spring-mybatis-data-common程序级分表操作实例

spring-mybatis-data-common-2.0新增分表机制,在1.0基础上做了部分调整.

基于机架展示分库应用
数据库分表实力创建

create table tb_example_1(

  id bigint primary key auto_increment ,

  eId bigint,

  exampleName varchar(40),

  exampleTitle varchar(200),

  exampleDate datetime

)ENGINE=MyISAM  DEFAULT CHARSET=utf8 AUTO_INCREMENT=1 ;  

create table tb_example_2 like tb_example_1;

create table tb_example_3 like tb_example_1;

create table tb_example(

  id bigint primary key auto_increment ,

  eId bigint,

  exampleName varchar(40),

  exampleTitle varchar(200),

  exampleDate datetime

)ENGINE=MERGE UNION=(tb_example_1,tb_example_2,tb_example_3) INSERT_METHOD=LAST AUTO_INCREMENT=1 ;

程序构建分表操作
1.spring-mybatis-common-data中提供了com.spring.mybatis.data.common.model.ExampleModel用于Demo的实体类
添加maven依赖

<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/maven-v4_0_0.xsd">

    <modelVersion>4.0.0</modelVersion>

    <groupId>com.spring.mybatis</groupId>

    <artifactId>com-spring-mybatis-common-data-demo</artifactId>

    <packaging>war</packaging>

    <version>0.0.1-SNAPSHOT</version>

    <name>com-spring-mybatis-common-data-demo Maven Webapp</name>

    <url>http://maven.apache.org</url>

    <properties>

        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>

        <spring.mybatis.data.version>2.0</spring.mybatis.data.version>

        <junit.version>4.11</junit.version>

    </properties>

    <dependencies>

        <!-- spring-mybatis-data-common begin -->

        <dependency>

            <groupId>com.spring.mybatis</groupId>

            <artifactId>spring-mybatis-data-common</artifactId>

            <version>${spring.mybatis.data.version}</version>

        </dependency>

        <!-- spring-mybatis-data-common end -->

        <dependency>

            <groupId>junit</groupId>

            <artifactId>junit</artifactId>

            <version>${junit.version}</version>

            <scope>test</scope>

        </dependency>

        <dependency>

            <groupId>com.alibaba</groupId>

            <artifactId>druid</artifactId>

            <version>0.2.26</version>

        </dependency>

        <dependency>

            <groupId>mysql</groupId>

            <artifactId>mysql-connector-java</artifactId>

            <version>5.1.1</version>

        </dependency>

        <dependency>

            <groupId>org.codehaus.jackson</groupId>

            <artifactId>jackson-mapper-asl</artifactId>

            <version>1.9.13</version>

        </dependency>

    </dependencies>

    <build>

        <finalName>com-spring-mybatis-common-data-demo</finalName>

    </build>

</project>

2.持久层继承分表Dao接口,也可以自己定义

@Repository

public interface ExampleModelDao extends ShardCudDao<ExampleModel>,ShardReadDao<ExampleModel>{

    /**get common base table max auto_increment id*/

    public Long selectMaxId() throws DaoException;

}

在持久层自定义了一个selectMaxId()用于多个分表共享同一个自增策略,这里采用程序级别控制
3.业务层继承分表,业务层操作可以自定义,也可以继承com.spring.mybatis.data.common.service.BaseService中提供的常规业务

@Service

public class ExampleModelService extends BaseShard{

    @Autowired

    private ExampleModelDao exampleModelDao;

    @Override

    public String getBaseShardTableName() {

        return "tb_example_";

    }

    @Override

    public int getShardTableCount() {

        return 3;

    }

    public int deleteObject(ExampleModel entity) throws ServiceException {

        try {

            return this.exampleModelDao.delete(getShardTableName(entity.geteId()+"", 1), entity.getId());

        } catch (DaoException e) {

            e.printStackTrace();

        }

        return 0;

    }

    public int save(ExampleModel entity) throws ServiceException {

        long mxId = 1;

        try {

            Long maxId = this.exampleModelDao.selectMaxId();

            if(null != maxId && maxId >= 1){

                mxId = maxId + 1;

            }

        } catch (DaoException e) {

            LogUtils.dao.error("insert exampleModel before get Max Id error.",e);

            e.printStackTrace();

        }

        try {

            entity.setId(mxId);

            return this.exampleModelDao.insert(getShardTableName(entity.geteId()+"", 1), entity);

        } catch (DaoException e) {

            LogUtils.dao.error("insert exampleModel to table " + getShardTableName(entity.geteId()+"", 1) + " error");

            e.printStackTrace();

        }

        return 0;

    }

    public ExampleModel selectObject(ExampleModel entity)

            throws ServiceException {

        try {

            return this.exampleModelDao.selectById(getShardTableName(entity.geteId()+"", 1), entity.geteId());

        } catch (DaoException e) {

            e.printStackTrace();

        }

        return null;

    }

    public void setExampleModelDao(ExampleModelDao exampleModelDao) {

        this.exampleModelDao = exampleModelDao;

    }

}

BaseShard是一个抽象类,继承它需要实现两个方法.

    /**

     * get shard table count

     * @return

     */

    public abstract int getShardTableCount();

    /**

     * get base shard name

     * @return

     */

    public abstract String getBaseShardTableName();

getShardTableCount()用于返回分表数量, public abstract String getBaseShardTableName()用于返回分表表名统一前缀.
如实例中的分表为tb_example、tb_example_1、tb_example_2、tb_example_3,分表表名前缀为"tb_example_",分表数量为3.
BaseShard中获取映射表名的操作

    /**

     * get shard table name <br>

     *

     * shard table index start with 0

     *

     * just like follows

     *

     * tb_example_0

     * tb_example_1

     * tb_example_2

     * tb_example_3

     *

     * @param tableName

     * @return

     */

    public String getShardTableName(String shardKey);

    /**

     * get shard table name <br>

     *

     * shard table index start with (0+baseNumber)

     *

     * just like follows

     *

     * tb_example_(0+baseNumber)

     * tb_example_(1+baseNumber)

     * tb_example_(2+baseNumber)

     * tb_example_(3+baseNumber)

     *

     *

     * @param shardKey

     * @param baseNumber

     * @return

     */

    public String getShardTableName(String shardKey,int baseNumber);

4.持久层实现

<?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="com.spring.mybatis.common.data.demo.dao">

  <!--insert entity-->

  <insert id="insert" parameterType="exampleModel" flushCache="true">

      INSERT INTO ${tablename}(

            id,

            eId,

            exampleName,

            exampleTitle,

            exampleDate)

    VALUES(

        #{object.id},

        #{object.eId},

        #{object.exampleName},

        #{object.exampleTitle},

        #{object.exampleDate}

    )

  </insert>

  <select id="selectMaxId" resultType="long">

          select max(id) from tb_example

  </select>

  <delete id="delete" parameterType="long" flushCache="true">

      DELETE FROM

          ${tablename}

      WHERE

          id=#{id}

  </delete>

  <select id="selectById" parameterType="long" resultType="exampleModel">

      SELECT

          id AS id,eId AS eId,exampleName AS exampleName,exampleTitle AS exampleTitle,exampleDate AS exampleDate

      FROM

          ${tablename}

      WHERE

          id=#{id}

  </select>

</mapper>

程序运行结果

查询各个分表

实例下载: http://files.cnblogs.com/dennisit/spring-mybatis-data-common-2.0-and-demo.7z

转载请注明地址:[http://www.cnblogs.com/dennisit/p/3793501.html]

巴特西

spring-mybatis-data-common程序级分表操作实例

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