1、MyCAT基礎架構準備
MyCAT基礎架構圖
1.1 MyCAT基礎架構準備
1.1.1 環境準備：
兩臺虛擬機 db01（10.0.0.51） db02（10.0.0.52） 每臺創建四個mysql實例：3307 3308 3309 3310 1.1.2 刪除歷史環境：
pkill mysqld
rm -rf /data/330*
mv /etc/my.cnf /etc/my.cnf.bak
1.1.3 創建相關目錄初始化數據
> 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
1.1.4 準備配置文件和啓動腳本
========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
1.1.5 修改權限，啓動多實例
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'"
1.1.6 節點主從規劃 箭頭指向誰是主庫
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
1.1.7 分片規劃
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
1.1.8 開始配置
shard1
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
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"
1.1.9 檢測主從狀態
mysql -S /data/3307/mysql.sock -e "show slave status\G"|grep Running:
mysql -S /data/3308/mysql.sock -e "show slave status\G"|grep Running:
mysql -S /data/3309/mysql.sock -e "show slave status\G"|grep Running:
mysql -S /data/3310/mysql.sock -e "show slave status\G"|grep Running:
1.1.10 如果中間出現錯誤，在每個節點進行執行以下命令(2.9 狀態正確,忽略此步驟)
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;"
1.2 Mycat的安裝
MySQL分佈式架構介紹：
1.2.1 安裝java環境
yum install -y java
1.2.2 上傳到/application 並解壓
略官網：http://www.mycat.io/
1.2.3 配置文件介紹
conf:
schema.xml 主配置文件（讀寫分離、高可用、分佈式策略定製、節點控制）
server.xml mycat軟件本身相關的配置
rule.xml 分片規則配置文件,記錄分片規則列表、使用方法等
xxxx.txt 分片參數功能有關
logs目錄:
wrapper.log ---->mycat啓動日誌
mycat.log ---->mycat詳細工作日誌
1.2.4 啓動mycat
[root@db02 ~]# vim /etc/profile export PATH=/application/mycat/bin:$PATH [root@db02 ~]# source /etc/profile [root@db02 ~]# mycat start [root@db02 ~]# mysql -uroot -p123456 -h 10.0.0.52 -P8066 1.3 測試數據準備
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
1.4 核心配置文件使用介紹(schema.xml)
（1）邏輯庫定義
<schema name="TESTDB" checkSQLschema="false" sqlMaxLimit="100" dataNode="sh1">
</schema
（2）數據節點定義
（3）數據主機定義
<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>
1.5 Mycat實現讀寫分離功能
（1）配置conf文件–schema.xml
[
root@db02 /application/mycat/conf]# cat 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>
（2）Mycat重啓生效:
mycat restart
（3）模擬測試
[root@db02 /application/mycat/conf]# mysql -uroot -p123456 -h 10.0.0.52 -P8066
mysql> select @@server_id; ----模擬查詢
mysql> begin; select @@server_id;commit; —模擬寫入
1.6 讀寫分離+高可用功能
[root@db01 conf]# mv schema.xml schema.xml.rw [root@db01 conf]# vim schema.xml <?xml version="1.0"?> <mycat:schema xmlns:mycat=“http://io.mycat/”> select user() </mycat:schema> 真正的 writehost：負責寫操作的writehost standby writeHost ：和readhost一樣，只提供讀服務 當寫節點宕機後，後面跟的readhost也不提供服務，這時候standby的writehost就提供寫服務， 後面跟的readhost提供讀服務 。 測試： mysql -uroot -p123456 -h 127.0.0.1 -P 8066 show variables like ‘server_id’; 讀寫分離測試 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’; 對db01 3307節點進行關閉和啓動,測試讀寫操作
1.7 配置中的屬性介紹
1.7.1 balance屬性
負載均衡類型，目前的取值有3種： (1) balance=“0”, 不開啓讀寫分離機制，所有讀操作都發送到當前可用的writeHost上。 (2) balance=“1”，全部的readHost與standby writeHost參與select語句的負載均衡，簡單的說， 當雙主雙從模式(M1->S1，M2->S2，並且M1與 M2互爲主備)，正常情況下，M2,S1,S2都參與select語句的負載均衡。 (3) balance=“2”，所有讀操作都隨機的在writeHost、readhost上分發。 1.7.2 writeType屬性
負載均衡類型，目前的取值有2種：
（1）writeType=“0”, 所有寫操作發送到配置的第一個writeHost，
第一個掛了切到還生存的第二個writeHost，重新啓動後已切換後的爲主，切換記錄在配置文件中:dnindex.properties .
（2）writeType=“1”，所有寫操作都隨機的發送到配置的writeHost，但不推薦使用
1.7.3 switchType屬性
-1 表示不自動切換 1 默認值，自動切換 2 基於MySQL主從同步的狀態決定是否切換 ，心跳語句爲 show slave status 1.7.4 datahost其他配置
maxCon=“1000”：最大的併發連接數 minCon=“10” ：mycat在啓動之後，會在後端節點上自動開啓的連接線程 tempReadHostAvailable=“1” 這個一主一從時（1個writehost，1個readhost時），可以開啓這個參數，如果2個writehost，2個readhost時 select user() 監測心跳
1.8 垂直分表
1.8.1 修改schema.xml配置文件
mv 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>
1.8.2 創建測試庫和表:
mysql -S /data/3307/mysql.sock -e "create database taobao charset utf8;" mysql -S /data/3308/mysql.sock -e "create database taobao charset utf8;" mysql -S /data/3307/mysql.sock -e "use taobao;create table user(id int,name varchar(20))"; mysql -S /data/3308/mysql.sock -e "use taobao;create table order_t(id int,name varchar(20))"
1.8.3 重啓MyCat
mycat restart
1.8.4 進入MyCat測試，添加數據測試
mysql -uroot -p123456 -h 10.0.0.51 -P 8066 --這裏的ip地址是MyCat安裝的那個虛擬機，就是哪個虛擬機的ip地址 mysql -S /data/3307/mysql.sock -e “use taobao;show tables;” mysql -S /data/3308/mysql.sock -e “use taobao;show tables;” 1.9 MyCAT核心特性——分片（水平拆分）
分片：對一個"bigtable"，比如說t3表 (1)行數非常多，800w (2)訪問非常頻繁 分片的目的： （1）將大數據量進行分佈存儲 （2）提供均衡的訪問路由 分片策略： 範圍 range 800w 1-400w 400w01-800w 取模 mod 取餘數 枚舉 哈希 hash 時間 流水 優化關聯查詢 全局表 ER分片 1.9.1 範圍分片
（1）範圍分片參數配置
比如說t3表
(1)行數非常多，2000w（1-1000w:sh1 1000w01-2000w:sh2）
(2)訪問非常頻繁，用戶訪問較離散
cp 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
<tableRule name="auto-sharding-long">
<rule>
<columns>id</columns>
<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
11-20=1
（2）創建測試表：
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);"
（3）重啓mycat------>mycat restart
（4）登錄mycat插入數據
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');
（5）分別登入後端節點測試
mysql -S /data/3307/mysql.sock -e "use taobao;select * from t5;"
mysql -S /data/3308/mysql.sock -e "use taobao;select * from t5;"
1.9.2 取模分片（mod-long）
取餘分片方式：分片鍵（一個列）與節點數量進行取餘，得到餘數，將數據寫入對應節點
（1）取模分片參數配置
=======vim schema.xml <table name="t4" dataNode="sh1,sh2" rule="mod-long" /> ========vim rule.xml <tableRule name="mod-long"> <rule> <columns>id</columns> <algorithm>mod-long</algorithm> </rule> </tableRule> <function name="mod-long" class="io.mycat.route.function.PartitionByMod"> <!-- how many data nodes --> <property name="count">2</property> </function>
（2）創建測試表：
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);"
（3）重啓mycat
mycat restart
（4）模擬數據測試：
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');
（5）分別登錄後端節點查詢數據
mysql -S /data/3307/mysql.sock -e "use taobao;select * from t4;"
mysql -S /data/3308/mysql.sock -e "use taobao;select * from t4;"
1.9.3 枚舉分片
t5 表 id name telnum 1 bj 1212 2 sh 22222 3 bj 3333 4 sh 44444 5 bj 5555 （1）枚舉分片參數配置
=====vim schema.xml
<table name="t5" dataNode="sh1,sh2" rule="sharding-by-intfile" />
=====vim rule.xml
<tableRule name="sharding-by-intfile">
<rule> <columns>name</columns>
<algorithm>hash-int</algorithm>
</rule>
</tableRule>
<function name="hash-int" class="org.opencloudb.route.function.PartitionByFileMap">
<property name="mapFile">partition-hash-int.txt</property>
<property name="type">1</property>
</function>
======partition-hash-int.txt 配置：
bj=0
sh=1
DEFAULT_NODE=1
columns 標識將要分片的表字段，algorithm 分片函數， 其中分片函數配置中，mapFile標識配置文件名稱
（2）準備測試環境
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);"
（3）重啓mycat
mycat restart
（4）模擬數據測試
mysql -uroot -p123456 -h10.0.0.52 -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'); （5）分別登錄後端節點查詢數據
mysql -S /data/3307/mysql.sock -e "use taobao;select * from t5;"
mysql -S /data/3308/mysql.sock -e "use taobao;select * from t5;"
1.9.4 Mycat全局表
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 使用場景： 如果你的業務中有些數據類似於數據字典，比如配置文件的配置， 常用業務的配置或者數據量不大很少變動的表，這些表往往不是特別大， 而且大部分的業務場景都會用到，那麼這種表適合於Mycat全局表，無須對數據進行切分， 要在所有的分片上保存一份數據即可，Mycat 在Join操作中，業務表與全局表進行Join聚合會優先選擇相同分片內的全局表join， 避免跨庫Join，在進行數據插入操作時，mycat將把數據分發到全局表對應的所有分片執行，在進行數據讀取時候將會隨機獲取一個節點讀取數據。 （1）Mycat全局表參數配置
=====vim schema.xml
（2）後端數據準備
mysql -S /data/3307/mysql.sock -e "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 -e "use taobao;create table t_area (id int not null primary key auto_increment,name varchar(20) not null);"
（3）重啓mycat
mycat restart
（4）模擬數據測試：
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');
（5）分別登錄後端節點查詢數據
mysql -S /data/3307/mysql.sock -e “use taobao;select * from t_area;” mysql -S /data/3308/mysql.sock -e “use taobao;select * from t_area;” 2.9.5 ER分片
有一類業務，例如商品（goods）跟商品明細（goods_detail）,明細表會依賴於商品，也就是說會存在表的主 從關係，這類似業務的切分可以抽象出合適的切分規則，比如根據商品 ID 切分，總之部分業務總會可以抽象出父子關係的表。這類表適用於 ER 分片表，子表的記錄與所關聯的父表記錄存放在同一個數據分片上，避免數據 Join 跨庫操作。 goods join goods_detail on goods.id=goods_detail.good_id
（1）ER分片參數配置
=====vim schema.xml
<table name="goods" dataNode="sh1,sh2" rule="mod-long">
<childTable name="goods_detail" joinKey="goods_id" parentKey="id" />
</table>
（2）後端數據表準備
mysql -S /data/3307/mysql.sock -e "use taobao;create table goods (id int not null primary key auto_increment,name varchar(20) not null);" mysql -S /data/3308/mysql.sock -e "use taobao;create table goods (id int not null primary key auto_increment,name varchar(20) not null);" mysql -S /data/3307/mysql.sock -e "use taobao;create table goods_detail (detail_id int not null primary key auto_increment,name varchar(20) not null,goods_id int not null);" mysql -S /data/3308/mysql.sock -e "use taobao;create table goods_detail (detail_id int not null primary key auto_increment,name varchar(20) not null,goods_id int not null);"
（3）重啓mycat
mycat restart
（4）模擬數據測試：
mysql -uroot -p123456 -h10.0.0.51 -P8066 ===========goods use TESTDB insert into goods(id,name) values(1,'dn'); insert into goods(id,name) values(2,'sj'); insert into goods(id,name) values(3,'yf'); insert into goods(id,name) values(4,'bk'); ===========goods_detail use TESTDB insert into goods_detail(detail_id,name,goods_id) values(1,'電腦',1); insert into goods_detail(detail_id,name,goods_id) values(2,'500元',1); insert into goods_detail(detail_id,name,goods_id) values(3,'手機',2); insert into goods_detail(detail_id,name,goods_id) values(4,'紅色',2); insert into goods_detail(detail_id,name,goods_id) values(5,'衣服',3); insert into goods_detail(detail_id,name,goods_id) values(6,'s碼',3); insert into goods_detail(detail_id,name,goods_id) values(7,'書籍',4); insert into goods_detail(detail_id,name,goods_id) values(8,'Linux方向',4);
（5）分別登錄後端節點查詢數據
mysql -S /data/3307/mysql.sock -e "use taobao;select * from goods;select * from goods_detail;"
mysql -S /data/3308/mysql.sock -e "use taobao;select * from goods;select * from goods_detail;"
[root@db01 ~]# mysql -S /data/3307/mysql.sock -e "use taobao;select * from goods;select * from goods_detail;"
+----+------+
| id | name |
+----+------+
| 2 | sj |
| 4 | bk |
+----+------+
+-----------+-------------+----------+
| detail_id | name | goods_id |
+-----------+-------------+----------+
| 3 | 手機 | 2 |
| 4 | 紅色 | 2 |
| 7 | 書籍 | 4 |
| 8 | Linux方向 | 4 |
+-----------+-------------+----------+
[root@db01 ~]# mysql -S /data/3308/mysql.sock -e "use taobao;select * from goods;select * from goods_detail;"
+----+------+
| id | name |
+----+------+
| 1 | dn |
| 3 | yf |
+----+------+
+-----------+--------+----------+
| detail_id | name | goods_id |
+-----------+--------+----------+
| 1 | 電腦 | 1 |
| 2 | 500元 | 1 |
| 5 | 衣服 | 3 |
| 6 | s碼 | 3 |
+-----------+--------+----------+
[root@db01 ~]#
原文：https://www.jianshu.com/p/7ec2847583d4
作者：文娟_狼剩
來源：簡書