【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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