Mycat讀寫分離與注意事項
最簡單的配置方式，一個主Mysql伺服器，一個從Mysql伺服器，主從關係先配置好。寫都寫到主伺服器，讀可以讀主或者從伺服器。
一、mycat配置
server。xml：
<?xml version="1.0" encoding="UTF-8"?>
<!-- - - Licensed under the Apache License, Version 2.0 (the "License");
- you may not use this file except in compliance with the License. - You
may obtain a copy of the License at - -
- - Unless required by applicable law or agreed to in writing, software -
distributed under the License is distributed on an "AS IS" BASIS, - WITHOUT
WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. - See the
License for the specific language governing permissions and - limitations
under the License. -->
<!DOCTYPE mycat:server SYSTEM "server.dtd">
<mycat:server xmlns:mycat="
<system>
<property name="useSqlStat">0</property> <!-- 1為開啟實時統計、0為關閉 -->
<property name="useGlobleTableCheck">0</property> <!-- 1為開啟全加班一致性檢測、0為關閉 -->
<property name="sequnceHandlerType">2</property>
<!-- <property name="useCompression">1</property>--> <!--1為開啟mysql壓縮協議-->
<!-- <property name="fakeMySQLVersion">5.6.20</property>--> <!--設定模擬的MySQL版本號-->
<!-- <property name="processorBufferChunk">40960</property> -->
<!--
<property name="processors">1</property>
<property name="processorExecutor">32</property>
-->
<!--預設為type 0: DirectByteBufferPool | type 1 ByteBufferArena-->
<property name="processorBufferPoolType">0</property>
<!--預設是65535 64K 用於sql解析時最大文字長度 -->
<!--<property name="maxStringLiteralLength">65535</property>-->
<!--<property name="sequnceHandlerType">0</property>-->
<!--<property name="backSocketNoDelay">1</property>-->
<!--<property name="frontSocketNoDelay">1</property>-->
<!--<property name="processorExecutor">16</property>-->
<!--
<property name="serverPort">8066</property> <property name="managerPort">9066</property>
<property name="idleTimeout">300000</property> <property name="bindIp">0.0.0.0</property>
<property name="frontWriteQueueSize">4096</property> <property name="processors">32</property> -->
<!--分散式事務開關，0為不過濾分散式事務，1為過濾分散式事務（如果分散式事務內只涉及全域性表，則不過濾），2為不過濾分散式事務,但是記錄分散式事務日誌-->
<property name="handleDistributedTransactions">0</property>
<!--
off heap for merge/order/group/limit 1開啟 0關閉
-->
<property name="useOffHeapForMerge">1</property>
<!--
單位為m
-->
<property name="memoryPageSize">1m</property>
<!--
單位為k
-->
<property name="spillsFileBufferSize">1k</property>
<property name="useStreamOutput">0</property>
<!--
單位為m
-->
<property name="systemReserveMemorySize">384m</property>
<!--是否採用zookeeper協調切換 -->
<property name="useZKSwitch">true</property>
</system>
<!-- 全域性SQL防火牆設定 -->
<!--
<firewall>
<whitehost>
<host host="127.0.0.1" user="mycat"/>
<host host="127.0.0.2" user="mycat"/>
</whitehost>
<blacklist check="false">
</blacklist>
</firewall>
-->
<user name="root">
<property name="password">123456</property>
<property name="schemas">thesisdb</property>
</user>
<user name="user">
<property name="password">user</property>
<property name="schemas">thesisdb</property>
<property name="readOnly">true</property>
</user>
</mycat:server>
-----------------------------------------------------------------------------------------------
紅色部分表示mycat的賬號為root，密碼123456，邏輯資料庫為thesisdb
-------------------------------------------------------------------------------------------------------------
schema.xml：
<?xml version="1.0"?>
<!DOCTYPE mycat:schema SYSTEM "schema.dtd">
<mycat:schema xmlns:mycat="http://io.mycat/">
<schema name="thesisdb" checkSQLschema="false" sqlMaxLimit="100" dataNode="dn1">
</schema>
<dataNode name="dn1" dataHost="localhost1" database="thesisdb" />
<dataHost name="localhost1" maxCon="1000" minCon="10" balance="1" writeType="1" dbType="mysql" dbDriver="native" switchType="1" slaveThreshold="100">
<heartbeat>select user()</heartbeat>
<writeHost host="hostM1" url="127.0.0.1:3306" user="root" password="123456">
<readHost host="hostS1" url="127.0.0.1:3307" user="root" password="123456" />
</writeHost>
</dataHost>
</mycat:schema>
紅色部分為物理伺服器，hostM1為主，hostS1為從
那麼訪問mycat資料就是使用者名稱root，密碼123456，預設埠為8066，然後就按照普通的Mysql伺服器那樣去訪問mycat。
二、SSH專案配置
一般使用框架都會用到事務，如果都要到事務那麼就都會訪問主伺服器，達不到分離的效果，因此配置事務的時候要注意區分，比如只對包含增刪改的進行事務配置：
<!-- 配置事務管理器 -->
<bean name="transactionManager" class="org.springframework.orm.hibernate4.HibernateTransactionManager">
<property name="sessionFactory" ref="sessionFactory"></property>
</bean>
<!-- 攔截器方式配置-->
<tx:advice id="transactionAdvice" transaction-manager="transactionManager">
<tx:attributes>
<tx:method name="add*" />
<tx:method name="save*" />
<tx:method name="update*" propagation="REQUIRED" />
<tx:method name="modify*" />
<tx:method name="edit*" />
<tx:method name="delete*" />
<tx:method name="remove*" />
<tx:method name="repair" />
<tx:method name="deleteAndRepair" />
</tx:attributes>
</tx:advice>
<aop:config>
<aop:pointcut id="transactionPointcut" expression="execution(* com.kpt.service..*Impl.*(..))" />
<aop:advisor pointcut-ref="transactionPointcut" advice-ref="transactionAdvice" />
</aop:config>