java 项目分库分表技术选型

第一步、安装jdk（mycat需要jre运行环境）

1、jdk安装教程：

第二步、安装mycat

1、下载地址：http://dl.mycat.org.cn/1.6.7.6/20210303094759/

2、上传到服务器进行解压，所有内容会生成mycat文件夹

 解压命令：tar -xzvf Mycat-server-1.6.7.6-release-20210303094759-linux.tar.gz

3、配置分库分表

  a)   /usr/local/mycat/conf/schema.xml

<?xml version="1.0"?>
<!DOCTYPE mycat:schema SYSTEM "schema.dtd">
<mycat:schema xmlns:mycat="http://io.mycat/">

	<schema name="testdb" checkSQLschema="false" sqlMaxLimit="100" >
		<!-- auto sharding by id (long) -->
		<!--splitTableNames 启用<table name 属性使用逗号分割配置多个表,即多个表使用这个配置-->
<!--fetchStoreNodeByJdbc 启用ER表使用JDBC方式获取DataNode-->
   <!--逻辑数据表tb_test--> 
        <!--rule="sharding-by-murmur"  使用随机拆分 -->
    <table name="tb_test" primaryKey="id" dataNode="dn1,dn2,dn3" rule="sharding-by-murmur" />
		<!-- <table name="oc_call" primaryKey="ID" dataNode="dn1$0-743" rule="latest-month-calldate"
			/> -->
	</schema>
	<!-- <dataNode name="dn1$0-743" dataHost="localhost1" database="db$0-743"
		/> -->
	<dataNode name="dn1" dataHost="localhost1" database="db1" />
	<dataNode name="dn2" dataHost="localhost1" database="db2" />
	<dataNode name="dn3" dataHost="localhost1" database="db3" />
	<!--<dataNode name="dn4" dataHost="sequoiadb1" database="SAMPLE" />
	 <dataNode name="jdbc_dn1" dataHost="jdbchost" database="db1" />
	<dataNode	name="jdbc_dn2" dataHost="jdbchost" database="db2" />
	<dataNode name="jdbc_dn3" 	dataHost="jdbchost" database="db3" /> -->
	<dataHost name="localhost1" maxCon="1000" minCon="10" balance="0"
			  writeType="0" dbType="mysql" dbDriver="jdbc" switchType="1"  slaveThreshold="100">
		<heartbeat>select user()</heartbeat>
		<!-- can have multi write hosts -->
		<writeHost host="hostM1" url="jdbc:mysql://192.168.223.131:3306?useSSL=false&serverTimezone=UTC" user="wangru" password="1qaz@WSX">
		</writeHost>
		<!-- <writeHost host="hostM2" url="localhost:3316" user="root" password="123456"/> -->
	
</mycat:schema>

b)   /usr/local/mycat/conf/server.xml

<?xml version="1.0" encoding="UTF-8"?>
<!-- - - Licensed under the Apache License, Version 2.0 (the "License"); 
	- you may not use this file except in compliance with the License. - You 
	may obtain a copy of the License at - - http://www.apache.org/licenses/LICENSE-2.0 
	- - Unless required by applicable law or agreed to in writing, software - 
	distributed under the License is distributed on an "AS IS" BASIS, - WITHOUT 
	WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. - See the 
	License for the specific language governing permissions and - limitations 
	under the License. -->
<!DOCTYPE mycat:server SYSTEM "server.dtd">
<mycat:server xmlns:mycat="http://io.mycat/">
	<system>
	<property name="nonePasswordLogin">0</property> <!-- 0为需要密码登陆、1为不需要密码登陆 ,默认为0，设置为1则需要指定默认账户-->
	<property name="ignoreUnknownCommand">0</property><!-- 0遇上没有实现的报文(Unknown command:),就会报错、1为忽略该报文，返回ok报文。
	在某些mysql客户端存在客户端已经登录的时候还会继续发送登录报文,mycat会报错,该设置可以绕过这个错误-->
	<property name="useHandshakeV10">1</property>
    <property name="removeGraveAccent">1</property>
	<property name="useSqlStat">0</property>  <!-- 1为开启实时统计、0为关闭 -->
	<property name="useGlobleTableCheck">0</property>  <!-- 1为开启全加班一致性检测、0为关闭 -->
	<property name="sqlExecuteTimeout">300</property>  <!-- SQL 执行超时 单位:秒-->
		<property name="sequenceHandlerType">1</property>
	<!--<property name="sequnceHandlerPattern">(?:(\s*next\s+value\s+for\s*MYCATSEQ_(\w+))(,|\)|\s)*)+</property>
	INSERT INTO `travelrecord` (`id`,user_id) VALUES ('next value for MYCATSEQ_GLOBAL',"xxx");
	-->
	<!--必须带有MYCATSEQ_或者 mycatseq_进入序列匹配流程 注意MYCATSEQ_有空格的情况-->
	<property name="sequnceHandlerPattern">(?:(\s*next\s+value\s+for\s*MYCATSEQ_(\w+))(,|\)|\s)*)+</property>
	<property name="subqueryRelationshipCheck">false</property> <!-- 子查询中存在关联查询的情况下,检查关联字段中是否有分片字段 .默认 false -->
	<property name="sequenceHanlderClass">io.mycat.route.sequence.handler.HttpIncrSequenceHandler</property>
      <!--  <property name="useCompression">1</property>--> <!--1为开启mysql压缩协议-->
        <!--  <property name="fakeMySQLVersion">5.6.20</property>--> <!--设置模拟的MySQL版本号-->
	<!-- <property name="processorBufferChunk">40960</property> -->
	<!-- 
	<property name="processors">1</property> 
	<property name="processorExecutor">32</property> 
	 -->
        <!--默认为type 0: DirectByteBufferPool | type 1 ByteBufferArena | type 2 NettyBufferPool -->
		<property name="processorBufferPoolType">0</property>
		<!--默认是65535 64K 用于sql解析时最大文本长度 -->
		<!--<property name="maxStringLiteralLength">65535</property>-->
		<!--<property name="sequenceHandlerType">0</property>-->
		<!--<property name="backSocketNoDelay">1</property>-->
		<!--<property name="frontSocketNoDelay">1</property>-->
		<!--<property name="processorExecutor">16</property>-->
		<!--
			<property name="serverPort">8066</property>
			<property name="managerPort">9066</property>
			<property name="idleTimeout">300000</property>
			<property name="authTimeout">15000</property>
			<property name="bindIp">0.0.0.0</property>
			<property name="dataNodeIdleCheckPeriod">300000</property> 5 * 60 * 1000L; //连接空闲检查
			<property name="frontWriteQueueSize">4096</property> <property name="processors">32</property> -->
		<!--分布式事务开关，0为不过滤分布式事务，1为过滤分布式事务（如果分布式事务内只涉及全局表，则不过滤），2为不过滤分布式事务,但是记录分布式事务日志-->
		<property name="handleDistributedTransactions">0</property>
		
			<!--
			off heap for merge/order/group/limit      1开启   0关闭
		-->
		<property name="useOffHeapForMerge">0</property>

		<!--
			单位为m
		-->
        <property name="memoryPageSize">64k</property>

		<!--
			单位为k
		-->
		<property name="spillsFileBufferSize">1k</property>

		<property name="useStreamOutput">0</property>

		<!--
			单位为m
		-->
		<property name="systemReserveMemorySize">384m</property>


		<!--是否采用zookeeper协调切换  -->
		<property name="useZKSwitch">false</property>

		<!-- XA Recovery Log日志路径 -->
		<!--<property name="XARecoveryLogBaseDir">./</property>-->

		<!-- XA Recovery Log日志名称 -->
		<!--<property name="XARecoveryLogBaseName">tmlog</property>-->
		<!--如果为 true的话 严格遵守隔离级别,不会在仅仅只有select语句的时候在事务中切换连接-->
		<property name="strictTxIsolation">false</property>
		<!--如果为0的话,涉及多个DataNode的catlet任务不会跨线程执行-->
		<property name="parallExecute">0</property>
		<property name="serverBacklog">2048</property>
	</system>
	
	<!-- 全局SQL防火墙设置 -->
	<!--白名单可以使用通配符%或着*-->
	<!--例如<host host="127.0.0.*" user="root"/>-->
	<!--例如<host host="127.0.*" user="root"/>-->
	<!--例如<host host="127.*" user="root"/>-->
	<!--例如<host host="1*7.*" user="root"/>-->
	<!--这些配置情况下对于127.0.0.1都能以root账户登录-->
	<!--
	<firewall>
	   <whitehost>
	      <host host="1*7.0.0.*" user="root"/>
	   </whitehost>
       <blacklist check="false">
       </blacklist>
	</firewall>
	-->

	<user name="root" defaultAccount="true">
		<property name="password">123456</property>
		<property name="schemas">testdb</property>
		<property name="defaultSchema">testdb</property>
		<!--No MyCAT Database selected 错误前会尝试使用该schema作为schema，不设置则为null,报错 -->
		
		<!-- 表级 DML 权限设置 -->
		<!-- 		
		<privileges check="false">
			<schema name="TESTDB" dml="0110" >
				<table name="tb01" dml="0000"></table>
				<table name="tb02" dml="1111"></table>
			</schema>
		</privileges>		
		 -->
	</user>

	<user name="user">
		<property name="password">user</property>
		<property name="schemas">testdb</property>
		<property name="readOnly">true</property>
		<property name="defaultSchema">testdb</property>
	</user>

</mycat:server>

c)  /usr/local/mycat/conf/rule.xml

<?xml version="1.0" encoding="UTF-8"?>
<!-- - - Licensed under the Apache License, Version 2.0 (the "License"); 
	- you may not use this file except in compliance with the License. - You 
	may obtain a copy of the License at - - http://www.apache.org/licenses/LICENSE-2.0 
	- - Unless required by applicable law or agreed to in writing, software - 
	distributed under the License is distributed on an "AS IS" BASIS, - WITHOUT 
	WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. - See the 
	License for the specific language governing permissions and - limitations 
	under the License. -->
<!DOCTYPE mycat:rule SYSTEM "rule.dtd">
<mycat:rule xmlns:mycat="http://io.mycat/">
	<tableRule name="rule1">
		<rule>
			<columns>id</columns>
			<algorithm>func1</algorithm>
		</rule>
	</tableRule>

	<tableRule name="sharding-by-date">
		<rule>
			<columns>createTime</columns>
			<algorithm>partbyday</algorithm>
		</rule>
	</tableRule>

	<tableRule name="rule2">
		<rule>
			<columns>user_id</columns>
			<algorithm>func1</algorithm>
		</rule>
	</tableRule>

	<tableRule name="sharding-by-intfile">
		<rule>
			<columns>sharding_id</columns>
			<algorithm>hash-int</algorithm>
		</rule>
	</tableRule>
	<tableRule name="auto-sharding-long">
		<rule>
			<columns>id</columns>
			<algorithm>rang-long</algorithm>
		</rule>
	</tableRule>
	<tableRule name="mod-long">
		<rule>
			<columns>id</columns>
			<algorithm>mod-long</algorithm>
		</rule>
	</tableRule>
	<tableRule name="sharding-by-murmur">
		<rule>
			<columns>id</columns>
			<algorithm>murmur</algorithm>
		</rule>
	</tableRule>
	<tableRule name="crc32slot">
		<rule>
			<columns>id</columns>
			<algorithm>crc32slot</algorithm>
		</rule>
	</tableRule>
	<tableRule name="sharding-by-month">
		<rule>
			<columns>create_time</columns>
			<algorithm>partbymonth</algorithm>
		</rule>
	</tableRule>
	<tableRule name="latest-month-calldate">
		<rule>
			<columns>calldate</columns>
			<algorithm>latestMonth</algorithm>
		</rule>
	</tableRule>

	<tableRule name="auto-sharding-rang-mod">
		<rule>
			<columns>id</columns>
			<algorithm>rang-mod</algorithm>
		</rule>
	</tableRule>

	<tableRule name="jch">
		<rule>
			<columns>id</columns>
			<algorithm>jump-consistent-hash</algorithm>
		</rule>
	</tableRule>

	<function name="murmur"
			  class="io.mycat.route.function.PartitionByMurmurHash">
		<property name="seed">0</property><!-- 默认是0 -->
		<property name="count">3</property><!-- 要分片的数据库节点数量，必须指定，否则没法分片 -->
		<property name="virtualBucketTimes">160</property><!-- 一个实际的数据库节点被映射为这么多虚拟节点，默认是160倍，也就是虚拟节点数是物理节点数的160倍 -->
		<!-- <property name="weightMapFile">weightMapFile</property> 节点的权重，没有指定权重的节点默认是1。以properties文件的格式填写，以从0开始到count-1的整数值也就是节点索引为key，以节点权重值为值。所有权重值必须是正整数，否则以1代替 -->
		<!-- <property name="bucketMapPath">/etc/mycat/bucketMapPath</property>
			用于测试时观察各物理节点与虚拟节点的分布情况，如果指定了这个属性，会把虚拟节点的murmur hash值与物理节点的映射按行输出到这个文件，没有默认值，如果不指定，就不会输出任何东西 -->
	</function>

	<function name="crc32slot"
			  class="io.mycat.route.function.PartitionByCRC32PreSlot">
		<property name="count">2</property><!-- 要分片的数据库节点数量，必须指定，否则没法分片 -->
	</function>
	<function name="hash-int"
			  class="io.mycat.route.function.PartitionByFileMap">
		<property name="mapFile">partition-hash-int.txt</property>
	</function>
	<function name="rang-long"
			  class="io.mycat.route.function.AutoPartitionByLong">
		<property name="mapFile">autopartition-long.txt</property>
	</function>
	<function name="mod-long" class="io.mycat.route.function.PartitionByMod">
		<!-- how many data nodes -->
		<property name="count">3</property>
	</function>

	<function name="func1" class="io.mycat.route.function.PartitionByLong">
		<property name="partitionCount">8</property>
		<property name="partitionLength">128</property>
	</function>
	<function name="latestMonth"
			  class="io.mycat.route.function.LatestMonthPartion">
		<property name="splitOneDay">24</property>
	</function>
	<function name="partbymonth"
			  class="io.mycat.route.function.PartitionByMonth">
		<property name="dateFormat">yyyy-MM-dd</property>
		<property name="sBeginDate">2015-01-01</property>
	</function>


	<function name="partbyday"
			  class="io.mycat.route.function.PartitionByDate">
		<property name="dateFormat">yyyy-MM-dd</property>
		<property name="sNaturalDay">0</property>
		<property name="sBeginDate">2014-01-01</property>
		<property name="sEndDate">2014-01-31</property>
		<property name="sPartionDay">10</property>
	</function>

	<function name="rang-mod" class="io.mycat.route.function.PartitionByRangeMod">
		<property name="mapFile">partition-range-mod.txt</property>
	</function>

	<function name="jump-consistent-hash" class="io.mycat.route.function.PartitionByJumpConsistentHash">
		<property name="totalBuckets">3</property>
	</function>
</mycat:rule>

第三步、建立物理数据库（db1、db2、db3用于分库存储数据）。

1、用navicat建立后如下图：

2、在物理数据库（db1、db2、db3用于分库存储数据）中分别建立表：tb_test

DROP TABLE IF EXISTS `tb_test`;
CREATE TABLE `tb_test` (
  `id` bigint(20) NOT NULL,
  `title` varchar(100) NOT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

 

第四步、启动mycat

1、在/usr/local/mycat/bin下执行

第五步、验证分库分表实现

1、用Navicat连接mycat（mycat服务的监听端口是8066），发现存在

2、发现已存在逻辑数据库testdb（此数据库部署真实存储数据，相当于分库的gateway）和表

 

3、在此逻辑库中执行数据插入语句

INSERT INTO `tb_test` (`id`, `title`) VALUES ('1', '1');
INSERT INTO `tb_test` (`id`, `title`) VALUES ('2', '2');
INSERT INTO `tb_test` (`id`, `title`) VALUES ('3', '3');
INSERT INTO `tb_test` (`id`, `title`) VALUES ('4', '4');
INSERT INTO `tb_test` (`id`, `title`) VALUES ('5', '5');
INSERT INTO `tb_test` (`id`, `title`) VALUES ('6', '6');

4、去物理数据库db1、db2、db3中见证数据：数据分散到各个数据库，写入成功

 

5、通过逻辑库查询三个数据库的全量数据