枚举分片
有一张t5表，我就想按区域进行枚举分片，
1使用rule="sharding-by-intfile"策略对t5表进行枚举分片（sh1片he sh2片）：
[root@db01 ~]# vim /application/mycat/conf/schema.xml
[root@db01 ~]# cat /application/mycat/conf/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="t3" dataNode="sh1,sh2" rule="auto-sharding-long" />
<table name="t5" dataNode="sh1,sh2" rule="sharding-by-intfile" />
</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="10.0.0.201:3307" user="root" password="123">
<readHost host="db2" url="10.0.0.201:3309" user="root" password="123" />
</writeHost>
<writeHost host="db3" url="10.0.0.202:3307" user="root" password="123">
<readHost host="db4" url="10.0.0.202:3309" 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="10.0.0.201:3308" user="root" password="123">
<readHost host="db2" url="10.0.0.201:3310" user="root" password="123" />
</writeHost>
<writeHost host="db3" url="10.0.0.202:3308" user="root" password="123">
<readHost host="db4" url="10.0.0.202:3310" user="root" password="123" />
</writeHost>
</dataHost>
</mycat:schema>
[root@db01 ~]#
2因为t5表我们用省的名字name作为列，而不是id，所以我们需要修改一下规则：
[root@db01 ~]# vim /application/mycat/conf/rule.xml
<tableRule name="sharding-by-intfile">
<rule>
<columns>sharding_id</columns>
<algorithm>hash-int</algorithm>
</rule>
</tableRule>
替换为：
<tableRule name="sharding-by-intfile">
<rule>
<columns>name</columns>
<algorithm>hash-int</algorithm>
</rule>
</tableRule>
然后接着往下找hash-int这个方法：
<function name="hash-int"
class="io.mycat.route.function.PartitionByFileMap">
<property name="mapFile">partition-hash-int.txt</property>
</function>
发现负责分片策略的文件是partition-hash-int.txt
由于hash-int这个函数不支持字符串，为了让其支持，我们需要添加一行代码：
<function name="hash-int"
class="io.mycat.route.function.PartitionByFileMap">
<property name="mapFile">partition-hash-int.txt</property>
<property name="type">1</property>
<property name="defaultNode">0</property>
</function>
接下来我们就在partition-hash-int.txt文件中编写分片策略(bj落到0号分片，sh落到1号分片，其他的默认落到1号分片)
[root@db01 conf]# vim /application/mycat/conf/partition-hash-int.txt
bj=0
sh=1
DEFAULT_NODE=1
3准备测试表重启mycat并进行测试：
[root@db01 conf]# 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);"
[root@db01 conf]# 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);"
[root@db01 conf]# mycat restart
Stopping Mycat-server...
Mycat-server was not running.
Starting Mycat-server...
[root@db01 conf]# mysql -uroot -p123456 -h10.0.0.201 -P8066
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 4
Server version: 5.6.29-mycat-1.6.5-release-20180122220033 MyCat Server (OpenCloundDB)
Copyright (c) 2000, 2019, 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> use TESTDB
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A
Database changed
mysql> insert into t5(id,name) values(1,'bj');
Query OK, 1 row affected (2.02 sec)
mysql> insert into t5(id,name) values(2,'sh');
Query OK, 1 row affected (0.15 sec)
mysql> insert into t5(id,name) values(3,'bj');
Query OK, 1 row affected (0.05 sec)
mysql> insert into t5(id,name) values(4,'sh');
Query OK, 1 row affected (0.11 sec)
mysql> insert into t5(id,name) values(5,'tj');
Query OK, 1 row affected (0.07 sec)
mysql> select * from t5;
+----+------+
| id | name |
+----+------+
| 1 | bj |
| 2 | sh |
| 3 | bj |
| 4 | sh |
| 5 | tj |
+----+------+
5 rows in set (0.32 sec)
mysql>
4分别登录后端节点查询数据看看是否是按照我们要求进行分片的：
[root@db01 conf]# mysql -S /data/3307/mysql.sock -e "select * from taobao.t5;"
[root@db01 conf]# mysql -S /data/3308/mysql.sock -e "select * from taobao.t5;"
报错：sh1可以获取数据，sh2死活得不到数据，
解决：
结论是mycat程序异常造成的，需要将程序彻底关掉后再重启，然后删除旧的测试表，再进行测试
[root@db01 conf]# mysql -S /data/3308/mysql.sock -e "delete from taobao.t5;"
[root@db01 conf]# mysql -S /data/3308/mysql.sock -e "delete from taobao.t5;"
[root@db01 conf]# mycat stop
[root@db01 conf]# ps -ef |grep mycat
[root@db01 conf]# kill -9 1178
[root@db01 conf]# ps -ef |grep mycat
[root@db01 conf]# kill -9 1180
[root@db01 conf]# ps -ef |grep mycat
[root@db01 conf]# ps -ef |grep java
[root@db01 conf]# ps -ef |grep mycat
[root@db01 conf]# mycat start
[root@db01 conf]# netstat -tulnp
[root@db01 conf]# vim ../logs/wrapper.log
[root@db01 conf]# mycat restart
[root@db01 conf]# netstat -tulnp
[root@db01 conf]# mycat stop
[root@db01 conf]# netstat -tulnp
[root@db01 conf]# mycat start
[root@db01 conf]# netstat -tulnp
[root@db01 conf]# mysql -uroot -p123456 -h 127.0.0.1 -P8066
mysql> use TESTDB
mysql> insert into t5(id,name) values(33,'sh');
mysql> insert into t5(id,name) values(34,'bj');
[root@db01 conf]# mysql -S /data/3308/mysql.sock -e "select * from taobao.t5;"
[root@db01 conf]# mysql -S /data/3307/mysql.sock -e "select * from taobao.t5;"
