【Mycat】Mycat核心开发者带你轻松掌握Mycat路由转发！！

写在前面

熟悉Mycat的小伙伴都知道，Mycat一个很重要的功能就是路由转发，那么，这篇文章就带着大家一起来看看Mycat是如何进行路由转发的，好了，不多说了，我们直接进入主题。

环境准备

软件版本

操作系统：CentOS-6.8

JDK版本：jdk1.8

Mycat版本：Mycat-server-1.6

MySQL：5.7

注意：这里，我将Mycat和MySQL安装在同一台虚拟机(IP：192.168.209.140 主机名为:binghe140)，大家也可以将Mycat和MySQL安装到不同的主机上，测试效果是一样的。

创建物理库

mysql -uroot -proot -h192.168.209.140 -P3306

drop database if exists db1;
create database db1;
drop database if exists db2;
create database db2;
drop database if exists db3;
create database db3;

配置Mycat

schema.xml配置

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

	<schema name="binghe" checkSQLschema="false" sqlMaxLimit="100">
		<table name="travelrecord" dataNode="dn1,dn2,dn3" rule="auto-sharding-long"></table>
	</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="native" switchType="1"  slaveThreshold="100">
		<heartbeat>select user()</heartbeat>
		<!-- can have multi write hosts -->
		<writeHost host="hostM1" url="127.0.0.1:3306" user="root" password="root"></writeHost>

		<writeHost host="hostM2" url="127.0.0.1:3306" user="root" password="root"></writeHost>
		<!--<writeHost host="hostS1" url="localhost:3316" user="root"-->
			<!--password="123456" />-->
		<!-- <writeHost host="hostM2" url="localhost:3316" user="root" password="123456"/> -->
	</dataHost>
</mycat:schema>

server.xml配置

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mycat:server SYSTEM "server.dtd">
<mycat:server xmlns:mycat="http://org.opencloudb/">
	<system>
	<property name="defaultSqlParser">druidparser</property>
	</system>
	<user name="binghe">
		<property name="password">binghe.123</property>
		<property name="schemas">binghe</property>
	</user>
	<user name="test">
		<property name="password">test</property>
		<property name="schemas">binghe</property>
		<property name="readOnly">true</property>
	</user>
</mycat:server>

rule.xml配置

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mycat:rule SYSTEM "rule.dtd">
<mycat:rule xmlns:mycat="http://org.opencloudb/">
	<tableRule name="rule1">
		<rule>
			<columns>id</columns>
			<algorithm>func1</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="sharding-by-month">
		<rule>
			<columns>create_date</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="org.opencloudb.route.function.PartitionByMurmurHash">
		<property name="seed">0</property>
		<property name="count">2</property>
		<property name="virtualBucketTimes">160</property>
	</function>
	<function name="hash-int"
		class="org.opencloudb.route.function.PartitionByFileMap">
		<property name="mapFile">partition-hash-int.txt</property>
	</function>
	<function name="rang-long"
		class="org.opencloudb.route.function.AutoPartitionByLong">
		<property name="mapFile">autopartition-long.txt</property>
	</function>
	<function name="mod-long" class="org.opencloudb.route.function.PartitionByMod">
		<!-- how many data nodes -->
		<property name="count">3</property>
	</function>

	<function name="func1" class="org.opencloudb.route.function.PartitionByLong">
		<property name="partitionCount">8</property>
		<property name="partitionLength">128</property>
	</function>
	<function name="latestMonth"
		class="org.opencloudb.route.function.LatestMonthPartion">
		<property name="splitOneDay">24</property>
	</function>
	<function name="partbymonth"
		class="org.opencloudb.route.function.PartitionByMonth">
		<property name="dateFormat">yyyy-MM-dd</property>
		<property name="sBeginDate">2020-01-01</property>
	</function>

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

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

登录Mycat

登录Mycat

命令行输入以下命令登录Mycat

D:\>mysql -ubinghe -pbinghe.123 -h192.168.209.140 -P8066
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 2
Server version: 5.5.8-mycat-1.6.1-RELEASE-20170807215126 MyCat Server (OpenCloundDB)

Copyright (c) 2000, 2016, Oracle and/or its affiliates. All rights reserved.

Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

mysql>

创建表测试

输入以下命令查看创建表的路由

create table travelrecord (id bigint not null primary key,user_id varchar(100),traveldate DATE, fee decimal,days int);

结果如下：

mysql> explain create table travelrecord (id bigint not null primary key,user_id varchar(100),traveldate DATE, fee decimal,days int);
+-----------+-----------------------------------------------------------------------------------------------------------------------+
| DATA_NODE | SQL                                                                                                                   |
+-----------+-----------------------------------------------------------------------------------------------------------------------+
| dn1       | create table travelrecord (id bigint not null primary key,user_id varchar(100),traveldate DATE, fee decimal,days int) |
| dn2       | create table travelrecord (id bigint not null primary key,user_id varchar(100),traveldate DATE, fee decimal,days int) |
| dn3       | create table travelrecord (id bigint not null primary key,user_id varchar(100),traveldate DATE, fee decimal,days int) |
+-----------+-----------------------------------------------------------------------------------------------------------------------+
3 rows in set (0.00 sec)

mysql>

说明创建表的SQL语句被Mycat路由到dn1,dn2,dn3三个节点上，也就是说在3个节点上都执行了创建表的SQL。

我们输入建表语句：

mysql> create table travelrecord (id bigint not null primary key,user_id varchar(100),traveldate DATE, fee decimal,days int);
Query OK, 0 rows affected (0.18 sec)

此时，将会在dn1,dn2,dn3三个节点上创建travelrecord表。

录入数据测试

录入到dn1节点

我们在命令行输入如下SQL语句

explain insert into travelrecord (id,user_id,traveldate,fee,days) values(100001,'binghe','2020-11-10',510.5,3);

结果如下：

mysql> explain insert into travelrecord (id,user_id,traveldate,fee,days) values(100001,'binghe','2020-11-10',510.5,3);
+-----------+-------------------------------------------------------------------------------------------------------------+
| DATA_NODE | SQL                                                                                                         |
+-----------+-------------------------------------------------------------------------------------------------------------+
| dn1       | insert into travelrecord (id,user_id,traveldate,fee,days) values(100001,'binghe','2020-11-10',510.5,3) |
+-----------+-------------------------------------------------------------------------------------------------------------+
1 row in set (0.00 sec)

说明Mycat将SQL路由到了dn1节点。

我们执行插入语句：

mysql> insert into travelrecord (id,user_id,traveldate,fee,days) values(100001,'binghe','2020-11-10',510.5,3);
Query OK, 1 row affected, 1 warning (0.01 sec)

mysql>

录入到dn2节点

我们在命令行输入如下语句：

explain insert into travelrecord (id,user_id,traveldate,fee,days) values(8000004,'binghe','2020-11-10',510.5,3);

结果如下：

mysql> explain insert into travelrecord (id,user_id,traveldate,fee,days) values(8000004,'binghe','2020-11-10',510.5,3);
+-----------+--------------------------------------------------------------------------------------------------------------+
| DATA_NODE | SQL                                                                                                          |
+-----------+--------------------------------------------------------------------------------------------------------------+
| dn2       | insert into travelrecord (id,user_id,traveldate,fee,days) values(8000004,'binghe','2020-11-10',510.5,3) |
+-----------+--------------------------------------------------------------------------------------------------------------+
1 row in set (0.00 sec)

说明Mycat将SQL路由到了dn2节点，我们执行插入语句：

mysql> insert into travelrecord (id,user_id,traveldate,fee,days) values(8000004,'binghe','2020-11-10',510.5,3);
Query OK, 1 row affected, 1 warning (0.06 sec)

路由到dn3节点

我们在命令行输入如下语句

explain insert into travelrecord (id,user_id,traveldate,fee,days) values(10000004,'binghe','2020-11-10',510.5,3);

结果为：

mysql> explain insert into travelrecord (id,user_id,traveldate,fee,days) values(10000004,'binghe','2020-11-10',510.5,3);
+-----------+---------------------------------------------------------------------------------------------------------------+
| DATA_NODE | SQL                                                                                                           |
+-----------+---------------------------------------------------------------------------------------------------------------+
| dn3       | insert into travelrecord (id,user_id,traveldate,fee,days) values(10000004,'binghe','2020-11-10',510.5,3) |
+-----------+---------------------------------------------------------------------------------------------------------------+
1 row in set (0.00 sec)

说明Mycat将SQL路由到了dn3节点，我们同样执行插入语句的操作

mysql>  insert into travelrecord (id,user_id,traveldate,fee,days) values(10000004,'binghe','2020-11-10',510.5,3);
Query OK, 1 row affected, 1 warning (0.01 sec)

查询测试

查询所有数据

在命令行执行如下语句：

explain select * from travelrecord;

结果为：

mysql> explain select * from travelrecord;
+-----------+--------------------------------------+
| DATA_NODE | SQL                                  |
+-----------+--------------------------------------+
| dn1       | SELECT * FROM travelrecord LIMIT 100 |
| dn2       | SELECT * FROM travelrecord LIMIT 100 |
| dn3       | SELECT * FROM travelrecord LIMIT 100 |
+-----------+--------------------------------------+
3 rows in set (0.01 sec)

说明查询所有的数据，Mycat是将SQL语句路由到了所有的数据分片，即dn1,dn2,dn3节点上。

根据id查询指定数据

我们分别在命令行中执行如下SQL:

explain select * from travelrecord where id = 1000004;
explain select * from travelrecord where id = 8000004;
explain select * from travelrecord where id = 10000004;

得到的结果依次如下：

mysql> explain select * from travelrecord where id = 1000004;
+-----------+---------------------------------------------------------+
| DATA_NODE | SQL                                                     |
+-----------+---------------------------------------------------------+
| dn1       | SELECT * FROM travelrecord WHERE id = 1000004 LIMIT 100 |
+-----------+---------------------------------------------------------+
1 row in set (0.06 sec)

mysql> explain select * from travelrecord where id = 8000004;
+-----------+---------------------------------------------------------+
| DATA_NODE | SQL                                                     |
+-----------+---------------------------------------------------------+
| dn2       | SELECT * FROM travelrecord WHERE id = 8000004 LIMIT 100 |
+-----------+---------------------------------------------------------+
1 row in set (0.00 sec)

mysql> explain select * from travelrecord where id = 10000004;
+-----------+----------------------------------------------------------+
| DATA_NODE | SQL                                                      |
+-----------+----------------------------------------------------------+
| dn3       | SELECT * FROM travelrecord WHERE id = 10000004 LIMIT 100 |
+-----------+----------------------------------------------------------+
1 row in set (0.00 sec)

说明：按照分片字段查询，Mycat只会将SQL路由到指定的数据分片。

删表测试

在命令行输入如下SQL：

explain drop table travelrecord;

结果如下

mysql> explain drop table travelrecord;
+-----------+-------------------------+
| DATA_NODE | SQL                     |
+-----------+-------------------------+
| dn1       | drop table travelrecord |
| dn2       | drop table travelrecord |
| dn3       | drop table travelrecord |
+-----------+-------------------------+
3 rows in set (0.00 sec)

有结果可知，删表操作和创建表操作一样，Mycat在本实例中都会将SQL路由到所有的数据分片。

注意：本文的Mycat路由结果针对本文的配置实例，其他配置下，Mycat的路由结果可能会有不同。

好了，我们今天就到这儿吧，我是冰河，我们下期见~~

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