mycat初次简单配置分库分表

先规划下数据库的基础架构，先来个最简单基础的。

三台虚机，各安装了mysql5.7
用mycat建立逻辑数据库，建立5个表格，其中一个表格分库，一个表格做全局表，剩余三个表格每个虚机的数据库各放一个。

统计信息：

三个虚机的IP分别为:
192.168.211.138
192.168.211.139
192.168.211.142

真实的dataNode就是这三个虚机啦。

mysql的登录用户就用root@%，密码都是:Alex2010@

mycat逻辑库的名字命名为:hello
五张表格：
t1,t2,t3,t4,t5
t1做分库，t2做全局，t3放到dn1,t4放到dn2,t5放到dn3

预先需要考虑的问题:

分库的规则是什么？

先开始做吧，到哪一步再来思考。

首先配置schema.xml文件

先把配置文件备份一下
[root@mysql1 conf]# cp schema.xml schema.xml.bk2

清空配置文件
[root@mysql1 conf]# echo " " > schema.xml

开始配置：
[root@mysql1 conf]# vi schema.xml
<?xml version="1.0"?>
<!DOCTYPE mycat:schema SYSTEM "schema.dtd">
<mycat:schema xmlns:mycat="http://io.mycat/">       这是定义文件头,xml格式默认必须有

<schema name="hello" checkSQLschema="false" sqlMaxLimit="100">    定义mycat逻辑库
<!-- auto sharding by id (long) -->                               注释说明下面是分库表
<table name="t1" dataNode="dn1,dn2,dn3" rule="auto-sharding-long" />    定义t1分库

<!-- global table is auto cloned to all defined data nodes ,so can join
with any table whose sharding node is in the same data node -->     注释说明是全局表
<table name="t2" primaryKey="ID" type="global" dataNode="dn1,dn2,dn3" />       定义t2是全局表
<table name="t3" dataNode="dn1" />
<table name="t4" dataNode="dn2" />
<table name="t5" dataNode="dn3" />              这里还需要测试 定义各个分别存放在哪里

</schema>                                       结束标签

<!-- <dataNode name="dn1$0-743" dataHost="localhost1" database="db$0-743"
/> -->
<dataNode name="dn1" dataHost="mysql1" database="db1" />                  定义NODE
<dataNode name="dn2" dataHost="mysql2" database="db2" />
<dataNode name="dn3" dataHost="mysql3" database="db3" />
<dataHost name="mysql1" maxCon="1000" minCon="10" balance="0"                            定义后端连接的真实数据库
writeType="0" dbType="mysql" dbDriver="native" switchType="1"  slaveThreshold="100">
<heartbeat>select user()</heartbeat>
<!-- can have multi write hosts -->
<writeHost host="hostM1" url="192.168.211.138:3306" user="root"
password="Alex2010@">
<!-- can have multi read hosts -->
<readHost host="hostS2" url="192.168.211.138:3306" user="root" password="Alex2010@"/>
</writeHost>
</dataHost>

<dataHost name="mysql2" maxCon="1000" minCon="10" balance="0"
writeType="0" dbType="mysql" dbDriver="native" switchType="1"  slaveThreshold="100">
<heartbeat>select user()</heartbeat>
<!-- can have multi write hosts -->
<writeHost host="hostM1" url="192.168.211.139:3306" user="root"
password="Alex2010@">
<!-- can have multi read hosts -->
<readHost host="hostS2" url="192.168.211.139:3306" user="root" password="Alex2010@"/>
</writeHost>
</dataHost>

<dataHost name="mysql3" maxCon="1000" minCon="10" balance="0"
writeType="0" dbType="mysql" dbDriver="native" switchType="1"  slaveThreshold="100">
<heartbeat>select user()</heartbeat>
<!-- can have multi write hosts -->
<writeHost host="hostM1" url="192.168.211.142:3306" user="root"
password="Alex2010@">
<!-- can have multi read hosts -->
<readHost host="hostS2" url="192.168.211.142:3306" user="root" password="Alex2010@"/>
</writeHost>
</dataHost>

</mycat:schema>                 结束标签

配置server.xml

<user name="root">
<property name="password">123456</property>
<property name="schemas">TESTDB</property>            TESTDB改成自己的逻辑库，我的是hello

<!-- 表级 DML 权限设置 -->
<!--
<privileges check="false">
<schema name="TESTDB" dml="0110" >
<table name="tb01" dml="0000"></table>
<table name="tb02" dml="1111"></table>
</schema>
</privileges>
-->
</user>

<user name="user">
<property name="password">user</property>
<property name="schemas">TESTDB</property>
<property name="readOnly">true</property>
</user>

启动服务 [root@mysql1 conf]# ../bin/mycat start
Starting Mycat-server...

登录看看   [root@mysql1 conf]# mysql -uroot -p123456 -P8066 -h 127.0.0.1

稍微等一下登录，我发现马上登录会报错，说登录不上去。可以执行：
[root@mysql1 conf]# ps -ef |grep mycat
看看进程启动没有

操作看看

我这边登录成功了，参考信息如下
登录有两个端口，9066是管理端口，可以查看监控信息，8066是普通数据库登录端口，下面我是用9066端口登录，检查信息

[root@mysql1 logs]# mysql -uroot -p123456 -P9066 -h 127.0.0.1
mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 1
Server version: 5.6.29-mycat-1.6-RELEASE-20161028204710 MyCat Server (OpenCloundDB)

Copyright (c) 2000, 2017, Oracle and/or its affiliates. All rights reserved.

Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

mysql>

mysql> show @@help;
+------------------------------------------+--------------------------------------------+
| STATEMENT                                | DESCRIPTION                                |
+------------------------------------------+--------------------------------------------+
| show @@time.current                      | Report current timestamp                   |
| show @@time.startup                      | Report startup timestamp                   |
| show @@version                           | Report Mycat Server version                |
| show @@server                            | Report server status                       |
| show @@threadpool                        | Report threadPool status                   |
| show @@database                          | Report databases                           |
| show @@datanode                          | Report dataNodes                           |
| show @@datanode where schema = ?         | Report dataNodes                           |
| show @@datasource                        | Report dataSources                         |
| show @@datasource where dataNode = ?     | Report dataSources                         |
| show @@datasource.synstatus              | Report datasource data synchronous         |
| show @@datasource.syndetail where name=? | Report datasource data synchronous detail  |
| show @@datasource.cluster                | Report datasource galary cluster variables |
| show @@processor                         | Report processor status                    |
| show @@command                           | Report commands status                     |
| show @@connection                        | Report connection status                   |
| show @@cache                             | Report system cache usage                  |
| show @@backend                           | Report backend connection status           |
| show @@session                           | Report front session details               |
| show @@connection.sql                    | Report connection sql                      |
| show @@sql.execute                       | Report execute status                      |
| show @@sql.detail where id = ?           | Report execute detail status               |
| show @@sql                               | Report SQL list                            |
| show @@sql.high                          | Report Hight Frequency SQL                 |
| show @@sql.slow                          | Report slow SQL                            |
| show @@sql.resultset                     | Report BIG RESULTSET SQL                   |
| show @@sql.sum                           | Report  User RW Stat                       |
| show @@sql.sum.user                      | Report  User RW Stat                       |
| show @@sql.sum.table                     | Report  Table RW Stat                      |
| show @@parser                            | Report parser status                       |
| show @@router                            | Report router status                       |
| show @@heartbeat                         | Report heartbeat status                    |
| show @@heartbeat.detail where name=?     | Report heartbeat current detail            |
| show @@slow where schema = ?             | Report schema slow sql                     |
| show @@slow where datanode = ?           | Report datanode slow sql                   |
| show @@sysparam                          | Report system param                        |
| show @@syslog limit=?                    | Report system mycat.log                    |
| show @@white                             | show mycat white host                      |
| show @@white.set=?,?                     | set mycat white host,[ip,user]             |
| show @@directmemory=1 or 2               | show mycat direct memory usage             |
| switch @@datasource name:index           | Switch dataSource                          |
| kill @@connection id1,id2,...            | Kill the specified connections             |
| stop @@heartbeat name:time               | Pause dataNode heartbeat                   |
| reload @@config                          | Reload basic config from file              |
| reload @@config_all                      | Reload all config from file                |
| reload @@route                           | Reload route config from file              |
| reload @@user                            | Reload user config from file               |
| reload @@sqlslow=                        | Set Slow SQL Time(ms)                      |
| reload @@user_stat                       | Reset show @@sql  @@sql.sum @@sql.slow     |
| rollback @@config                        | Rollback all config from memory            |
| rollback @@route                         | Rollback route config from memory          |
| rollback @@user                          | Rollback user config from memory           |
| reload @@sqlstat=open                    | Open real-time sql stat analyzer           |
| reload @@sqlstat=close                   | Close real-time sql stat analyzer          |
| offline                                  | Change MyCat status to OFF                 |
| online                                   | Change MyCat status to ON                  |
| clear @@slow where schema = ?            | Clear slow sql by schema                   |
| clear @@slow where datanode = ?          | Clear slow sql by datanode                 |
+------------------------------------------+--------------------------------------------+
58 rows in set (0.01 sec)

以上是可以使用的监控命令，下面操作几个看看

mysql> show @@datanode;
+------+------------+-------+-------+--------+------+------+---------+------------+----------+---------+---------------+
| NAME | DATHOST    | INDEX | TYPE  | ACTIVE | IDLE | SIZE | EXECUTE | TOTAL_TIME | MAX_TIME | MAX_SQL | RECOVERY_TIME |
+------+------------+-------+-------+--------+------+------+---------+------------+----------+---------+---------------+
| dn1  | mysql1/db1 |     0 | mysql |      0 |   10 | 1000 |      94 |          0 |        0 |       0 |            -1 |
| dn2  | mysql2/db2 |     0 | mysql |      0 |   10 | 1000 |      92 |          0 |        0 |       0 |            -1 |
| dn3  | mysql3/db3 |     0 | mysql |      0 |   10 | 1000 |      94 |          0 |        0 |       0 |            -1 |
+------+------------+-------+-------+--------+------+------+---------+------------+----------+---------+---------------+
3 rows in set (0.01 sec)

三个datanode，正常。

[root@mysql1 logs]# mysql -uroot -p123456 -P8066 -h 127.0.0.1

普通口登录操作看看

mysql> show databases;
+----------+
| DATABASE |
+----------+
| hello    |
+----------+
1 row in set (0.00 sec)

mysql>

mysql> show tables;
+-----------------+
| Tables in hello |
+-----------------+
| t1              |
| t2              |
| t3              |
| t4              |
| t5              |
+-----------------+
5 rows in set (0.00 sec)

mysql> desc t1;
ERROR 1146 (42S02): Table 'db1.t1' doesn't exist
mysql>
报错，因为实际我们还没有创建表格

mysql> create table t1(id int not null,name varchar(20));
Query OK, 0 rows affected (0.66 sec)

mysql> desc t1;
+-------+-------------+------+-----+---------+-------+
| Field | Type        | Null | Key | Default | Extra |
+-------+-------------+------+-----+---------+-------+
| id    | int(11)     | NO   |     | NULL    |       |
| name  | varchar(20) | YES  |     | NULL    |       |
+-------+-------------+------+-----+---------+-------+
2 rows in set (0.08 sec)

mysql>

mysql> explain create table t1(id int not null,name varchar(20));
+-----------+---------------------------------------------------+
| DATA_NODE | SQL                                               |
+-----------+---------------------------------------------------+
| dn1       | create table t1(id int not null,name varchar(20)) |
| dn2       | create table t1(id int not null,name varchar(20)) |
| dn3       | create table t1(id int not null,name varchar(20)) |
+-----------+---------------------------------------------------+
3 rows in set (0.04 sec)

注意t1分库，三个node都会生成

mysql> create table t2(id int not null,money varchar(100));
Query OK, 0 rows affected (0.12 sec)

mysql> desc t2;
+-------+--------------+------+-----+---------+-------+
| Field | Type         | Null | Key | Default | Extra |
+-------+--------------+------+-----+---------+-------+
| id    | int(11)      | NO   |     | NULL    |       |
| money | varchar(100) | YES  |     | NULL    |       |
+-------+--------------+------+-----+---------+-------+
2 rows in set (0.08 sec)

mysql>

mysql> explain create table t2(id int not null,money varchar(100));
+-----------+-----------------------------------------------------+
| DATA_NODE | SQL                                                 |
+-----------+-----------------------------------------------------+
| dn1       | create table t2(id int not null,money varchar(100)) |
| dn2       | create table t2(id int not null,money varchar(100)) |
| dn3       | create table t2(id int not null,money varchar(100)) |
+-----------+-----------------------------------------------------+
3 rows in set (0.00 sec)

mysql>

注意t2全局表，三个node都会生成

mysql> create table t3(id int not null,bu varchar(20));
Query OK, 0 rows affected (0.04 sec)

mysql> desc t3;
+-------+-------------+------+-----+---------+-------+
| Field | Type        | Null | Key | Default | Extra |
+-------+-------------+------+-----+---------+-------+
| id    | int(11)     | NO   |     | NULL    |       |
| bu    | varchar(20) | YES  |     | NULL    |       |
+-------+-------------+------+-----+---------+-------+
2 rows in set (0.13 sec)

mysql>

mysql> explain create table t3(id int not null,bu varchar(20));
+-----------+-------------------------------------------------+
| DATA_NODE | SQL                                             |
+-----------+-------------------------------------------------+
| dn1       | create table t3(id int not null,bu varchar(20)) |
+-----------+-------------------------------------------------+
1 row in set (0.00 sec)

mysql>

t3，我们默认是设置放到node dn1上的，实现要求。

mysql> explain create table t4(id int not null,city varchar(10);
+-----------+--------------------------------------------------+
| DATA_NODE | SQL                                              |
+-----------+--------------------------------------------------+
| dn2       | create table t4(id int not null,city varchar(10) |
+-----------+--------------------------------------------------+
1 row in set (0.00 sec)

mysql> explain  create table t5(id int not null,company varchar(50));
+-----------+------------------------------------------------------+
| DATA_NODE | SQL                                                  |
+-----------+------------------------------------------------------+
| dn3       | create table t5(id int not null,company varchar(50)) |
+-----------+------------------------------------------------------+
1 row in set (0.00 sec)

mysql>

t4放到node  dn2
t5放到node  dn3

达到了我们设计的要求。