MySQL之九—分散式架構（Mycat/DBLE）
- 2021 年 3 月 3 日
- 筆記
雙主雙從結構
MyCAT基礎架構準備
準備環境
環境準備：
兩台虛擬機 db01 db02
每台創建四個mysql實例：3307 3308 3309 3310
刪除歷史環境
pkill mysqld rm -rf /data/330* \mv /etc/my.cnf /etc/my.cnf.bak
初始化數據
mkdir /data/33{07..10}/data -p
mysqld --initialize-insecure --user=mysql --datadir=/data/3307/data --basedir=/usr/local/mysql
mysqld --initialize-insecure --user=mysql --datadir=/data/3308/data --basedir=/usr/local/mysql
mysqld --initialize-insecure --user=mysql --datadir=/data/3309/data --basedir=/usr/local/mysql
mysqld --initialize-insecure --user=mysql --datadir=/data/3310/data --basedir=/usr/local/mysql
配置文件
========db01==============
cat >/data/3307/my.cnf<<EOF
[mysqld]
basedir=/usr/local/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=/usr/local/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=/usr/local/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=/usr/local/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=//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=/usr/local/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=//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=/usr/local/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=//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=/usr/local/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=//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=/usr/local/mysql/bin/mysqld --defaults-file=/data/3310/my.cnf
LimitNOFILE = 5000
EOF
========db02===============
cat >/data/3307/my.cnf<<EOF
[mysqld]
basedir=/usr/local/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=/usr/local/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=/usr/local/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=/usr/local/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=//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=/usr/local/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=//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=/usr/local/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=//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=/usr/local/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=//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=/usr/local/mysql/bin/mysqld --defaults-file=/data/3310/my.cnf
LimitNOFILE = 5000
EOF
啟動多實例
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'"
配置主從環境
shard1 10.0.0.51:3307 <-----> 10.0.0.52:3307 # db02 mysql -S /data/3307/mysql.sock -e "create user repl@'10.0.0.%' identified with mysql_native_password by '123'; grant replication slave on *.* to repl@'10.0.0.%'; " mysql -S /data/3307/mysql.sock -e "create user root@'10.0.0.%' identified with mysql_native_password by '123'; grant all on *.* to root@'10.0.0.%'; " # 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"|grep Running # 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" |grep Running 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"|grep Running 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"|grep Running ==================================================================== # shard2 ## 10.0.0.52:3308 <-----> 10.0.0.51:3308 # db01 mysql -S /data/3308/mysql.sock -e "create user repl@'10.0.0.%' identified with mysql_native_password by '123'; grant replication slave on *.* to repl@'10.0.0.%';" mysql -S /data/3308/mysql.sock -e "create user root@'10.0.0.%' identified with mysql_native_password by '123'; grant all on *.* to root@'10.0.0.%'; " # 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" |grep Running # 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"|grep Running ## 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" |grep Running ##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"|grep Running
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
註：如果中間出現錯誤，在每個節點進行執行以下命令，從配置主從環境開始執行 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;”
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
MySQL分散式架構介紹
1. schema拆分及業務分庫
2. 垂直拆分-分庫分表
3. 水平拆分-分片
企業代表產品
360 Atlas-Sharding
Alibaba cobar
Mycat
TDDL
Heisenberg
Oceanus
Vitess
OneProxy
DRDS
MyCAT安裝
開源組織和社區開發人員，在淘寶cobar(TDDL)基礎上二次開發，Mycat後來被愛可生改寫成了DBLE
安裝Java運行環境
yum install -y java
下載
解壓文件
[root@db02 opt]#rz [root@db02 opt]# tar xf Mycat-server-1.6.7.4-release-20200105164103-linux_.tar.gz
軟體目錄結構
ls bin catlet conf lib logs version.txt
啟動和連接
配置環境變數
[root@db02 opt]#vim /etc/profile
export PATH=/opt/mycat/bin:$PATH
[root@db02 opt]#source /etc/profile
啟動
[root@db02 opt]#mycat start
連接mycat：
[root@db02 opt]#mysql -uroot -p123456 -h10.0.0.52 -P8066 --default-auth=mysql_native_password
8.0之前[root@db02 opt]#mysql -uroot -p123456 -h10.0.0.52 -P8066
配置文件介紹
bin 目錄
程式目錄
conf
配置文件目錄
schema.xml
主配置文件：節點資訊、讀寫分離、高可用設置、調用分片策略..
rule.xml
分片策略的定義、功能、使用用方法
server.xml
mycat服務有關配置： 用戶、網路、許可權、策略、資源...
xx.txt文件
分片參數定義文件
log4j2.xml
Mycat 相關日誌記錄配置
logs
wrapper.log: 啟動日誌
mycat.log : 工作日誌
應用環境準備
用戶創建及資料庫導入
schema.xml配置文件結構
[root@db02 conf]# cd /opt/mycat/conf/
[root@db02 conf]#mv schema.xml schema.xml.bak
[root@db02 conf]#vim schema.xml
<?xml version="1.0"?>
<!DOCTYPE mycat:schema SYSTEM "schema.dtd">
<mycat:schema xmlns:mycat="//io.mycat/">
<schema name="TESTDB" checkSQLschema="false" sqlMaxLimit="100" dataNode="dn1">
</schema>
<dataNode name="dn1" dataHost="localhost1" database= "world" />
<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>
########################測試環境準備
[root@db02 conf]# mysql -S /data/3307/mysql.sock -e "source /root/world.sql"
[root@db02 conf]# mysql -S /data/3308/mysql.sock -e "source /root/world.sql"
[root@db02 conf]# mycat restart 重啟mycat
######################## 讀寫分離測試
# 測試讀
mysql -uroot -p123456 -h 10.0.0.52 -P8066 --default-auth=mysql_native_password -e "select @@server_id;"
mysql: [Warning] Using a password on the command line interface can be insecure.
+-------------+
| @@server_id |
+-------------+
| 9 |
+-------------+
# 測試寫
mysql -uroot -p123456 -h 10.0.0.52 -P8066 --default-auth=mysql_native_password -e "begin ; select @@server_id;commit;"
mysql: [Warning] Using a password on the command line interface can be insecure.
+-------------+
| @@server_id |
+-------------+
| 7 |
+-------------+
############################總結：
以上案例實現了1主1從的讀寫分離功能，寫操作落到主庫，讀操作落到從庫.如果主庫宕機，從庫不能在繼續提供服務了。
配置文件詳細介紹
邏輯庫：schema
<schema name="TESTDB" checkSQLschema="false" sqlMaxLimit="100" dataNode="dn1"> </schema>
數據節點:datanode
<dataNode name="dn1" dataHost="localhost1" database= "world" />
數據主機：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>
配置讀寫分離及高可用
[root@db02 conf]# mv schema.x
[root@db02 conf]# mv schema.xml schema.xml.rw
[root@db02 conf]# vim schema.xml
<?xml version="1.0"?>
<!DOCTYPE mycat:schema SYSTEM "schema.dtd">
<mycat:schema xmlns:mycat="//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>
<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>
ml schema.xml.rw
[root@db02 conf]# vim schema.xml
<?xml version="1.0"?>
<!DOCTYPE mycat:schema SYSTEM "schema.dtd">
<mycat:schema xmlns:mycat="//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>
<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：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節點進行關閉和啟動,測試讀寫操作
重啟
[root@db02 conf]#mycat restart
測試讀(三讀）
[root@db02 conf]# mysql -uroot -p123456 -h 10.0.0.52 -P8066 --default-auth=mysql_native_password -e "select @@server_id;"
+-------------+
| @@server_id |
+-------------+
| 19 |
+-------------+
+-------------+
| @@server_id |
+-------------+
| 17 |
+-------------+
+-------------+
| @@server_id |
+-------------+
| 9 |
+-------------+
測試寫（一寫）
[root@db02 conf]# mysql -uroot -p123456 -h 10.0.0.52 -P8066 --default-auth=mysql_native_password -e "begin ; select @@server_id;commit;" +-------------+ | @@server_id | +-------------+ | 7 | +-------------+
測試高可用
[root@db01 ~]# systemctl stop mysqld3307 [root@db02 conf]# mysql -uroot -p123456 -h10.0.0.52 -P8066 --default-auth=mysql_native_password -e "select @@server_id;" +-------------+ | @@server_id | +-------------+ | 19 | +-------------+ [root@db02 conf]# mysql -uroot -p123456 -h10.0.0.52 -P8066 --default-auth=mysql_native_password -e "begin ; select @@server_id;commit;" +-------------+ | @@server_id | +-------------+ | 17 | +-------------+ [root@db01 ~]# systemctl start mysqld3307 [root@db02 conf]# mysql -uroot -p123456 -h10.0.0.52 -P8066 --default-auth=mysql_native_password -e "select @@server_id;" +-------------+ | @@server_id | +-------------+ | 19 | +-------------+ +-------------+ | @@server_id | +-------------+ | 7 | +-------------+ +-------------+ | @@server_id | +-------------+ | 9 | +-------------+ [root@db02 conf]# mysql -uroot -p123456 -h10.0.0.52 -P8066 --default-auth=mysql_native_password -e "begin ; select @@server_id;commit;" +-------------+ | @@server_id | +-------------+ | 17 | +-------------+
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"，默認參數 三讀一寫 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，重新啟動後已切換後的為主，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在啟動之後，會在後端節點上自動開啟的連接執行緒 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 分散式架構—-垂直分表
taobao庫: user （sh1），order_t(sh2) ,others(sh3)
[root@db02 conf]# mv schema.xml schema.xml.ha
[root@db02 conf]# vim schema.xml
<?xml version="1.0"?>
<!DOCTYPE mycat:schema SYSTEM "schema.dtd">
<mycat:schema xmlns:mycat="//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>
創建測試庫和表
[root@db02 conf]# mysql -S /data/3307/mysql.sock -e "create database taobao charset utf8;" [root@db02 conf]# mysql -S /data/3308/mysql.sock -e "create database taobao charset utf8;" [root@db02 conf]# mysql -S /data/3307/mysql.sock -e "use taobao;create table user(id int,name varchar(20))"; [root@db02 conf]# mysql -S /data/3308/mysql.sock -e "use taobao;create table order_t(id int,name varchar(20))";
重啟mycat
[root@db02 conf]# mycat restart
mycat數據插入
[root@db02 conf]# mysql -uroot -p123456 -h 10.0.0.52 -P 8066 --default-auth=mysql_native_password insert into user values(1,'a'); insert into user values(2,'b'); insert into user values(3,'c'); commit; insert into order_t values(1,'x'),(2,'y'); commit; show databases; use TESTDB; show tables select * from order_t; +------+------+ | id | name | +------+------+ | 1 | x | | 2 | y | +------+------+ 2 rows in set (0.05 sec) mysql> select * from user; +------+------+ | id | name | +------+------+ | 1 | a | | 2 | b | | 3 | c | +------+------+ [root@db02 conf]# mysql -S /data/3307/mysql.sock -e "show tables from taobao" +------------------+ | Tables_in_taobao | +------------------+ | user | +------------------+ [root@db02 conf]# mysql -S /data/3308/mysql.sock -e "show tables from taobao" +------------------+ | Tables_in_taobao | +------------------+ | order_t | +------------------+ [root@db02 conf]# mysql -S /data/3307/mysql.sock -e "select * from taobao.user" +------+------+ | id | name | +------+------+ | 1 | a | | 2 | b | | 3 | c | +------+------+ [root@db02 conf]# mysql -S /data/3308/mysql.sock -e "select * from taobao.order_t" +------+------+ | id | name | +------+------+ | 1 | x | | 2 | y | +------+------
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）將大數據量進行分布存儲
（2）提供均衡的訪問路由
分片策略：
幾乎融合經典業務中大部分的分片策略。Mycat已經開發了相應演算法，非常方便調用。
範圍分片
取模
枚舉
日期
HASH
等。
分片鍵： 作為分片條件的列。
範圍分片(range)
比如說t3表
行數非常多，2000w（1-1000w:sh1 1000w01-2000w:sh2）
訪問非常頻繁，用戶順序訪問較多
訂製分片策略
[root@db02 conf]#cp schema.xml schema.xml.1
[root@db02 conf]#vim schema.xml
<table name="user" dataNode="sh1"/>
<table name="order_t" dataNode="sh2"/>
下方添加：
<table name="t3" dataNode="sh1,sh2" rule="auto-sharding-long" />
</schema>
定義和使用分片策略
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>
定義範圍
[root@db02 conf]#vim autopartition-long.txt 0-10=0 10-20=1
創建測試表
[root@db02 conf]# 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);" [root@db02 conf]# 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並測試
[root@db02 conf]# mycat restart
[root@db02 conf]# mysql -uroot -p123456 -h 10.0.0.52 -P 8066 --default-auth=mysql_native_password
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');
mysql> show databases;
+----------+
| DATABASE |
+----------+
| TESTDB |
+----------+
mysql> use TESTDB;
mysql> show tables;
+------------------+
| Tables_in_taobao |
+------------------+
| order_t |
| t3 |
| user |
+------------------+
#####邏輯上合併
mysql> select * from t3;
+----+------+
| id | name |
+----+------+
| 1 | a |
| 2 | b |
| 3 | c |
| 4 | d |
| 11 | aa |
| 12 | bb |
| 13 | cc |
| 14 | dd |
+----+------+
###物理上分開
[root@db02 conf]# mysql -S /data/3308/mysql.sock -e "select * from taobao.t3"
+----+------+
| id | name |
+----+------+
| 11 | aa |
| 12 | bb |
| 13 | cc |
| 14 | dd |
+----+------+
[root@db02 conf]# mysql -S /data/3307/mysql.sock -e "select * from taobao.t3"
+----+------+
| id | name |
+----+------+
| 1 | a |
| 2 | b |
| 3 | c |
| 4 | d |
+