atlas實現了讀寫分離，成千上萬的用戶進行寫入的操作的時候，希望引入在不同節點寫的輪詢
MyCAT基礎架構圖
MyCAT基礎環境（mysql多實例）搭建
1.1 環境准備：
-
兩台虛擬機 db01 db02
-
每台創建四個mysql實例：3307 3308 3309 3310
1.2 刪除歷史環境：
pkill mysqld \rm -rf /data/330* \mv /etc/my.cnf /etc/my.cnf.bak
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
1.4 准備DB01配置文件和啟動腳本
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
1.5 准備DB02配置文件和啟動腳本
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
1.6 修改權限，啟動多實例
chown -R mysql.mysql /data/* systemctl start mysqld3307 systemctl start mysqld3308 systemctl start mysqld3309 systemctl start mysqld3310
1.6.1 db01上檢查mysql多實例是否配置成功
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'"
1.6.2 db02上檢查mysql多實例是否配置成功
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'"
1.7 節點主從規划
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
1.8 分片規划
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
1.9 開始配置
第一組四節點結構
10.0.0.51:3307 <-----> 10.0.0.52:3307 互為主從搭建
db02執行:
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執行:
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執行:
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 （51上配置3309從3307主）
db01執行:
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（52上配置3309從3307主）
db02執行:
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"
第二組四節點結構
10.0.0.52:3308 <-----> 10.0.0.51:3308
db01執行:
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執行:
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執行:
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執行：
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執行:
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"
1.10 檢測主從狀態
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：如果中間出現錯誤，在每個節點進行執行以下命令,從第1.9步重新開始即可
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;"
MySQL分布式架構介紹
-
1. schema拆分及業務分庫
-
2. 垂直拆分-分庫分表，把在一個實例上的庫或者表查分到不同的實例上去
-
3. 水平拆分-分片 把一個表中的數據拆分到不同的實例上去
- 分布式解決的是，在讀數據庫操作的時候把查分的表練習在一起
企業代表產品
360 Atlas-Sharding Alibaba cobar Mycat TDDL Heisenberg Oceanus Vitess OneProxy DRDS
MyCAT安裝
1 預先安裝Java運行環境
yum install -y java
2 下載
Mycat-server-xxxxx.linux.tar.gz http://dl.mycat.io/
3 解壓文件
tar xf Mycat-server-1.6.7.1-release-20190627191042-linux.tar.gz
4 軟件目錄結構
ls bin catlet conf lib logs version.txt
配置文件介紹
logs目錄:
-
wrapper.log ---->mycat啟動日志
-
mycat.log ---->mycat詳細工作日志
conf目錄:
-
schema.xml 主配置文件（讀寫分離、高可用、分布式策略定制、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
-
log4j2.xml *** ,記錄日志有關
-
*.txt ,分片策略使用的規則
5 啟動和連接
配置環境變量 vim /etc/profile export PATH=/application/mycat/bin:$PATH source /etc/profile 啟動 mycat start 連接mycat： mysql -uroot -p123456 -h 127.0.0.1 -P8066
mycat基礎--高可用+讀寫分離
用戶創建及數據庫導入
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
讀寫分離配置
cd /application/mycat/conf mv schema.xml schema.xml.bak vim schema.xml
<!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>
配置文件簡單介紹
mycat 邏輯庫定義:
<schema name="TESTDB" checkSQLschema="false" sqlMaxLimit="100" dataNode="sh1">
</schema>
==================================================
數據節點定義:
<dataNode name="sh1" dataHost="oldguo1" database= "world" />
==================================================
后端主機定義:
<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>
===================================================
</mycat:schema>
說明:
-
第一個 writehost: 10.0.0.51:3307 真正的寫節點,負責寫操作
-
第二個 wrirehost: 10.0.0.52:3307 准備寫節點,負責讀,當 10.0.0.51:3307宕掉,會切換為真正的寫節點
測試:
[root@db01 conf]# mysql -uroot -p123456 -h 10.0.0.51 -P 8066
讀:
mysql> select @@server_id;
寫:
mysql> begin ;select @@server_id; commit;
配置中的屬性介紹
balance屬性
負載均衡類型，目前的取值有3種： 1. balance="0", 不開啟讀寫分離機制，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互為主備)，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。
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，重新啟動后已切換后的為主，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
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 ，心跳語句為 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"：最大的並發連接數 minCon="10" ：mycat在啟動之后，會在后端節點上自動開啟的連接線程 tempReadHostAvailable="1" 這個一主一從時（1個writehost，1個readhost時），可以開啟這個參數，如果2個writehost，2個readhost時 <heartbeat>select user()</heartbeat> 監測心跳
Mycat高級應用-分布式解決方案
垂直分表
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>
多了幾行配置
-
<table name="user" dataNode="sh1"/> 訪問user表分到 sh1數據節點
-
<table name="order_t" dataNode="sh2"/> 訪問sh2表分到sh2數據節點
- <schema name="TESTDB" checkSQLschema="false" sqlMaxLimit="100" dataNode="sh1"> 訪問其他的表默認是sh1數據節點
創建測試庫和表
[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))"
重啟mycat :
mycat restart
測試功能:
[root@db01 conf]# mysql -uroot -p123456 -h 10.0.0.51 -P 8066 mysql> use TESTDB mysql> insert into user(id ,name ) values(1,'a'),(2,'b'); mysql> commit; mysql> insert into order_t(id ,name ) values(1,'a'),(2,'b'); mysql> commit; [root@db01 ~]# mysql -S /data/3307/mysql.sock -e "show tables from taobao;" +------------------+ | Tables_in_taobao | +------------------+ | user | +------------------+ [root@db01 ~]# mysql -S /data/3308/mysql.sock -e "show tables from taobao;" +------------------+ | Tables_in_taobao | +------------------+ | order_t | +------------------+ [root@db01 ~]#
范圍分片把表查分到不同的分片上
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
配置文件局部要修改如下
配置說明
<table name="t3" dataNode="sh1,sh2" rule="auto-sharding-long" />
把表t3拆分到sh1和sh2數據節點上，安裝auto-sharding-long的策略
<?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="t3" dataNode="sh1,sh2" rule="auto-sharding-long" /> </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>
rule.xml 拆分的策略中重要的地方（默認的不用自己配置）
<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>
autopartition-long.txt 1-10條數據在1號分片，10-20在2號分片
1-10=0 10-20=1
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);"
重啟mycat
mycat restart
測試：
插入數據
mysql -uroot -p123456 -h 127.0.0.1 -P 8066 user testdb 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(10,'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'); insert into t3(id,name) values(20,'dd');
查詢測試
[root@db01 ~]# mysql -S /data/3308/mysql.sock -e "select * from taobao.t3;" [root@db01 ~]# mysql -S /data/3307/mysql.sock -e "select * from taobao.t3;"
取模分片（mod-long）
取余分片方式：分片鍵（一個列）與節點數量進行取余，得到余數，將數據寫入對應節點
配置在邏輯庫下添加以下內容
vim schema.xml <table name="t4" dataNode="sh1,sh2" rule="mod-long" />
vim rule.xml 修改為2，因為只有2個節點
<property name="count">2</property>
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);"
重啟mycat
mycat restart
添加測試數據
mysql -uroot -p123456 -h10.0.0.51 -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');
分別登錄后端節點查詢數據
mysql -S /data/3307/mysql.sock -e "select * from taobao.t4;" mysql -S /data/3308/mysql.sock -e "select * from taobao.t4;"
枚舉分片 sharding-by-intfile
t5 表結構如下
id name telnum 1 bj 1212 2 sh 22222 3 bj 3333 4 sh 44444 5 bj 5555
北京的落在一個分片，上海的落在一個分片
配置邏輯庫
vim schema.xml <table name="t5" dataNode="sh1,sh2" rule="sharding-by-intfile" />
配置規則 rule.xml 字段按照name，在函數中加入 <property name="type">1</property>支持字符串和中文
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
<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>
<property name="defaultNode">0</property>
</function>
partition-hash-int.txt 配置
bj=0 sh=1 DEFAULT_NODE=1
准備測試環境
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);"
重啟mycat
mycat restart
插入數據
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');
分別登錄后端節點查詢數據
mysql -S /data/3307/mysql.sock -e "select * from taobao.t5;" mysql -S /data/3308/mysql.sock -e "select * from taobao.t5;"
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，那么這種表適合於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。 vim schema.xml <table name="t_area" primaryKey="id" type="global" dataNode="sh1,sh2" /> 后端數據准備 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); 重啟mycat mycat restart 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');
E-R分片
A
join
B
為了防止跨分片join，可以使用E-R模式
A join B
on a.xx=b.yy
join C
on A.id=C.id
<table name="A" dataNode="sh1,sh2" rule="mod-long">
<childTable name="B" joinKey="yy" parentKey="xx" />
</table>