 public void insert(OperationLog operationLog){ operationLogMapper.insert(operationLog); } //根据条件查询 public PageResult selectListByCondition(Map dataMap, Integer pageNum , Integer pageSize){ if(paramMap ==null){ paramMap = new HashMap(); } paramMap.put("start" , (pageNum-1)*rows); paramMap.put("rows",rows); Object costTime = paramMap.get("costTime"); if(costTime != null){ if("".equals(costTime.toString())){ paramMap.put("costTime",null); }else{ paramMap.put("costTime",new Long(paramMap.get("costTime").toString())); } } System.out.println(dataMap); long countStart = System.currentTimeMillis(); Long count = operationLogMapper.countByCondition(dataMap); long countEnd = System.currentTimeMillis(); System.out.println("Count Cost Time : " + (countEnd-countStart)+" ms"); List<OperationLog> list = operationLogMapper.selectListByCondition(dataMap); long queryEnd = System.currentTimeMillis(); System.out.println("Query Cost Time : " + (queryEnd-countEnd)+" ms"); return new PageResult(count,list); } }
1.4.4 Controller
@RestController @RequestMapping("/operationLog") public class OperationLogController { @Autowired private OperationLogService operationLogService; @RequestMapping("/findList") public PageResult findList(@RequestBody Map dataMap, Integer pageNum , Integer pageSize){ PageResult page = operationLogService.selectListByCondition(dataMap, pageNum, pageSize); return page; } }
2.5 日志查询前端代码实现
前端代码使用 BootStrap + AdminLTE 进行布局, 使用Vuejs 进行视图层展示。
2.5.1 js
<script> var vm = new Vue({ el: '#app', data: { dataList:[], searchEntity:{ operateClass:'', operateMethod:'', returnClass:'', costTime:'' }, page: 1, //显示的是哪一页 pageSize: 10, //每一页显示的数据条数 total: 150, //记录总数 maxPage:8 //最大页数 }, methods: { pageHandler: function (page) { this.page = page; this.search(); }, search: function () { var _this = this; this.showLoading(); axios.post('/operationLog/findList.do?pageNum=' + _this.page + "&pageSize=" + _this.pageSize, _this.searchEntity).then(function (response) { if (response) { _this.dataList = response.data.dataList; _this.total = response.data.total; _this.hideLoading(); } }) }, showLoading: function () { $('#loadingModal').modal({backdrop: 'static', keyboard: false}); }, hideLoading: function () { $('#loadingModal').modal('hide'); }, }, created:function(){ this.pageHandler(1); } }); </script>
1.5.2 列表数据展示
<tr v-for="item in dataList"> <td><input name="ids" type="checkbox"></td> <td>{{item.id}}</td> <td>{{item.operateClass}}</td> <td>{{item.operateMethod}}</td> <td>{{item.returnClass}}</td> <td>{{item.returnValue}}</td> <td>{{item.operateUser}}</td> <td>{{item.operateTime}}</td> <td>{{item.costTime}}</td> <td class="text-center"> <button type="button" class="btn bg-olive btn-xs">详情</button> <button type="button" class="btn bg-olive btn-xs">删除</button> </td> </tr>
1.5.3 分页插件
<div class="wrap" id="wrap"> <zpagenav v-bind:page="page" v-bind:page-size="pageSize" v-bind:total="total" v-bind:max-page="maxPage" v-on:pagehandler="pageHandler"> </zpagenav> </div>
1.6 联调测试
可以通过postman来访问业务系统,再查看数据库中的日志信息,验证能不能将用户的访问日志记录下来。
1.7 分析性能问题
系统中用户访问日志的数据量,随着时间的推移,这张表的数据量会越来越大,因此我们需要根据业务需求,来对日志查询模块的性能进行优化。
1) 分页查询优化
由于在进行日志查询时,是进行分页查询,那也就意味着,在查看时,至少需要查询两次:
A. 查询符合条件的总记录数。--> count 操作
B. 查询符合条件的列表数据。--> 分页查询 limit 操作
通常来说,count() 都需要扫描大量的行(意味着需要访问大量的数据)才能获得精确的结果,因此是很难对该SQL进行优化操作的。如果需要对count进行优化,可以采用另外一种思路,可以增加汇总表,或者redis缓存来专门记录该表对应的记录数,这样的话,就可以很轻松的实现汇总数据的查询,而且效率很高,但是这种统计并不能保证百分之百的准确 。对于数据库的操作,“快速、精确、实现简单”,三者永远只能满足其二,必须舍掉其中一个。
2) 条件查询优化
针对于条件查询,需要对查询条件,及排序字段建立索引。
3) 读写分离
通过主从复制集群,来完成读写分离,使写操作走主节点, 而读操作,走从节点。
4) MySQL服务器优化
5) 应用优化
1.8 性能优化 - 分页
1.8.1 优化count
创建一张表用来记录日志表的总数据量:
create table log_counter( logcount bigint not null )engine = innodb default CHARSET = utf8;
在每次插入数据之后,更新该表 :
<update id="updateLogCounter" > update log_counter set logcount = logcount + 1 </update>
在进行分页查询时, 获取总记录数,从该表中查询既可。
<select id="countLogFromCounter" resultType="long"> select logcount from log_counter limit 1 </select>
1.8.2 优化 limit
在进行分页时,一般通过创建覆盖索引,能够比较好的提高性能。一个非常常见,而又非常头疼的分页场景就是 "limit 1000000,10" ,此时MySQL需要搜索出前1000010 条记录后,仅仅需要返回第 1000001 到 1000010 条记录,前1000000 记录会被抛弃,查询代价非常大。
当点击比较靠后的页码时,就会出现这个问题,查询效率非常慢。
优化SQL:
select * from operation_log limit 3000000 , 10;
将上述SQL优化为 :
select * from operation_log t , (select id from operation_log order by id limit 3000000,10) b where t.id = b.id ; <select id="selectListByCondition" parameterType="map" resultType="operationLog"> select id , operate_class as operateClass , operate_method as operateMethod, return_class as returnClass, operate_user as operateUser, operate_time as operateTime, param_and_value as paramAndValue, cost_time as costTime, return_value as returnValue from operation_log t, (select id from operation_log <where> <include refid="oplog_where"/> </where> order by id limit #{start},#{rows}) b where t.id = b.id </select>
1.9 性能优化 - 索引
当根据操作人进行查询时, 查询的效率很低,耗时比较长。原因就是因为在创建数据库表结构时,并没有针对于 操作人 字段建立索引。
CREATE INDEX idx_user_method_return_cost ON operation_log(operate_user,operate_method,return_class,cost_time);
同上 , 为了查询效率高,我们也需要对 操作方法、返回值类型、操作耗时 等字段进行创建索引,以提高查询效率。
CREATE INDEX idx_optlog_method_return_cost ON operation_log(operate_method,return_class,cost_time); CREATE INDEX idx_optlog_return_cost ON operation_log(return_class,cost_time); CREATE INDEX idx_optlog_cost ON operation_log(cost_time);
1.10 性能优化 - 排序
在查询数据时,如果业务需求中需要我们对结果内容进行了排序处理 , 这个时候,我们还需要对排序的字段建立适当的索引, 来提高排序的效率 。
1.11 性能优化 - 读写分离
1.11.1 概述
在Mysql主从复制的基础上,可以使用读写分离来降低单台Mysql节点的压力,从而来提高访问效率,读写分离的架构如下:
对于读写分离的实现,可以通过Spring AOP 来进行动态的切换数据源,进行操作 :
1.11.2 实现方式
db.properties
jdbc.write.driver=com.mysql.jdbc.Driver jdbc.write.url=jdbc:mysql://192.168.142.128:3306/mysql_demo jdbc.write.username=root jdbc.write.password=itcast jdbc.read.driver=com.mysql.jdbc.Driver jdbc.read.url=jdbc:mysql://192.168.142.129:3306/mysql_demo jdbc.read.username=root jdbc.read.password=itcast
applicationContext-datasource.xml
<?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:aop="http://www.springframework.org/schema/aop" xmlns:tx="http://www.springframework.org/schema/tx" xmlns:context="http://www.springframework.org/schema/context" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd"> <!-- 配置数据源 - Read --> <bean id="readDataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource" destroy-method="close" lazy-init="true"> <property name="driverClass" value="${jdbc.read.driver}"></property> <property name="jdbcUrl" value="${jdbc.read.url}"></property> <property name="user" value="${jdbc.read.username}"></property> <property name="password" value="${jdbc.read.password}"></property> </bean> <!-- 配置数据源 - Write --> <bean id="writeDataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource" destroy-method="close" lazy-init="true"> <property name="driverClass" value="${jdbc.write.driver}"></property> <property name="jdbcUrl" value="${jdbc.write.url}"></property> <property name="user" value="${jdbc.write.username}"></property> <property name="password" value="${jdbc.write.password}"></property> </bean> <!-- 配置动态分配的读写 数据源 --> <bean id="dataSource" class="cn.itcast.aop.datasource.ChooseDataSource" lazy-init="true"> <property name="targetDataSources"> <map key-type="java.lang.String" value-type="javax.sql.DataSource"> <entry key="write" value-ref="writeDataSource"/> <entry key="read" value-ref="readDataSource"/> </map> </property> <property name="defaultTargetDataSource" ref="writeDataSource"/> <property name="methodType"> <map key-type="java.lang.String"> <entry key="read" value=",get,select,count,list,query,find"/> <entry key="write" value=",add,create,update,delete,remove,insert"/> </map> </property> </bean> </beans>
ChooseDataSource
public class ChooseDataSource extends AbstractRoutingDataSource { public static Map<String, List<String>> METHOD_TYPE_MAP = new HashMap<String, List<String>>(); /** * 实现父类中的抽象方法,获取数据源名称 * @return */ protected Object determineCurrentLookupKey() { return DataSourceHandler.getDataSource(); } // 设置方法名前缀对应的数据源 public void setMethodType(Map<String, String> map) { for (String key : map.keySet()) { List<String> v = new ArrayList<String>(); String[] types = map.get(key).split(","); for (String type : types) { if (!StringUtils.isEmpty(type)) { v.add(type); } } METHOD_TYPE_MAP.put(key, v); } System.out.println("METHOD_TYPE_MAP : "+METHOD_TYPE_MAP); } }
DataSourceHandler
public class DataSourceHandler { // 数据源名称 public static final ThreadLocal<String> holder = new ThreadLocal<String>(); /** * 在项目启动的时候将配置的读、写数据源加到holder中 */ public static void putDataSource(String datasource) { holder.set(datasource); } /** * 从holer中获取数据源字符串 */ public static String getDataSource() { return holder.get(); } }
DataSourceAspect
@Aspect @Component @Order(-9999) @EnableAspectJAutoProxy(proxyTargetClass = true) public class DataSourceAspect { protected Logger logger = LoggerFactory.getLogger(this.getClass()); /** * 配置前置通知,使用在方法aspect()上注册的切入点 */ @Before("execution(* cn.itcast.service.*.*(..))") @Order(-9999) public void before(JoinPoint point) { String className = point.getTarget().getClass().getName(); String method = point.getSignature().getName(); logger.info(className + "." + method + "(" + Arrays.asList(point.getArgs())+ ")"); try { for (String key : ChooseDataSource.METHOD_TYPE_MAP.keySet()) { for (String type : ChooseDataSource.METHOD_TYPE_MAP.get(key)) { if (method.startsWith(type)) { System.out.println("key : " + key); DataSourceHandler.putDataSource(key); break; } } } } catch (Exception e) { e.printStackTrace(); } } }
通过 @Order(-9999) 注解来控制事务管理器, 与该通知类的加载顺序 , 需要让通知类 , 先加载 , 来判定使用哪个数据源 .
1.11.3 验证
在主库和从库中,执行如下SQL语句,来查看是否读的时候, 从从库中读取 ; 写入操作的时候,是否写入到主库。
show status like 'Innodb_rows_%' ;
1.11.4 原理
1.12 性能优化 - 应用优化
1.12.1 缓存
可以在业务系统中使用redis来做缓存,缓存一些基础性的数据,来降低关系型数据库的压力,提高访问效率。
1.12.2 全文检索
如果业务系统中的数据量比较大(达到千万级别),这个时候,如果再对数据库进行查询,特别是进行分页查询,速度将变得很慢(因为在分页时首先需要count求合计数),为了提高访问效率,这个时候,可以考虑加入Solr 或者 ElasticSearch全文检索服务,来提高访问效率。
1.13.3 非关系数据库
也可以考虑将非核心(重要)数据,存在 MongoDB 中,这样可以提高插入以及查询的效率。