spring实现多数据源切换示例讲解
多数据源切换的使用场景
多数据源的使用场景可能有很多,比如我们的业务数量很比较多,需要做分库的时候,多个数据库的读写操作就是一个多数据源的读写操作。自己单位的项目由于数据量较大,起初就选择了阿里的DRDS分库系统,但由于sql语句的兼容性问题并且阿里是收费的,CTO要求我们自己实现分库系统。因为我们的产品是服务于企业的,所以就使用企业的ID作为一个key,然后对key取余这个一个常规算法,将企业的数据分散在不同的数据库实例上,从而实现数据分库。接下来,写一个如何实现动态切换数据的项目,来学习一下AbstractRoutingDataSource抽象类的使用。
以下所说的“连接池”等价于“数据源” ,两种说法可以互相替换理解
maven坐标
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.alex</groupId>
<artifactId>spring</artifactId>
<version>1.0-SNAPSHOT</version>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
<java.version>1.8</java.version>
<jweb.version>1.1.3</jweb.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-beans</artifactId>
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<dependency>
<groupId>org.springframework</groupId>
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<dependency>
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<dependency>
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<dependency>
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<dependency>
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<dependency>
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<dependency>
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<dependency>
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<dependency>
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