1. MyCAT基础架构图
image2. MyCAT基础架构准备
2.1 环境准备:
两台虚拟机 db01 db02
每台创建四个mysql实例:3307 3308 3309 3310
2.2 删除历史环境:
pkill mysqld
rm -rf /data/330*
mv /etc/my.cnf /etc/my.cnf.bak
2.3 创建相关目录初始化数据
mkdir /data/33{07..10}/data -p
mysqld --initialize-insecure --user=mysql --datadir=/data/3307/data --basedir=/application/mysql
mysqld --initialize-insecure --user=mysql --datadir=/data/3308/data --basedir=/application/mysql
mysqld --initialize-insecure --user=mysql --datadir=/data/3309/data --basedir=/application/mysql
mysqld --initialize-insecure --user=mysql --datadir=/data/3310/data --basedir=/application/mysql
2.4 准备配置文件和启动脚本
========db01==============
cat >/data/3307/my.cnf<<EOF
[mysqld]
basedir=/application/mysql
datadir=/data/3307/data
socket=/data/3307/mysql.sock
port=3307
log-error=/data/3307/mysql.log
log_bin=/data/3307/mysql-bin
binlog_format=row
skip-name-resolve
server-id=7
gtid-mode=on
enforce-gtid-consistency=true
log-slave-updates=1
EOF
cat >/data/3308/my.cnf<<EOF
[mysqld]
basedir=/application/mysql
datadir=/data/3308/data
port=3308
socket=/data/3308/mysql.sock
log-error=/data/3308/mysql.log
log_bin=/data/3308/mysql-bin
binlog_format=row
skip-name-resolve
server-id=8
gtid-mode=on
enforce-gtid-consistency=true
log-slave-updates=1
EOF
cat >/data/3309/my.cnf<<EOF
[mysqld]
basedir=/application/mysql
datadir=/data/3309/data
socket=/data/3309/mysql.sock
port=3309
log-error=/data/3309/mysql.log
log_bin=/data/3309/mysql-bin
binlog_format=row
skip-name-resolve
server-id=9
gtid-mode=on
enforce-gtid-consistency=true
log-slave-updates=1
EOF
cat >/data/3310/my.cnf<<EOF
[mysqld]
basedir=/application/mysql
datadir=/data/3310/data
socket=/data/3310/mysql.sock
port=3310
log-error=/data/3310/mysql.log
log_bin=/data/3310/mysql-bin
binlog_format=row
skip-name-resolve
server-id=10
gtid-mode=on
enforce-gtid-consistency=true
log-slave-updates=1
EOF
cat >/etc/systemd/system/mysqld3307.service<<EOF
[Unit]
Description=MySQL Server
Documentation=man:mysqld(8)
Documentation=http://dev.mysql.com/doc/refman/en/using-systemd.html
After=network.target
After=syslog.target
[Install]
WantedBy=multi-user.target
[Service]
User=mysql
Group=mysql
ExecStart=/application/mysql/bin/mysqld --defaults-file=/data/3307/my.cnf
LimitNOFILE = 5000
EOF
cat >/etc/systemd/system/mysqld3308.service<<EOF
[Unit]
Description=MySQL Server
Documentation=man:mysqld(8)
Documentation=http://dev.mysql.com/doc/refman/en/using-systemd.html
After=network.target
After=syslog.target
[Install]
WantedBy=multi-user.target
[Service]
User=mysql
Group=mysql
ExecStart=/application/mysql/bin/mysqld --defaults-file=/data/3308/my.cnf
LimitNOFILE = 5000
EOF
cat >/etc/systemd/system/mysqld3309.service<<EOF
[Unit]
Description=MySQL Server
Documentation=man:mysqld(8)
Documentation=http://dev.mysql.com/doc/refman/en/using-systemd.html
After=network.target
After=syslog.target
[Install]
WantedBy=multi-user.target
[Service]
User=mysql
Group=mysql
ExecStart=/application/mysql/bin/mysqld --defaults-file=/data/3309/my.cnf
LimitNOFILE = 5000
EOF
cat >/etc/systemd/system/mysqld3310.service<<EOF
[Unit]
Description=MySQL Server
Documentation=man:mysqld(8)
Documentation=http://dev.mysql.com/doc/refman/en/using-systemd.html
After=network.target
After=syslog.target
[Install]
WantedBy=multi-user.target
[Service]
User=mysql
Group=mysql
ExecStart=/application/mysql/bin/mysqld --defaults-file=/data/3310/my.cnf
LimitNOFILE = 5000
EOF
========db02===============
cat >/data/3307/my.cnf<<EOF
[mysqld]
basedir=/application/mysql
datadir=/data/3307/data
socket=/data/3307/mysql.sock
port=3307
log-error=/data/3307/mysql.log
log_bin=/data/3307/mysql-bin
binlog_format=row
skip-name-resolve
server-id=17
gtid-mode=on
enforce-gtid-consistency=true
log-slave-updates=1
EOF
cat >/data/3308/my.cnf<<EOF
[mysqld]
basedir=/application/mysql
datadir=/data/3308/data
port=3308
socket=/data/3308/mysql.sock
log-error=/data/3308/mysql.log
log_bin=/data/3308/mysql-bin
binlog_format=row
skip-name-resolve
server-id=18
gtid-mode=on
enforce-gtid-consistency=true
log-slave-updates=1
EOF
cat >/data/3309/my.cnf<<EOF
[mysqld]
basedir=/application/mysql
datadir=/data/3309/data
socket=/data/3309/mysql.sock
port=3309
log-error=/data/3309/mysql.log
log_bin=/data/3309/mysql-bin
binlog_format=row
skip-name-resolve
server-id=19
gtid-mode=on
enforce-gtid-consistency=true
log-slave-updates=1
EOF
cat >/data/3310/my.cnf<<EOF
[mysqld]
basedir=/application/mysql
datadir=/data/3310/data
socket=/data/3310/mysql.sock
port=3310
log-error=/data/3310/mysql.log
log_bin=/data/3310/mysql-bin
binlog_format=row
skip-name-resolve
server-id=20
gtid-mode=on
enforce-gtid-consistency=true
log-slave-updates=1
EOF
cat >/etc/systemd/system/mysqld3307.service<<EOF
[Unit]
Description=MySQL Server
Documentation=man:mysqld(8)
Documentation=http://dev.mysql.com/doc/refman/en/using-systemd.html
After=network.target
After=syslog.target
[Install]
WantedBy=multi-user.target
[Service]
User=mysql
Group=mysql
ExecStart=/application/mysql/bin/mysqld --defaults-file=/data/3307/my.cnf
LimitNOFILE = 5000
EOF
cat >/etc/systemd/system/mysqld3308.service<<EOF
[Unit]
Description=MySQL Server
Documentation=man:mysqld(8)
Documentation=http://dev.mysql.com/doc/refman/en/using-systemd.html
After=network.target
After=syslog.target
[Install]
WantedBy=multi-user.target
[Service]
User=mysql
Group=mysql
ExecStart=/application/mysql/bin/mysqld --defaults-file=/data/3308/my.cnf
LimitNOFILE = 5000
EOF
cat >/etc/systemd/system/mysqld3309.service<<EOF
[Unit]
Description=MySQL Server
Documentation=man:mysqld(8)
Documentation=http://dev.mysql.com/doc/refman/en/using-systemd.html
After=network.target
After=syslog.target
[Install]
WantedBy=multi-user.target
[Service]
User=mysql
Group=mysql
ExecStart=/application/mysql/bin/mysqld --defaults-file=/data/3309/my.cnf
LimitNOFILE = 5000
EOF
cat >/etc/systemd/system/mysqld3310.service<<EOF
[Unit]
Description=MySQL Server
Documentation=man:mysqld(8)
Documentation=http://dev.mysql.com/doc/refman/en/using-systemd.html
After=network.target
After=syslog.target
[Install]
WantedBy=multi-user.target
[Service]
User=mysql
Group=mysql
ExecStart=/application/mysql/bin/mysqld --defaults-file=/data/3310/my.cnf
LimitNOFILE = 5000
EOF
2.5 修改权限,启动多实例
chown -R mysql.mysql /data/*
systemctl start mysqld3307
systemctl start mysqld3308
systemctl start mysqld3309
systemctl start mysqld3310
mysql -S /data/3307/mysql.sock -e "show variables like 'server_id'"
mysql -S /data/3308/mysql.sock -e "show variables like 'server_id'"
mysql -S /data/3309/mysql.sock -e "show variables like 'server_id'"
mysql -S /data/3310/mysql.sock -e "show variables like 'server_id'"
2.6 节点主从规划
箭头指向谁是主库
10.0.0.51:3307 <-----> 10.0.0.52:3307
10.0.0.51:3309 ------> 10.0.0.51:3307
10.0.0.52:3309 ------> 10.0.0.52:3307
10.0.0.52:3308 <-----> 10.0.0.51:3308
10.0.0.52:3310 -----> 10.0.0.52:3308
10.0.0.51:3310 -----> 10.0.0.51:3308
2.7 分片规划
shard1:
Master:10.0.0.51:3307
slave1:10.0.0.51:3309
Standby Master:10.0.0.52:3307
slave2:10.0.0.52:3309
shard2:
Master:10.0.0.52:3308
slave1:10.0.0.52:3310
Standby Master:10.0.0.51:3308
slave2:10.0.0.51:3310
2.8 开始配置
shard1(第一组四节点)
10.0.0.51:3307 <-----> 10.0.0.52:3307
db02
mysql -S /data/3307/mysql.sock -e "grant replication slave on *.* to repl@'10.0.0.%' identified by '123';"
mysql -S /data/3307/mysql.sock -e "grant all on *.* to root@'10.0.0.%' identified by '123' with grant option;"
db01
mysql -S /data/3307/mysql.sock -e "CHANGE MASTER TO MASTER_HOST='10.0.0.52', MASTER_PORT=3307, MASTER_AUTO_POSITION=1, MASTER_USER='repl', MASTER_PASSWORD='123';"
mysql -S /data/3307/mysql.sock -e "start slave;"
mysql -S /data/3307/mysql.sock -e "show slave status\G"
db02
mysql -S /data/3307/mysql.sock -e "CHANGE MASTER TO MASTER_HOST='10.0.0.51', MASTER_PORT=3307, MASTER_AUTO_POSITION=1, MASTER_USER='repl', MASTER_PASSWORD='123';"
mysql -S /data/3307/mysql.sock -e "start slave;"
mysql -S /data/3307/mysql.sock -e "show slave status\G"
10.0.0.51:3309 ------> 10.0.0.51:3307
db01
mysql -S /data/3309/mysql.sock -e "CHANGE MASTER TO MASTER_HOST='10.0.0.51', MASTER_PORT=3307, MASTER_AUTO_POSITION=1, MASTER_USER='repl', MASTER_PASSWORD='123';"
mysql -S /data/3309/mysql.sock -e "start slave;"
mysql -S /data/3309/mysql.sock -e "show slave status\G"
10.0.0.52:3309 ------> 10.0.0.52:3307
db02
mysql -S /data/3309/mysql.sock -e "CHANGE MASTER TO MASTER_HOST='10.0.0.52', MASTER_PORT=3307, MASTER_AUTO_POSITION=1, MASTER_USER='repl', MASTER_PASSWORD='123';"
mysql -S /data/3309/mysql.sock -e "start slave;"
mysql -S /data/3309/mysql.sock -e "show slave status\G"
shard2(第二组4节点)
10.0.0.52:3308 <-----> 10.0.0.51:3308
db01
mysql -S /data/3308/mysql.sock -e "grant replication slave on *.* to repl@'10.0.0.%' identified by '123';"
mysql -S /data/3308/mysql.sock -e "grant all on *.* to root@'10.0.0.%' identified by '123' with grant option;"
db02
mysql -S /data/3308/mysql.sock -e "CHANGE MASTER TO MASTER_HOST='10.0.0.51', MASTER_PORT=3308, MASTER_AUTO_POSITION=1, MASTER_USER='repl', MASTER_PASSWORD='123';"
mysql -S /data/3308/mysql.sock -e "start slave;"
mysql -S /data/3308/mysql.sock -e "show slave status\G"
db01
mysql -S /data/3308/mysql.sock -e "CHANGE MASTER TO MASTER_HOST='10.0.0.52', MASTER_PORT=3308, MASTER_AUTO_POSITION=1, MASTER_USER='repl', MASTER_PASSWORD='123';"
mysql -S /data/3308/mysql.sock -e "start slave;"
mysql -S /data/3308/mysql.sock -e "show slave status\G"
10.0.0.52:3310 -----> 10.0.0.52:3308
db02
mysql -S /data/3310/mysql.sock -e "CHANGE MASTER TO MASTER_HOST='10.0.0.52', MASTER_PORT=3308, MASTER_AUTO_POSITION=1, MASTER_USER='repl', MASTER_PASSWORD='123';"
mysql -S /data/3310/mysql.sock -e "start slave;"
mysql -S /data/3310/mysql.sock -e "show slave status\G"
10.0.0.51:3310 -----> 10.0.0.51:3308
db01
mysql -S /data/3310/mysql.sock -e "CHANGE MASTER TO MASTER_HOST='10.0.0.51', MASTER_PORT=3308, MASTER_AUTO_POSITION=1, MASTER_USER='repl', MASTER_PASSWORD='123';"
mysql -S /data/3310/mysql.sock -e "start slave;"
mysql -S /data/3310/mysql.sock -e "show slave status\G"
2.9 检测主从状态
mysql -S /data/3307/mysql.sock -e "show slave status\G"|grep Yes
mysql -S /data/3308/mysql.sock -e "show slave status\G"|grep Yes
mysql -S /data/3309/mysql.sock -e "show slave status\G"|grep Yes
mysql -S /data/3310/mysql.sock -e "show slave status\G"|grep Yes
注:如果中间出现错误,在每个节点进行执行以下命令,然后重新搭建
mysql -S /data/3307/mysql.sock -e "stop slave; reset slave all;"
mysql -S /data/3308/mysql.sock -e "stop slave; reset slave all;"
mysql -S /data/3309/mysql.sock -e "stop slave; reset slave all;"
mysql -S /data/3310/mysql.sock -e "stop slave; reset slave all;"
2.10 MySQL分布式架构介绍
image1\. schema拆分及业务分库
2\. 垂直拆分-分库分表
3\. 水平拆分-分片
2.11 企业代表产品
360 Atlas-Sharding
Alibaba cobar
Mycat
TDDL
Heisenberg
Oceanus
Vitess
OneProxy
DRDS
3. MyCAT安装
3.1 预先安装Java运行环境
yum install -y java
3.2下载
Mycat-server-xxxxx.linux.tar.gz
http://dl.mycat.io/
3.3 解压文件
tar xf Mycat-server-1.6.5-release-20180122220033-linux.tar.gz
3.4 软件目录结构
ls
bin catlet conf lib logs version.txt
3.5 启动和连接
配置环境变量
vim /etc/profile
export PATH=/application/mycat/bin:$PATH
source /etc/profile
启动
mycat start
连接mycat:
mysql -uroot -p123456 -h 127.0.0.1 -P8066
4. 配置文件介绍
logs目录:
wrapper.log ---->mycat启动日志
mycat.log ---->mycat详细工作日志
conf目录:
schema.xml
主配置文件(读写分离、高可用、分布式策略定制、节点控制)
server.xml
mycat软件本身相关的配置
rule.xml
分片规则配置文件,记录分片规则列表、使用方法等
5.应用前环境准备
5.1 用户创建及数据库导入
db01:
mysql -S /data/3307/mysql.sock
grant all on *.* to root@'10.0.0.%' identified by '123';
source /root/world.sql
mysql -S /data/3308/mysql.sock
grant all on *.* to root@'10.0.0.%' identified by '123';
source /root/world.sql
5.2 配置文件处理
cd /application/mycat/conf
mv schema.xml schema.xml.bak
vim 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" dataNode="dn1">
</schema>
<dataNode name="dn1" dataHost="localhost1" database= "wordpress" />
<dataHost name="localhost1" maxCon="1000" minCon="10" balance="1" writeType="0" dbType="mysql" dbDriver="native" switchType="1">
<heartbeat>select user()</heartbeat>
<writeHost host="db1" url="10.0.0.51:3307" user="root" password="123">
<readHost host="db2" url="10.0.0.51:3309" user="root" password="123" />
</writeHost>
</dataHost>
</mycat:schema>
6. 配置文件简单介绍
6.1 逻辑库:schema
<schema name="TESTDB" checkSQLschema="false" sqlMaxLimit="100" dataNode="dn1">
</schema>
mycat的逻辑库"TESTDB" mycat将访问TESTDB库的请求发给dataNode="dn1"
6.2 数据节点:datanode
<dataNode name="dn1" dataHost="localhost1" database= "world" />
访问TESTDB的请求会给到dn1的world库
6.3 数据主机:datahost(w和r)
<dataHost name="localhost1" maxCon="1000" minCon="10" balance="1" writeType="0" dbType="mysql" dbDriver="native" switchType="1">
<heartbeat>select user()</heartbeat>
<writeHost host="db1" url="10.0.0.51:3307" user="root" password="123">
<readHost host="db2" url="10.0.0.52:3309" user="root" password="123" />
</writeHost>
</dataHost>
定义了后端数据库节点的信息
7. 读写分离结构配置
vim 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" dataNode="sh1">
</schema>
<dataNode name="sh1" dataHost="oldguo1" database= "world" />
<dataHost name="oldguo1" maxCon="1000" minCon="10" balance="1" writeType="0" dbType="mysql" dbDriver="native" switchType="1">
<heartbeat>select user()</heartbeat>
<writeHost host="db1" url="10.0.0.51:3307" user="root" password="123">
<readHost host="db2" url="10.0.0.51:3309" user="root" password="123" />
</writeHost>
</dataHost>
</mycat:schema>
重启mycat
mycat restart
读写分离测试
mysql -uroot -p -h 127.0.0.1 -P8066
show variables like 'server_id';
begin;
show variables like 'server_id';
commit;
总结:
以上案例实现了1主1从的读写分离功能,写操作落到主库,读操作落到从库.
如果主库宕机,从库不能在继续提供服务了。
8. 配置读写分离及高可用
[root@db01 conf]# mv schema.xml schema.xml.rw
[root@db01 conf]# vim 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" dataNode="sh1">
</schema>
<dataNode name="sh1" dataHost="haoge1" database= "world" />
<dataHost name="haoge1" maxCon="1000" minCon="10" balance="1" writeType="0" dbType="mysql" dbDriver="native" switchType="1">
<heartbeat>select user()</heartbeat>
<writeHost host="db1" url="10.0.0.51:3307" user="root" password="123">
<readHost host="db2" url="10.0.0.51:3309" user="root" password="123" />
</writeHost>
<writeHost host="db3" url="10.0.0.52:3307" user="root" password="123">
<readHost host="db4" url="10.0.0.52:3309" user="root" password="123" />
</writeHost>
</dataHost>
</mycat:schema>
真正的 writehost:负责写操作的writehost
standby writeHost(第二个writehost) :和readhost一样,只提供读服务
当写节点宕机后,后面跟的readhost也不提供服务,这时候standby的writehost就提供写服务,
后面跟的readhost提供读服务
当宕机的写节点又恢复后,他就变成了standby writeHost, standby writeHost和后面跟的readhost提供读服务
测试:
mysql -uroot -p123456 -h 127.0.0.1 -P 8066
show variables like 'server_id';
读写分离测试
mysql -uroot -p -h 127.0.0.1 -P8066
show variables like 'server_id';
show variables like 'server_id';
show variables like 'server_id';
begin;
show variables like 'server_id';
对db01 3307节点进行关闭和启动,测试读写操作
9. 配置中的属性介绍:
balance属性
负载均衡类型,目前的取值有3种:
1. balance="0", 不开启读写分离机制,所有读操作都发送到当前可用的writeHost上。
2. balance="1",全部的readHost与standby writeHost参与select语句的负载均衡,简单的说,
当双主双从模式(M1->S1,M2->S2,并且M1与 M2互为主备),正常情况下,M2,S1,S2都参与select语句的负载均衡。
3. balance="2",所有读操作都随机的在writeHost、readhost上分发。(用于读的请求量很大的情况下)
writeType属性
负载均衡类型,目前的取值有2种:
1. writeType="0", 所有写操作发送到配置的第一个writeHost,
第一个挂了切到还生存的第二个writeHost,重新启动后已切换后的为主,切换记录在配置文件中:dnindex.properties .
2. writeType=“1”,所有写操作都随机的发送到配置的writeHost,但不推荐使用
switchType属性
-1 表示不自动切换
1 默认值,自动切换
2 基于MySQL主从同步的状态决定是否切换 ,心跳语句为 show slave status
datahost其他配置
<dataHost name="localhost1" maxCon="1000" minCon="10" balance="1" writeType="0" dbType="mysql" dbDriver="native" switchType="1">
maxCon="1000":最大的并发连接数
minCon="10" :mycat在启动之后,会在后端节点上自动开启的连接线程
tempReadHostAvailable="1"
主库宕机从库可以临时提供读的功能
这个一主一从时(1个writehost,1个readhost时),可以开启这个参数,如果2个writehost,2个readhost时
<heartbeat>select user()</heartbeat> 监测心跳
10. 垂直分表
image imagemv schema.xml schema.xml.ha
vim 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" dataNode="sh1">
<table name="user" dataNode="sh1"/>
<table name="order_t" dataNode="sh2"/>
</schema>
<dataNode name="sh1" dataHost="oldguo1" database= "taobao" />
<dataNode name="sh2" dataHost="oldguo2" database= "taobao" />
<dataHost name="oldguo1" maxCon="1000" minCon="10" balance="1" writeType="0" dbType="mysql" dbDriver="native" switchType="1">
<heartbeat>select user()</heartbeat>
<writeHost host="db1" url="10.0.0.51:3307" user="root" password="123">
<readHost host="db2" url="10.0.0.51:3309" user="root" password="123" />
</writeHost>
<writeHost host="db3" url="10.0.0.52:3307" user="root" password="123">
<readHost host="db4" url="10.0.0.52:3309" user="root" password="123" />
</writeHost>
</dataHost>
<dataHost name="oldguo2" maxCon="1000" minCon="10" balance="1" writeType="0" dbType="mysql" dbDriver="native" switchType="1">
<heartbeat>select user()</heartbeat>
<writeHost host="db1" url="10.0.0.51:3308" user="root" password="123">
<readHost host="db2" url="10.0.0.51:3310" user="root" password="123" />
</writeHost>
<writeHost host="db3" url="10.0.0.52:3308" user="root" password="123">
<readHost host="db4" url="10.0.0.52:3310" user="root" password="123" />
</writeHost>
</dataHost>
</mycat:schema>
创建测试库和表:
[root@db01 conf]# mysql -S /data/3307/mysql.sock -e "create database taobao charset utf8;"
[root@db01 conf]# mysql -S /data/3308/mysql.sock -e "create database taobao charset utf8;"
[root@db01 conf]# mysql -S /data/3307/mysql.sock -e "use taobao;create table user(id int,name varchar(20))";
[root@db01 conf]# mysql -S /data/3308/mysql.sock -e "use taobao;create table order_t(id int,name varchar(20))"
[root@db01 conf]# mycat restart
11. MyCAT核心特性——分片(水平拆分)
分片:对一个"bigtable",比如说t3表
(1)行数非常多,800w
(2)访问非常频繁
分片的目的:
(1)将大数据量进行分布存储
(2)提供均衡的访问路由
分片策略:
范围 range 800w 1-400w 400w01-800w
取模 mod 取余数
枚举
哈希 hash
时间 流水
优化关联查询
全局表
ER分片
12 .范围分片
image比如说t3表
(1)行数非常多,2000w(1-1000w:sh1 1000w01-2000w:sh2)
(2)访问非常频繁,用户访问较离散
mv schema.xml schema.xml.1
vim schema.xml
<schema name="TESTDB" checkSQLschema="false" sqlMaxLimit="100" dataNode="sh1">
<table name="t3" dataNode="sh1,sh2" rule="auto-sharding-long" />
</schema>
<dataNode name="sh1" dataHost="oldguo1" database= "taobao" />
<dataNode name="sh2" dataHost="oldguo2" database= "taobao" />
vim rule.xml 分片规则
<tableRule name="auto-sharding-long">
<rule>
<columns>id</columns> id列进行rang-long规则
<algorithm>rang-long</algorithm>
</rule>
<function name="rang-long"
class="io.mycat.route.function.AutoPartitionByLong">
<property name="mapFile">autopartition-long.txt</property>
</function>
===================================
vim autopartition-long.txt
0-10=0 大于等于0小于等于10
10-20=1 大于10小于等于20
创建测试表:
mysql -S /data/3307/mysql.sock -e "use taobao;create table t3 (id int not null primary key auto_increment,name varchar(20) not null);"
mysql -S /data/3308/mysql.sock -e "use taobao;create table t3 (id int not null primary key auto_increment,name varchar(20) not null);"
测试:
重启mycat
mycat restart
mysql -uroot -p123456 -h 127.0.0.1 -P 8066
insert into t3(id,name) values(1,'a');
insert into t3(id,name) values(2,'b');
insert into t3(id,name) values(3,'c');
insert into t3(id,name) values(4,'d');
insert into t3(id,name) values(11,'aa');
insert into t3(id,name) values(12,'bb');
insert into t3(id,name) values(13,'cc');
insert into t3(id,name) values(14,'dd');
13. 取模分片(mod-long):
规则
取余分片方式:分片键(一个列)与节点数量进行取余,得到余数,将数据写入对应节点
2个节点 id=15 15除以2 余数1 放入节点号为1的节点
id=8 8除以2 余数0 放入节点号为0的节点
配置跟测试
vim schema.xml
<table name="t4" dataNode="sh1,sh2" rule="mod-long" />
取模规则 mod-long
vim rule.xml
<property name="count">2</property>
几个分片
准备测试环境
创建测试表:
mysql -S /data/3307/mysql.sock -e "use taobao;create table t4 (id int not null primary key auto_increment,name varchar(20) not null);"
mysql -S /data/3308/mysql.sock -e "use taobao;create table t4 (id int not null primary key auto_increment,name varchar(20) not null);"
重启mycat
mycat restart
测试:
mysql -uroot -p123456 -h10.0.0.52 -P8066
use TESTDB
insert into t4(id,name) values(1,'a');
insert into t4(id,name) values(2,'b');
insert into t4(id,name) values(3,'c');
insert into t4(id,name) values(4,'d');
分别登录后端节点查询数据
mysql -S /data/3307/mysql.sock
use taobao
select * from t4;
mysql -S /data/3308/mysql.sock
use taobao
select * from t4;
14. 枚举分片
t5 表
id name telnum
1 bj 1212
2 sh 22222
3 bj 3333
4 sh 44444
5 bj 5555
sharding-by-intfile
vim schema.xml 添加规则
<table name="t5" dataNode="sh1,sh2" rule="sharding-by-intfile" />
vim rule.xml
<tableRule name="sharding-by-intfile">
<rule> <columns>name</columns> 基于表的哪一列
<algorithm>hash-int</algorithm> 调用hash-int函数
</rule>
</tableRule>
columns 标识将要分片的表字段,algorithm 分片函数, 其中分片函数配置中,mapFile标识配置文件名称
<function name="hash-int" class="org.opencloudb.route.function.PartitionByFileMap">
<property name="mapFile">partition-hash-int.txt</property>
<property name="type">1</property> 指定枚举的类型(1字符串,0表示数字),默认是0
<property name="defaultNode">0</property> 设置默认节点是0节点 节点分片从0开始(写负数或者不写则不设置)
</function>
partition-hash-int.txt 配置:
bj=0
sh=1
DEFAULT_NODE=1 指定默认枚举节点(rule.xml里如果已设置会覆盖此参数,当rule.xml没有设置默认节点此参数生效)
准备测试环境
mysql -S /data/3307/mysql.sock -e "use taobao;create table t5 (id int not null primary key auto_increment,name varchar(20) not null);"
mysql -S /data/3308/mysql.sock -e "use taobao;create table t5 (id int not null primary key auto_increment,name varchar(20) not null);"
重启mycat
mycat restart
mysql -uroot -p123456 -h10.0.0.51 -P8066
use TESTDB
insert into t5(id,name) values(1,'bj');
insert into t5(id,name) values(2,'sh');
insert into t5(id,name) values(3,'bj');
insert into t5(id,name) values(4,'sh');
insert into t5(id,name) values(5,'tj');
15 . Mycat全局表
全局表使用的场景
abcd都是分片的表经常要joint表
a b c d
join
t
select t1.name ,t.x from t1
join t
select t2.name ,t.x from t2
join t
select t3.name ,t.x from t3
join t
使用场景:
如果你的业务中有些数据类似于数据字典,比如配置文件的配置,
常用业务的配置或者数据量不大很少变动的表,这些表往往不是特别大,
而且大部分的业务场景都会用到,那么这种表适合于Mycat全局表,无须对数据进行切分,
要在所有的分片上保存一份数据即可,Mycat 在Join操作中,业务表与全局表进行Join聚合会优先选择相同分片内的全局表join,
避免跨库Join,在进行数据插入操作时,mycat将把数据分发到全局表对应的所有分片执行,在进行数据读取时候将会随机获取一个节点读取数据。
全局表配置
vim schema.xml
<table name="t_area" primaryKey="id" type="global" dataNode="sh1,sh2" />
表名 主键列 类型=全局(global) 所有节点
后端数据准备
mysql -S /data/3307/mysql.sock
use taobao
create table t_area (id int not null primary key auto_increment,name varchar(20) not null);
mysql -S /data/3308/mysql.sock
use taobao
create table t_area (id int not null primary key auto_increment,name varchar(20) not null);
重启mycat
mycat restart
测试:
mysql -uroot -p123456 -h10.0.0.52 -P8066
use TESTDB
insert into t_area(id,name) values(1,'a');
insert into t_area(id,name) values(2,'b');
insert into t_area(id,name) values(3,'c');
insert into t_area(id,name) values(4,'d');
16. E-R分片
ER模型是实体关系模型,基本元素是实体、关系和属性,
Mycat 针对ER关系表的切分规则中,使得有相互依赖的表能够按照某一个规则切分到相同的节点上,避免垮库 Join 关系查询。
A
join
B
为了防止跨分片join,可以使用E-R模式
A join B
on a.xx=b.yy
<table name="A" dataNode="sh1,sh2" rule="mod-long">
<childTable name="B" joinKey="yy" parentKey="xx" />
</table>
childtable 子表B
joinkey 子表B的关联列
parentkey 驱动表A的关联列
情况一:关联列如果是驱动表设置分片的列的话,子表进行insert时也会被进行规则分片
情况二:关联列如果不是驱动表设置分片列的话,子表进行insert数据行时驱动表中要已存在此数据行里对应关联列的值的数据行
例如 insert into 子表(id,name,age) values(18,'beijing',33);
1. 情况一 进行规则的分片跟驱动表一样
2. 情况二 关联列是id的话,驱动表要存在id为18的数据行
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