mycat 連續分片 -> 按日期（天）分片
阿新 • • 發佈：2019-02-15
1，按日期（天）分片
按日期（天）分片：從開始日期算起，按照天數來分片
例如，從2016-01-01，每10天一個分片
注意事項：需要提前將分片規劃好，建好，否則有可能日期超出實際配置分片數
2，新增配置檔案
在function.xml裡面進行配置：
<function name="sharding-by-date" class="org.opencloudb.route.function.PartitionByDate">
<property name="dateFormat">yyyy-MM-dd</property> 在schema.xml裡面進行配置：
<table name="ORDER0402" primaryKey="ID" dataNode="dn21,dn22" rule="sharding-by-date-tr04" 3，建表並且錄入資料
CREATE TABLE ORDER0402(ID INT NOT NULL AUTO_INCREMENT PRIMARY KEY,PROVINCE VARCHAR(16),SN VARCHAR(64),CREATE_TIME DATETIME);
mysql> CREATE TABLE ORDER0402(ID INT NOT NULL AUTO_INCREMENT PRIMARY KEY,PROVINCE VARCHAR(16),SN VARCHAR(64),CREATE_TIME DATETIME);
Query OK, 0 rows affected (0.05 sec)
mysql>
INSERT INTO ORDER0402(ID,PROVINCE,SN,CREATE_TIME) VALUES(10001,'shanghai','shanghai10006_2016-01-03','2016-01-03');
INSERT INTO ORDER0402(ID,PROVINCE,SN,CREATE_TIME) VALUES(5000001,'shanghai','shanghai10006_2016-01-13','2016-01-13');
mysql> CREATE TABLE ORDER0402(ID INT NOT NULL AUTO_INCREMENT PRIMARY KEY,PROVINCE VARCHAR(16),SN VARCHAR(64),CREATE_TIME DATETIME);
Query OK, 0 rows affected (0.06 sec)
mysql> explain INSERT INTO ORDER0402(ID,PROVINCE,SN,CREATE_TIME) VALUES(10001,'shanghai','shanghai10006_2016-01-03','2016-01-03');
+-----------+--------------------------------------------------------------------------------------------------------------------+
| DATA_NODE | SQL |
+-----------+--------------------------------------------------------------------------------------------------------------------+
| dn21 | INSERT INTO ORDER0402(ID,PROVINCE,SN,CREATE_TIME) VALUES(10001,'shanghai','shanghai10006_2016-01-03','2016-01-03') |
+-----------+--------------------------------------------------------------------------------------------------------------------+
1 row in set (0.11 sec)
mysql> INSERT INTO ORDER0402(ID,PROVINCE,SN,CREATE_TIME) VALUES(10001,'shanghai','shanghai10006_2016-01-03','2016-01-03');
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> explain INSERT INTO ORDER0402(ID,PROVINCE,SN,CREATE_TIME) VALUES(5000001,'shanghai','shanghai10006_2016-01-13','2016-01-13');
+-----------+----------------------------------------------------------------------------------------------------------------------+
| DATA_NODE | SQL |
+-----------+----------------------------------------------------------------------------------------------------------------------+
| dn22 | INSERT INTO ORDER0402(ID,PROVINCE,SN,CREATE_TIME) VALUES(5000001,'shanghai','shanghai10006_2016-01-13','2016-01-13') |
+-----------+----------------------------------------------------------------------------------------------------------------------+
1 row in set (0.01 sec)
mysql> INSERT INTO ORDER0402(ID,PROVINCE,SN,CREATE_TIME) VALUES(5000001,'shanghai','shanghai10006_2016-01-13','2016-01-13');
Query OK, 1 row affected (0.01 sec)
mysql> 4，對insert操作流程進行分析，參考mycat.log對路由過程做完整的分析
檢視後臺mycat.log分析如下：
開始獲取連線：
02/12 22:23:26.386 DEBUG [$_NIOREACTOR-2-RW] (ServerQueryHandler.java:56) -ServerConnection [id=1, schema=TESTDB, host=127.0.0.1, user=test,txIsolation=3, autocommit=true, schema=TESTDB]INSERT INTO ORDER0402(ID,PROVINCE,SN,CREATE_TIME) VALUES(5000001,'shanghai','shanghai10006_2016-01-13','2016-01-13')
開始路由匹配：
02/12 22:23:26.388 DEBUG [$_NIOREACTOR-2-RW] (NonBlockingSession.java:113) -ServerConnection [id=1, schema=TESTDB, host=127.0.0.1, user=test,txIsolation=3, autocommit=true, schema=TESTDB]INSERT INTO ORDER0402(ID,PROVINCE,SN,CREATE_TIME) VALUES(5000001,'shanghai','shanghai10006_2016-01-13','2016-01-13'), route={
1 -> dn22{INSERT INTO ORDER0402(ID,PROVINCE,SN,CREATE_TIME) VALUES(5000001,'shanghai','shanghai10006_2016-01-13','2016-01-13')}
匹配好路由後，直接往對應的dn22節點開始執行insert資料錄入操作：
02/12 22:23:26.403 DEBUG [$_NIOREACTOR-1-RW] (NonBlockingSession.java:229) -release connection MySQLConnection [id=17, lastTime=1455287006372, user=root, schema=db3, old shema=db3, borrowed=true, fromSlaveDB=false, threadId=90, charset=latin1, txIsolation=3, autocommit=true, attachment=dn22{INSERT INTO ORDER0402(ID,PROVINCE,SN,CREATE_TIME) VALUES(5000001,'shanghai','shanghai10006_2016-01-13','2016-01-13')}, respHandler=SingleNodeHandler [node=dn22{INSERT INTO ORDER0402(ID,PROVINCE,SN,CREATE_TIME) VALUES(5000001,'shanghai','shanghai10006_2016-01-13','2016-01-13')}, packetId=0], host=13.23.1.11, port=3327, statusSync=null, writeQueue=0, modifiedSQLExecuted=true]
操作完成，開始釋放連線：
02/12 22:23:26.404 DEBUG [$_NIOREACTOR-1-RW] (PhysicalDatasource.java:403) -release channel MySQLConnection [id=17, lastTime=1455287006372, user=root, schema=db3, old shema=db3, borrowed=true, fromSlaveDB=false, threadId=90, charset=latin1, txIsolation=3, autocommit=true, attachment=null, respHandler=null, host=13.23.1.11, port=3327, statusSync=null, writeQueue=0, modifiedSQLExecuted=false]5，執行簡單的查詢，如果指定分片欄位ID欄位，則走分片查詢單個分片節點
mycat命令臺顯示結果：
mysql> explain select * from ORDER0402 t1 where t1.CREATE_TIME='2016-01-03';
+-----------+--------------------------------------------------------------------------+
| DATA_NODE | SQL |
+-----------+--------------------------------------------------------------------------+
| dn21 | SELECT * FROM ORDER0402 t1 WHERE t1.CREATE_TIME = '2016-01-03' LIMIT 100 |
+-----------+--------------------------------------------------------------------------+
1 row in set (0.04 sec)
mysql> select * from ORDER0402 t1 where t1.CREATE_TIME='2016-01-03';
+-------+----------+--------------------------+---------------------+
| ID | PROVINCE | SN | CREATE_TIME |
+-------+----------+--------------------------+---------------------+
| 10001 | shanghai | shanghai10006_2016-01-03 | 2016-01-03 00:00:00 |
+-------+----------+--------------------------+---------------------+
1 row in set (0.00 sec)
mysql> 檢視後臺mycat日誌資訊：
02/12 22:44:13.773 DEBUG [$_NIOREACTOR-2-RW] (ServerQueryHandler.java:56) -ServerConnection [id=1, schema=TESTDB, host=127.0.0.1, user=test,txIsolation=3, autocommit=true, schema=TESTDB]explain select * from ORDER0402 t1 where t1.CREATE_TIME='2016-01-03'
02/12 22:44:13.774 DEBUG [$_NIOREACTOR-2-RW] (EnchachePool.java:76) -SQLRouteCache miss cache ,key:TESTDB select * from ORDER0402 t1 where t1.CREATE_TIME='2016-01-03'
02/12 22:44:13.812 DEBUG [$_NIOREACTOR-2-RW] (EnchachePool.java:59) -SQLRouteCache add cache ,key:TESTDB select * from ORDER0402 t1 where t1.CREATE_TIME='2016-01-03' value:select * from ORDER0402 t1 where t1.CREATE_TIME='2016-01-03', route={
1 -> dn21{SELECT *
FROM ORDER0402 t1
WHERE t1.CREATE_TIME = '2016-01-03'
LIMIT 100}
}6，如果分片欄位範圍的查詢，則走所有節點去檢索，哪怕只有一條資料在一個分片上，route路由也是走所有的分片進行檢索查詢
mysql> explain select * from ORDER0402 t1 where t1.CREATE_TIME<'2016-01-04';
+-----------+--------------------------------------------------------------------------+
| DATA_NODE | SQL |
+-----------+--------------------------------------------------------------------------+
| dn21 | SELECT * FROM ORDER0402 t1 WHERE t1.CREATE_TIME < '2016-01-04' LIMIT 100 |
| dn22 | SELECT * FROM ORDER0402 t1 WHERE t1.CREATE_TIME < '2016-01-04' LIMIT 100 |
+-----------+--------------------------------------------------------------------------+
2 rows in set (0.01 sec)
mysql> 7，如果不走分片欄位的查詢，即使是單個數據，也要route路由所有的分片，走所有的分片進行查詢
mysql> explain select * from ORDER0402 t1 where t1.SN='shanghai10006_2016-01-03';
+-----------+-------------------------------------------------------------------------------+
| DATA_NODE | SQL |
+-----------+-------------------------------------------------------------------------------+
| dn21 | SELECT * FROM ORDER0402 t1 WHERE t1.SN = 'shanghai10006_2016-01-03' LIMIT 100 |
| dn22 | SELECT * FROM ORDER0402 t1 WHERE t1.SN = 'shanghai10006_2016-01-03' LIMIT 100 |
+-----------+-------------------------------------------------------------------------------+
2 rows in set (0.01 sec)
mysql>