本篇内容介绍了“MyCat怎么实现分库分表”的有关知识，在实际案例的操作过程中，不少人都会遇到这样的困境，接下来就让小编带领大家学习一下如何处理这些情况吧！希望大家仔细阅读，能够学有所成！
项目环境：
192.168.8.30 mycat
192.168.8.31 node1
192.168.8.32 node2
192.168.8.33 node3
三个节点MySQL均为单实例
一、创建测试库
node1
create database testdb01;create database testdb02;create database testdb03;node2
create database testdb13;create database testdb14;create database testdb15;node3
create database testdb25;create database testdb26;create database testdb27;二、配置schema.xml
<?xml version="1.0"?><!DOCTYPE mycat:schema SYSTEM "schema.dtd"><mycat:schema xmlns:mycat="http://io.mycat/"> <schema name="mycatdb" checkSQLschema="false" sqlMaxLimit="100"> <table name="user04" dataNode="dn$1-3,dn$13-15,dn$25-27" rule="sharding-by-murmur-user04-id"></table> </schema><!-- <dataNode name="dn1$0-743" dataHost="localhost1" database="db$0-743"/> --> <dataNode name="dn1" dataHost="node1" database="testdb01" /> <dataNode name="dn2" dataHost="node1" database="testdb02" /> <dataNode name="dn3" dataHost="node1" database="testdb03" /> <dataNode name="dn13" dataHost="node2" database="testdb13" /> <dataNode name="dn14" dataHost="node2" database="testdb14" /> <dataNode name="dn15" dataHost="node2" database="testdb15" /> <dataNode name="dn25" dataHost="node3" database="testdb25" /> <dataNode name="dn26" dataHost="node3" database="testdb26" /> <dataNode name="dn27" dataHost="node3" database="testdb27" /> <!--<dataNode name="dn4" dataHost="sequoiadb1" database="SAMPLE" /> <dataNode name="jdbc_dn1" dataHost="jdbchost" database="db1" /><dataNodename="jdbc_dn2" dataHost="jdbchost" database="db2" /><dataNode name="jdbc_dn3" dataHost="jdbchost" database="db3" /> --><dataHost name="node1" maxCon="1000" minCon="10" balance="1" writeType="0" dbType="mysql" dbDriver="native" switchType="1" slaveThreshold="100"> <heartbeat>select user()</heartbeat> <!-- can have multi write hosts --> <writeHost host="192.168.8.31" url="192.168.8.31:3306" user="root" password="mysql"></writeHost> </dataHost> <dataHost name="node2" maxCon="1000" minCon="10" balance="1" writeType="0" dbType="mysql" dbDriver="native" switchType="1" slaveThreshold="100"> <heartbeat>select user()</heartbeat> <!-- can have multi write hosts --> <writeHost host="192.168.8.32" url="192.168.8.32:3306" user="root" password="mysql"></writeHost> </dataHost> <dataHost name="node3" maxCon="1000" minCon="10" balance="1" writeType="0" dbType="mysql" dbDriver="native" switchType="1" slaveThreshold="100"> <heartbeat>select user()</heartbeat> <!-- can have multi write hosts --> <writeHost host="192.168.8.33" url="192.168.8.33:3306" user="root" password="mysql"></writeHost> </dataHost></mycat:schema>三、配置rule.xml
<tableRule name="sharding-by-murmur-user04-id"> <rule> <columns>id</columns> <algorithm>murmur-id</algorithm> </rule></tableRule><function name="murmur-id" class="io.mycat.route.function.PartitionByMurmurHash"> <property name="seed">0</property><!-- 默认是 0 --> <property name="type">0</property><!-- 默认是 0, 表示 integer,非 0 表示 string--> <property name="count">9</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 --> </function>四、配置server.xml
<user name="root" defaultAccount="true"><property name="password">mysql</property><property name="schemas">mycatdb</property></user>五、启动mycat
/usr/local/mycat/bin/mycat start查看mycat日志
STATUS | wrapper | 2018/11/22 16:48:27 | --> Wrapper Started as DaemonSTATUS | wrapper | 2018/11/22 16:48:27 | Launching a JVM...INFO | jvm 1 | 2018/11/22 16:48:27 | OpenJDK 64-Bit Server VM warning: ignoring option MaxPermSize=64M; support was removed in 8.0INFO | jvm 1 | 2018/11/22 16:48:29 | Wrapper (Version 3.2.3) http://wrapper.tanukisoftware.orgINFO | jvm 1 | 2018/11/22 16:48:29 | Copyright 1999-2006 Tanuki Software, Inc. All Rights Reserved.INFO | jvm 1 | 2018/11/22 16:48:29 | INFO | jvm 1 | 2018/11/22 16:48:34 | MyCAT Server startup successfully. see logs in logs/mycat.log六、登录MySQL查看逻辑表
mysql -uroot -pmysql -P8066 -h292.168.8.30mysql> show databases;+----------+| DATABASE |+----------+| mycatdb |+----------+1 row in set (0.00 sec)mysql> use mycatdb;Reading table information for completion of table and column namesYou can turn off this feature to get a quicker startup with -ADatabase changedmysql> show tables;+-------------------+| Tables in mycatdb |+-------------------+| order01 || orderdetail01 || user01 || user02 || user03 || user04 |+-------------------+6 rows in set (0.01 sec)mysql> select * from user04;ERROR 1105 (HY000): Table 'testdb03.user04' doesn't existmysql> drop table if exists user04;Query OK, 0 rows affected, 1 warning (0.15 sec)mysql> create table user04 ( -> id int not null auto_increment, -> name varchar(64), -> primary key (id) -> );Query OK, 0 rows affected (0.61 sec)七、插入测试数据
insert into user04(id,name) values(1,'steven');insert into user04(id,name) values(2,'steven');insert into user04(id,name) values(3,'steven');insert into user04(id,name) values(4,'steven');insert into user04(id,name) values(5,'steven');insert into user04(id,name) values(6,'steven');insert into user04(id,name) values(7,'steven');insert into user04(id,name) values(8,'steven');insert into user04(id,name) values(9,'steven');insert into user04(id,name) values(10,'steven');insert into user04(id,name) values(11,'steven');insert into user04(id,name) values(12,'steven');insert into user04(id,name) values(13,'steven');insert into user04(id,name) values(14,'steven');insert into user04(id,name) values(15,'steven');insert into user04(id,name) values(16,'steven');insert into user04(id,name) values(17,'steven');insert into user04(id,name) values(18,'steven');insert into user04(id,name) values(19,'steven');insert into user04(id,name) values(20,'steven');insert into user04(id,name) values(21,'steven');insert into user04(id,name) values(22,'steven');insert into user04(id,name) values(23,'steven');insert into user04(id,name) values(24,'steven');insert into user04(id,name) values(25,'steven');insert into user04(id,name) values(26,'steven');insert into user04(id,name) values(27,'steven');insert into user04(id,name) values(28,'steven');insert into user04(id,name) values(29,'steven');insert into user04(id,name) values(30,'steven');insert into user04(id,name) values(31,'steven');insert into user04(id,name) values(32,'steven');insert into user04(id,name) values(33,'steven');insert into user04(id,name) values(34,'steven');insert into user04(id,name) values(35,'steven');insert into user04(id,name) values(36,'steven');insert into user04(id,name) values(37,'steven');insert into user04(id,name) values(38,'steven');insert into user04(id,name) values(39,'steven');insert into user04(id,name) values(40,'steven');insert into user04(id,name) values(41,'steven');insert into user04(id,name) values(42,'steven');insert into user04(id,name) values(43,'steven');insert into user04(id,name) values(44,'steven');insert into user04(id,name) values(45,'steven');insert into user04(id,name) values(46,'steven');insert into user04(id,name) values(47,'steven');insert into user04(id,name) values(48,'steven');insert into user04(id,name) values(49,'steven');insert into user04(id,name) values(50,'steven');八、验证数据
三个node只在testdb01-03,testdb13-15，testdb25-27，所以除了这9个物理库之外，其他库查不到分片。
下面在三个node分别验证出分片信息：
node1
mysql> select * from testdb01.user04;+----+--------+| id | name |+----+--------+| 8 | steven || 14 | steven || 16 | steven || 17 | steven || 34 | steven || 49 | steven |+----+--------+6 rows in set (0.00 sec)mysql> select * from testdb02.user04;+----+--------+| id | name |+----+--------+| 9 | steven || 10 | steven || 44 | steven || 45 | steven || 46 | steven || 48 | steven |+----+--------+6 rows in set (0.00 sec)mysql> select * from testdb03.user04;+----+--------+| id | name |+----+--------+| 11 | steven || 24 | steven || 33 | steven || 35 | steven || 40 | steven |+----+--------+5 rows in set (0.00 sec)node2
mysql> select * from testdb13.user04;+----+--------+| id | name |+----+--------+| 20 | steven || 25 | steven || 38 | steven || 39 | steven |+----+--------+4 rows in set (0.00 sec)mysql> select * from testdb14.user04;+----+--------+| id | name |+----+--------+| 1 | steven || 41 | steven || 50 | steven |+----+--------+3 rows in set (0.01 sec)mysql> select * from testdb15.user04;+----+--------+| id | name |+----+--------+| 12 | steven || 18 | steven || 32 | steven || 36 | steven |+----+--------+4 rows in set (0.00 sec)node3
mysql> select * from testdb25.user04;+----+--------+| id | name |+----+--------+| 6 | steven || 13 | steven || 19 | steven || 23 | steven || 27 | steven || 28 | steven || 29 | steven || 31 | steven || 37 | steven |+----+--------+9 rows in set (0.00 sec)mysql> select * from testdb26.user04;+----+--------+| id | name |+----+--------+| 4 | steven || 5 | steven || 15 | steven || 22 | steven || 42 | steven |+----+--------+5 rows in set (0.00 sec)mysql> select * from testdb27.user04;+----+--------+| id | name |+----+--------+| 2 | steven || 3 | steven || 7 | steven || 21 | steven || 26 | steven || 30 | steven || 43 | steven || 47 | steven |+----+--------+8 rows in set (0.00 sec)“MyCat怎么实现分库分表”的内容就介绍到这里了，感谢大家的阅读。如果想了解更多行业相关的知识可以关注编程网网站，小编将为大家输出更多高质量的实用文章！
