Mycat distributed database architecture solutions --Server.xml Comments

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This is a file containing Mycat file system configuration information, corresponding to the original code is SystemConfig.java. Then we do a explain to the file in our installation package, / mycat / conf in (This article is based on "Mycat distributed database architecture solutions --Linux installation and operation Mycat") follow-up, you can understand the installation directory structure. Want more detailed comparison of the profile can also go directly download mycat github source code Download: https://github.com/MyCATApache/Mycat-Server

<?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 - - http://www.apache.org/licenses/LICENSE-2.0
    - - 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="http://io.mycat/">
    <!-- Mycat中有两个重要的标签，分别是user、system -->
    <!-- system标签与系统配置有关 -->
    <system>
        <!-- 配置该属性的时候一定要保证mycat的字符集和mysql 的字符集是一致的。
        如果需要配置特殊字符集，如：utf8mb4，则可以在index_to_charset.properties中配置，配置格式
        为“ID=字符集”,例如：“224=utf8mb4”-->
        <property name="charset">utf8</property>
        <!-- 1为开启实时统计、0为关闭 -->
        <property name="useSqlStat">0</property>
        <!-- 0为需要密码登陆、1为不需要密码登陆 ,默认为0，设置为1则需要指定默认账户-->
        <property name="nonePasswordLogin">0</property>
        <property name="useHandshakeV10">1</property>
        <!-- 1为开启全加班一致性检测、0为关闭 -->
        <property name="useGlobleTableCheck">0</property>
        <!-- SQL 执行超时 单位:秒-->
        <property name="sqlExecuteTimeout">300</property>
        <!-- 指定使用 Mycat 全局序列的类型。 0 为本地文件方式，1 为数据库方式，2 为时间戳序列方式，3 为分布式ZK ID 生成器，4 为 zk 递增 id 生成。 -->
        <property name="sequnceHandlerType">5</property>
        <!-- 必须带有MYCATSEQ_或者 mycatseq_进入序列匹配流程 注意MYCATSEQ_有空格的情况 -->
        <property name="sequnceHandlerPattern">(?:(\s*next\s+value\s+for\s*MYCATSEQ_(\w+))(,|\)|\s)*)+</property>
        <!-- 子查询中存在关联查询的情况下,检查关联字段中是否有分片字段 .默认 false -->
        <property name="subqueryRelationshipCheck">false</property>
        <property name="sequenceHanlderClass">io.mycat.route.sequence.handler.HttpIncrSequenceHandler</property>
        <!-- 默认为type 0: DirectByteBufferPool | type 1 ByteBufferArena | type 2 NettyBufferPool -->
        <property name="processorBufferPoolType">0</property>
        <!-- 分布式事务开关，0为不过滤分布式事务，1为过滤分布式事务（如果分布式事务内只涉及全局表，则不过滤），2为不过滤分布式事务,但是记录分布式事务日志-->
        <property name="handleDistributedTransactions">0</property>
        <!-- off heap for merge/order/group/limit      1开启   0关闭 -->
        <property name="useOffHeapForMerge">0</property>
        <!-- 单位为m -->
        <property name="memoryPageSize">64k</property>
        <!-- 单位为k -->
        <property name="spillsFileBufferSize">1k</property>
        <property name="useStreamOutput">0</property>
        <!-- 单位为m -->
        <property name="systemReserveMemorySize">384m</property>
        <!--是否采用zookeeper协调切换  -->
        <property name="useZKSwitch">false</property>
        <!--如果为 true的话 严格遵守隔离级别,不会在仅仅只有select语句的时候在事务中切换连接-->
        <property name="strictTxIsolation">false</property>
        <property name="useZKSwitch">true</property>
    </system>
    
    <!-- user标签主要用于定义登录Mycat的用户和权限 -->
    <!-- name="root" 定义登录用户名 -->
    <user name="root" defaultAccount="true">
        <!-- 定义了登录密码 -->
        <property name="password">123456</property>
        <property name="schemas">scott</property>
        <!-- true：只读 false：读写都有 -->
        <property name="readOnly">true</property>
        <!-- 限制前端的整体连接数量，如果值为0或者不设置，则表示不限制连接数量 -->
        <property name="banchmark">1000</property>
        <!-- 0不对密码进行加密，1对密码进行加密 -->
        <property name="usingDecrypt">0</property>
    </user>
    <user name="user">
        <property name="password">user</property>
        <property name="schemas">scott</property>
        <property name="readOnly">true</property>
    </user>
</mycat:server>

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