1，枚举分片
枚举分片：通过在配置文件中配置可能的枚举id，自己配置分片，本规则适用于特定的场景，比如有些业务需要按照省份或区县来做保存，而全国省份区县固定的
2，添加配置文件
在function.xml里面进行配置：
<code class=" hljs xml"> <!--{cke_protected}{C}%3C!%2D%2D%20%0A%20%20%20%20mapFile%E6%A0%87%E8%AF%86%E9%85%8D%E7%BD%AE%E6%96%87%E4%BB%B6%E5%90%8D%E7%A7%B0%0A%20%20%20%20type%E9%BB%98%E8%AE%A4%E5%80%BC%E4%B8%BA0%EF%BC%880%E8%A1%A8%E7%A4%BAInteger%EF%BC%8C%E9%9D%9E%E9%9B%B6%E8%A1%A8%E7%A4%BAString%EF%BC%89%0A%20%20%20%20%E9%BB%98%E8%AE%A4%E8%8A%82%E7%82%B9%E7%9A%84%E4%BD%9C%E7%94%A8%EF%BC%9A%E6%9E%9A%E4%B8%BE%E5%88%86%E7%89%87%E6%97%B6%EF%BC%8C%E5%A6%82%E6%9E%9C%E7%A2%B0%E5%88%B0%E4%B8%8D%E8%AF%86%E5%88%AB%E7%9A%84%E6%9E%9A%E4%B8%BE%E5%80%BC%EF%BC%8C%E5%B0%B1%E8%AE%A9%E5%AE%83%E8%B7%AF%E7%94%B1%E5%88%B0%E9%BB%98%E8%AE%A4%E8%8A%82%E7%82%B9%20%20%20%20%0A%20%20%20%20%2D%2D%3E--> <function name="hash-int-mc040301" class="org.opencloudb.route.function.PartitionByFileMap"> <property name="mapFile">partition-hash-int.txt</property> <property name="defaultNode">0</property> <property name="type">0</property> </function> <tablerule name="tr-hash-int-mc040301"> <rule> <columns>PROVINCE</columns> <algorithm>hash-int-mc040301</algorithm> </rule> </tablerule></code>在schema.xml里面进行配置：
autopartition-long04.txt文件的配置, 10000代表北京分片到第一个节点，10010代表上海分片到第二个节点
[root@crm_1_21 conf]# more partition-hash-int04.txt 10000=0 10010=1 [root@crm_1_21 conf]# 注意： 此配置非常简单，即预先制定可能的id范围到某个分片，所有的节点配置都是从0开始，及0代表节点1
3，建表并且录入数据
3，建表并且录入数据 CREATE TABLE ORDER040301(ID INT NOT NULL AUTO_INCREMENT PRIMARY KEY,PROVINCE INT,SN VARCHAR(64),CREATE_TIME DATETIME); mysql> CREATE TABLE ORDER040301(ID INT NOT NULL AUTO_INCREMENT PRIMARY KEY,PROVINCE INT,SN VARCHAR(64),CREATE_TIME DATETIME); Query OK, 0 rows affected (0.05 sec) mysql> INSERT INTO ORDER040301(ID,PROVINCE,SN,CREATE_TIME) VALUES(1,10000,'beijing_10006_10000',NOW()); INSERT INTO ORDER040301(ID,PROVINCE,SN,CREATE_TIME) VALUES(2,10010,'shanghai_10010',NOW()); mysql> explain INSERT INTO ORDER040301(ID,PROVINCE,SN,CREATE_TIME) VALUES(1,10000,'beijing_10006_10000',NOW()); +-----------+-------------------------------------------------------------------------------------------------+ | DATA_NODE | SQL | +-----------+-------------------------------------------------------------------------------------------------+ | dn21 | INSERT INTO ORDER040301(ID,PROVINCE,SN,CREATE_TIME) VALUES(1,10000,'beijing_10006_10000',NOW()) | +-----------+-------------------------------------------------------------------------------------------------+ 1 row in set (0.12 sec) mysql> INSERT INTO ORDER040301(ID,PROVINCE,SN,CREATE_TIME) VALUES(1,10000,'beijing_10006_10000',NOW()); Query OK, 1 row affected (0.02 sec) mysql> mysql> explain INSERT INTO ORDER040301(ID,PROVINCE,SN,CREATE_TIME) VALUES(2,10010,'shanghai_10010',NOW()); +-----------+--------------------------------------------------------------------------------------------+ | DATA_NODE | SQL | +-----------+--------------------------------------------------------------------------------------------+ | dn22 | INSERT INTO ORDER040301(ID,PROVINCE,SN,CREATE_TIME) VALUES(2,10010,'shanghai_10010',NOW()) | +-----------+--------------------------------------------------------------------------------------------+ 1 row in set (0.00 sec) mysql> INSERT INTO ORDER040301(ID,PROVINCE,SN,CREATE_TIME) VALUES(2,10010,'shanghai_10010',NOW()); Query OK, 1 row affected (0.00 sec) mysql> 4，对insert操作流程进行分析，参考mycat.log对路由过程做完整的分析
4，对insert操作流程进行分析，参考mycat.log对路由过程做完整的分析查看后台mycat.log分析如下：
开始获取连接： 02/12 23:32:11.323 DEBUG [$_NIOREACTOR-2-RW] (ServerQueryHandler.java:56) -ServerConnection [id=2, schema=TESTDB, host=127.0.0.1, user=test,txIsolation=3, autocommit=true, schema=TESTDB]INSERT INTO ORDER040301(ID,PROVINCE,SN,CREATE_TIME) VALUES(2,10010,'shanghai_10010',NOW())开始路由匹配： 02/12 23:32:11.324 DEBUG [$_NIOREACTOR-2-RW] (NonBlockingSession.java:113) -ServerConnection [id=2, schema=TESTDB, host=127.0.0.1, user=test,txIsolation=3, autocommit=true, schema=TESTDB]INSERT INTO ORDER040301(ID,PROVINCE,SN,CREATE_TIME) VALUES(2,10010,'shanghai_10010',NOW()), route={ 1 -> dn22{INSERT INTO ORDER040301(ID,PROVINCE,SN,CREATE_TIME) VALUES(2,10010,'shanghai_10010',NOW())} } rrs匹配好路由后，直接往对应的dn21节点开始执行insert数据录入操作： 02/12 23:32:11.327 DEBUG [$_NIOREACTOR-0-RW] (NonBlockingSession.java:229) -release connection MySQLConnection [id=16, lastTime=1455291131321, user=root, schema=db3, old shema=db3, borrowed=true, fromSlaveDB=false, threadId=153, charset=latin1, txIsolation=3, autocommit=true, attachment=dn22{INSERT INTO ORDER040301(ID,PROVINCE,SN,CREATE_TIME) VALUES(2,10010,'shanghai_10010',NOW())}, respHandler=SingleNodeHandler [node=dn22{INSERT INTO ORDER040301(ID,PROVINCE,SN,CREATE_TIME) VALUES(2,10010,'shanghai_10010',NOW())}, packetId=0], host=13.123.1.11, port=3327, statusSync=null, writeQueue=0, modifiedSQLExecuted=true]连接释放： 02/12 23:32:11.328 DEBUG [$_NIOREACTOR-0-RW] (PhysicalDatasource.java:403) -release channel MySQLConnection [id=16, lastTime=1455291131321, user=root, schema=db3, old shema=db3, borrowed=true, fromSlaveDB=false, threadId=153, charset=latin1, txIsolation=3, autocommit=true, attachment=null, respHandler=null, host=13.123.1.11, port=3327, statusSync=null, writeQueue=0, modifiedSQLExecuted=false]5，执行简单的查询，如果指定分片字段ID字段，则走分片查询单个分片节点
5，执行简单的查询，如果指定分片字段ID字段，则走分片查询单个分片节点mycat命令台显示结果：
mysql> explain select * from ORDER040301 t1 where PROVINCE=10000; +-----------+---------------------------------------------------------------+ | DATA_NODE | SQL | +-----------+---------------------------------------------------------------+ | dn21 | SELECT * FROM ORDER040301 t1 WHERE PROVINCE = 10000 LIMIT 100 | +-----------+---------------------------------------------------------------+ 1 row in set (0.00 sec) mysql> select * from ORDER040301 t1 where PROVINCE=10000; +----+----------+---------------------+---------------------+ | ID | PROVINCE | SN | CREATE_TIME | +----+----------+---------------------+---------------------+ | 1 | 10000 | beijing_10006_10000 | 2016-02-12 23:31:55 | +----+----------+---------------------+---------------------+ 1 row in set (0.01 sec) mysql> 查看后台mycat日志信息：
02/12 23:36:08.302 DEBUG [$_NIOREACTOR-2-RW] (ServerQueryHandler.java:56) -ServerConnection [id=2, schema=TESTDB, host=127.0.0.1, user=test,txIsolation=3, autocommit=true, schema=TESTDB]select * from ORDER040301 t1 where PROVINCE=10000 02/12 23:36:08.303 DEBUG [$_NIOREACTOR-2-RW] (EnchachePool.java:76) -SQLRouteCache miss cache ,key:TESTDBselect * from ORDER040301 t1 where PROVINCE=10000 02/12 23:36:08.304 DEBUG [$_NIOREACTOR-2-RW] (EnchachePool.java:59) -SQLRouteCache add cache ,key:TESTDBselect * from ORDER040301 t1 where PROVINCE=10000 value:select * from ORDER040301 t1 where PROVINCE=10000, route={ 1 -> dn21{SELECT * FROM ORDER040301 t1 WHERE PROVINCE = 10000 LIMIT 100} } 02/12 23:36:08.305 DEBUG [$_NIOREACTOR-2-RW] (NonBlockingSession.java:113) -ServerConnection [id=2, schema=TESTDB, host=127.0.0.1, user=test,txIsolation=3, autocommit=true, schema=TESTDB]select * from ORDER040301 t1 where PROVINCE=10000, route={ 1 -> dn21{SELECT * FROM ORDER040301 t1 WHERE PROVINCE = 10000 LIMIT 100} } rrs 02/12 23:36:08.305 DEBUG [$_NIOREACTOR-2-RW] (PhysicalDBPool.java:452) -select read source hostM2 for dataHost:m1 02/12 23:36:08.307 DEBUG [$_NIOREACTOR-1-RW] (NonBlockingSession.java:229) -release connection MySQLConnection [id=5, lastTime=1455291368304, user=root, schema=db3, old shema=db3, borrowed=true, fromSlaveDB=false, threadId=161, charset=latin1, txIsolation=3, autocommit=true, attachment=dn21{SELECT * FROM ORDER040301 t1 WHERE PROVINCE = 10000 LIMIT 100}, respHandler=SingleNodeHandler [node=dn21{SELECT * FROM ORDER040301 t1 WHERE PROVINCE = 10000 LIMIT 100}, packetId=7], host=13.123.1.11, port=3317, statusSync=org.opencloudb.mysql.nio.MySQLConnection$StatusSync@1cfa73be, writeQueue=0, modifiedSQLExecuted=false] 02/12 23:36:08.308 DEBUG [$_NIOREACTOR-1-RW] (PhysicalDatasource.java:403) -release channel MySQLConnection [id=5, lastTime=1455291368304, user=root, schema=db3, old shema=db3, borrowed=true, fromSlaveDB=false, threadId=161, charset=latin1, txIsolation=3, autocommit=true, attachment=null, respHandler=null, host=13.123.1.11, port=3317, statusSync=null, writeQueue=0, modifiedSQLExecuted=false] 6，如果分片字段范围的查询，则走所有节点去检索，哪怕只有一条数据在一个分片上，route路由也是走所有的分片进行检索查询
6，如果分片字段范围的查询，则走所有节点去检索，哪怕只有一条数据在一个分片上，route路由也是走所有的分片进行检索查询 mysql> explain select * from ORDER040301 t1 where SN='beijing_10006_10000'; +-----------+-------------------------------------------------------------------------+ | DATA_NODE | SQL | +-----------+-------------------------------------------------------------------------+ | dn21 | SELECT * FROM ORDER040301 t1 WHERE SN = 'beijing_10006_10000' LIMIT 100 | | dn22 | SELECT * FROM ORDER040301 t1 WHERE SN = 'beijing_10006_10000' LIMIT 100 | +-----------+-------------------------------------------------------------------------+ 2 rows in set (0.00 sec) mysql> mysql> select * from ORDER040301 t1 where SN='beijing_10006_10000'; +----+----------+---------------------+---------------------+ | ID | PROVINCE | SN | CREATE_TIME | +----+----------+---------------------+---------------------+ | 1 | 10000 | beijing_10006_10000 | 2016-02-12 23:31:55 | +----+----------+---------------------+---------------------+ 1 row in set (0.01 sec) mysql> 7，如果不走分片字段的查询，即使是单个数据，也要route路由所有的分片，走所有的分片进行查询
7，如果不走分片字段的查询，即使是单个数据，也要route路由所有的分片，走所有的分片进行查询 mysql> explain select * from ORDER040301 t1 where PROVINCE < 10010; +-----------+---------------------------------------------------------------+ | DATA_NODE | SQL | +-----------+---------------------------------------------------------------+ | dn21 | SELECT * FROM ORDER040301 t1 WHERE PROVINCE < 10010 LIMIT 100 | | dn22 | SELECT * FROM ORDER040301 t1 WHERE PROVINCE < 10010 LIMIT 100 | +-----------+---------------------------------------------------------------+ 2 rows in set (0.00 sec) mysql> select * from ORDER040301 t1 where PROVINCE < 10010; +----+----------+---------------------+---------------------+ | ID | PROVINCE | SN | CREATE_TIME | +----+----------+---------------------+---------------------+ | 1 | 10000 | beijing_10006_10000 | 2016-02-12 23:31:55 | +----+----------+---------------------+---------------------+ 1 row in set (0.01 sec) mysql>