这篇文章主要介绍“MyCat分库分表中怎么实现ER分片”，在日常操作中，相信很多人在MyCat分库分表中怎么实现ER分片问题上存在疑惑，小编查阅了各式资料，整理出简单好用的操作方法，希望对大家解答”MyCat分库分表中怎么实现ER分片”的疑惑有所帮助！接下来，请跟着小编一起来学习吧！
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、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="order01" dataNode="dn$1-3,dn$13-15,dn$25-27" rule="mod-long"> <childTable name="orderdetail01" primaryKey="orderdetail_id" joinKey="order_id" parentKey="order_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="dn4" dataHost="node1" database="testdb04" /> <dataNode name="dn5" dataHost="node1" database="testdb05" /> <dataNode name="dn6" dataHost="node1" database="testdb06" /> <dataNode name="dn7" dataHost="node1" database="testdb07" /> <dataNode name="dn8" dataHost="node1" database="testdb08" /> <dataNode name="dn9" dataHost="node1" database="testdb09" /> <dataNode name="dn10" dataHost="node1" database="testdb10" /> <dataNode name="dn11" dataHost="node1" database="testdb11" /> <dataNode name="dn12" dataHost="node1" database="testdb12" /> <dataNode name="dn13" dataHost="node2" database="testdb13" /> <dataNode name="dn14" dataHost="node2" database="testdb14" /> <dataNode name="dn15" dataHost="node2" database="testdb15" /> <dataNode name="dn16" dataHost="node2" database="testdb16" /> <dataNode name="dn17" dataHost="node2" database="testdb17" /> <dataNode name="dn18" dataHost="node2" database="testdb18" /> <dataNode name="dn19" dataHost="node2" database="testdb19" /> <dataNode name="dn20" dataHost="node2" database="testdb20" /> <dataNode name="dn21" dataHost="node2" database="testdb21" /> <dataNode name="dn22" dataHost="node2" database="testdb22" /> <dataNode name="dn23" dataHost="node2" database="testdb23" /> <dataNode name="dn24" dataHost="node2" database="testdb24" /> <dataNode name="dn25" dataHost="node3" database="testdb25" /> <dataNode name="dn26" dataHost="node3" database="testdb26" /> <dataNode name="dn27" dataHost="node3" database="testdb27" /> <dataNode name="dn28" dataHost="node3" database="testdb28" /> <dataNode name="dn29" dataHost="node3" database="testdb29" /> <dataNode name="dn30" dataHost="node3" database="testdb30" /> <dataNode name="dn31" dataHost="node3" database="testdb31" /> <dataNode name="dn32" dataHost="node3" database="testdb32" /> <dataNode name="dn33" dataHost="node3" database="testdb33" /> <dataNode name="dn34" dataHost="node3" database="testdb34" /> <dataNode name="dn35" dataHost="node3" database="testdb35" /> <!--<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>二、配置rule.xml
<mycat:rule xmlns:mycat="http://io.mycat/"> <tableRule name="mod-long"> <rule> <columns>order_id</columns> <algorithm>mod-long</algorithm> </rule> </tableRule> <function name="mod-long" class="io.mycat.route.function.PartitionByMod"> <property name="count">9</property> </function> </mycat:rule>三、配置server.xml
<user name="root" defaultAccount="true"><property name="password">mysql</property><property name="schemas">mycatdb</property></user>四、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;五、启动mycat
/usr/local/mycat/bin/mycat start查看mycat日志
STATUS | wrapper | 2018/11/22 14:12:55 | --> Wrapper Started as DaemonSTATUS | wrapper | 2018/11/22 14:12:55 | Launching a JVM...INFO | jvm 1 | 2018/11/22 14:12:55 | OpenJDK 64-Bit Server VM warning: ignoring option MaxPermSize=64M; support was removed in 8.0INFO | jvm 1 | 2018/11/22 14:12:58 | Wrapper (Version 3.2.3) http://wrapper.tanukisoftware.orgINFO | jvm 1 | 2018/11/22 14:12:58 | Copyright 1999-2006 Tanuki Software, Inc. All Rights Reserved.INFO | jvm 1 | 2018/11/22 14:12:58 | INFO | jvm 1 | 2018/11/22 14:13:04 | 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 (0.02 sec)mysql> use mycatdbReading 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 |+-------------------+4 rows in set (0.00 sec)mysql> select * from order01;ERROR 1105 (HY000): Table 'testdb03.order01' doesn't existmysql> mysql> drop table if exists order01;Query OK, 0 rows affected, 1 warning (0.46 sec)mysql> drop table if exists orderdetail01;Query OK, 0 rows affected, 1 warning (0.16 sec)mysql> CREATE TABLE order01( -> order_id INT NOT NULL AUTO_INCREMENT PRIMARY KEY, -> number VARCHAR(64), -> createtime DATETIME);Query OK, 0 rows affected (0.58 sec)mysql> CREATE TABLE orderdetail01( -> orderdetail_id INT AUTO_INCREMENT PRIMARY KEY, -> order_id INT, -> order_status CHAR(1), -> addresss VARCHAR(128), -> createtime DATETIME, -> CONSTRAINT fk_iorder01 FOREIGN KEY (order_id) REFERENCES order01 -> (order_id));Query OK, 0 rows affected (0.63 sec)七、插入测试数据
父表和子表各插入9条记录
INSERT INTO order01(order_id,number,createtime) VALUES(1,'steven101',NOW());INSERT INTO orderdetail01(orderdetail_id,order_id,order_status,addresss,createtime) VALUES (1,1,'1','steven101(ID=1,steven101)',NOW());INSERT INTO order01(order_id,number,createtime) VALUES(2,'steven201',NOW());INSERT INTO orderdetail01(orderdetail_id,order_id,order_status,addresss,createtime) VALUES (2,2,'1','steven201(ID=2,steven201)',NOW());INSERT INTO order01(order_id,number,createtime) VALUES(3,'steven301',NOW());INSERT INTO orderdetail01(orderdetail_id,order_id,order_status,addresss,createtime) VALUES (3,3,'1','steven301(ID=3,steven301)',NOW());INSERT INTO order01(order_id,number,createtime) VALUES(4,'steven401',NOW());INSERT INTO orderdetail01(orderdetail_id,order_id,order_status,addresss,createtime) VALUES (4,4,'1','steven401(ID=4,steven401)',NOW());INSERT INTO order01(order_id,number,createtime) VALUES(5,'steven501',NOW());INSERT INTO orderdetail01(orderdetail_id,order_id,order_status,addresss,createtime) VALUES (5,5,'1','steven501(ID=5,steven501)',NOW());INSERT INTO order01(order_id,number,createtime) VALUES(6,'steven601',NOW());INSERT INTO orderdetail01(orderdetail_id,order_id,order_status,addresss,createtime) VALUES (6,6,'1','steven601(ID=6,steven601)',NOW());INSERT INTO order01(order_id,number,createtime) VALUES(7,'steven701',NOW());INSERT INTO orderdetail01(orderdetail_id,order_id,order_status,addresss,createtime) VALUES (7,7,'1','steven701(ID=7,steven701)',NOW());INSERT INTO order01(order_id,number,createtime) VALUES(8,'steven801',NOW());INSERT INTO orderdetail01(orderdetail_id,order_id,order_status,addresss,createtime) VALUES (8,8,'1','steven801(ID=8,steven801)',NOW());INSERT INTO order01(order_id,number,createtime) VALUES(9,'steven901',NOW());INSERT INTO orderdetail01(orderdetail_id,order_id,order_status,addresss,createtime) VALUES (9,9,'1','steven901(ID=9,steven901)',NOW());八、验证数据
schema.xml中，order01和orderdetail01分片只配置了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.order01;+----------+-----------+---------------------+| order_id | number | createtime |+----------+-----------+---------------------+| 9 | steven901 | 2018-11-22 14:21:20 |+----------+-----------+---------------------+1 row in set (0.00 sec)mysql> select * from testdb01.orderdetail01;+----------------+----------+--------------+---------------------------+---------------------+| orderdetail_id | order_id | order_status | addresss | createtime |+----------------+----------+--------------+---------------------------+---------------------+| 9 | 9 | 1 | steven901(ID=9,steven901) | 2018-11-22 14:21:23 |+----------------+----------+--------------+---------------------------+---------------------+1 row in set (0.01 sec)mysql> select * from testdb02.order01;+----------+-----------+---------------------+| order_id | number | createtime |+----------+-----------+---------------------+| 1 | steven101 | 2018-11-22 14:21:18 |+----------+-----------+---------------------+1 row in set (0.00 sec)mysql> select * from testdb02.orderdetail01;+----------------+----------+--------------+---------------------------+---------------------+| orderdetail_id | order_id | order_status | addresss | createtime |+----------------+----------+--------------+---------------------------+---------------------+| 1 | 1 | 1 | steven101(ID=1,steven101) | 2018-11-22 14:21:18 |+----------------+----------+--------------+---------------------------+---------------------+1 row in set (0.01 sec)mysql> select * from testdb03.order01;+----------+-----------+---------------------+| order_id | number | createtime |+----------+-----------+---------------------+| 2 | steven201 | 2018-11-22 14:21:18 |+----------+-----------+---------------------+1 row in set (0.00 sec)mysql> select * from testdb03.orderdetail01;+----------------+----------+--------------+---------------------------+---------------------+| orderdetail_id | order_id | order_status | addresss | createtime |+----------------+----------+--------------+---------------------------+---------------------+| 2 | 2 | 1 | steven201(ID=2,steven201) | 2018-11-22 14:21:18 |+----------------+----------+--------------+---------------------------+---------------------+1 row in set (0.00 sec)node2
mysql> select * from testdb13.order01;+----------+-----------+---------------------+| order_id | number | createtime |+----------+-----------+---------------------+| 3 | steven301 | 2018-11-22 14:21:17 |+----------+-----------+---------------------+1 row in set (0.00 sec)mysql> select * from testdb13.orderdetail01;+----------------+----------+--------------+---------------------------+---------------------+| orderdetail_id | order_id | order_status | addresss | createtime |+----------------+----------+--------------+---------------------------+---------------------+| 3 | 3 | 1 | steven301(ID=3,steven301) | 2018-11-22 14:21:17 |+----------------+----------+--------------+---------------------------+---------------------+1 row in set (0.01 sec)mysql> select * from testdb14.order01;+----------+-----------+---------------------+| order_id | number | createtime |+----------+-----------+---------------------+| 4 | steven401 | 2018-11-22 14:21:17 |+----------+-----------+---------------------+1 row in set (0.00 sec)mysql> select * from testdb14.orderdetail01;+----------------+----------+--------------+---------------------------+---------------------+| orderdetail_id | order_id | order_status | addresss | createtime |+----------------+----------+--------------+---------------------------+---------------------+| 4 | 4 | 1 | steven401(ID=4,steven401) | 2018-11-22 14:21:17 |+----------------+----------+--------------+---------------------------+---------------------+1 row in set (0.00 sec)mysql> select * from testdb15.order01;+----------+-----------+---------------------+| order_id | number | createtime |+----------+-----------+---------------------+| 5 | steven501 | 2018-11-22 14:21:18 |+----------+-----------+---------------------+1 row in set (0.00 sec)mysql> select * from testdb15.orderdetail01;+----------------+----------+--------------+---------------------------+---------------------+| orderdetail_id | order_id | order_status | addresss | createtime |+----------------+----------+--------------+---------------------------+---------------------+| 5 | 5 | 1 | steven501(ID=5,steven501) | 2018-11-22 14:21:18 |+----------------+----------+--------------+---------------------------+---------------------+1 row in set (0.00 sec)node3
mysql> select * from testdb25.order01;+----------+-----------+---------------------+| order_id | number | createtime |+----------+-----------+---------------------+| 6 | steven601 | 2018-11-22 14:21:20 |+----------+-----------+---------------------+1 row in set (0.00 sec)mysql> select * from testdb25.orderdetail01;+----------------+----------+--------------+---------------------------+---------------------+| orderdetail_id | order_id | order_status | addresss | createtime |+----------------+----------+--------------+---------------------------+---------------------+| 6 | 6 | 1 | steven601(ID=6,steven601) | 2018-11-22 14:21:20 |+----------------+----------+--------------+---------------------------+---------------------+1 row in set (0.00 sec)mysql> select * from testdb26.order01;+----------+-----------+---------------------+| order_id | number | createtime |+----------+-----------+---------------------+| 7 | steven701 | 2018-11-22 14:21:20 |+----------+-----------+---------------------+1 row in set (0.00 sec)mysql> select * from testdb26.orderdetail01;+----------------+----------+--------------+---------------------------+---------------------+| orderdetail_id | order_id | order_status | addresss | createtime |+----------------+----------+--------------+---------------------------+---------------------+| 7 | 7 | 1 | steven701(ID=7,steven701) | 2018-11-22 14:21:20 |+----------------+----------+--------------+---------------------------+---------------------+1 row in set (0.00 sec)mysql> select * from testdb27.order01;+----------+-----------+---------------------+| order_id | number | createtime |+----------+-----------+---------------------+| 8 | steven801 | 2018-11-22 14:21:20 |+----------+-----------+---------------------+1 row in set (0.01 sec)mysql> select * from testdb27.orderdetail01;+----------------+----------+--------------+---------------------------+---------------------+| orderdetail_id | order_id | order_status | addresss | createtime |+----------------+----------+--------------+---------------------------+---------------------+| 8 | 8 | 1 | steven801(ID=8,steven801) | 2018-11-22 14:21:20 |+----------------+----------+--------------+---------------------------+---------------------+1 row in set (0.00 sec)到此，关于“MyCat分库分表中怎么实现ER分片”的学习就结束了，希望能够解决大家的疑惑。理论与实践的搭配能更好的帮助大家学习，快去试试吧！若想继续学习更多相关知识，请继续关注编程网网站，小编会继续努力为大家带来更多实用的文章！
