本文介紹如何使用不同的拆分方式進行分庫分表：
以下示例均假設已經建好的分庫數爲 8。
使用哈希函數做拆分
建一張表，既分庫又分表，每個庫含有 3 張物理表，分庫拆分方式爲按照 id 列進行哈希，分表拆分方式爲按照 bid 列進行哈希（先根據 id 列的值進行哈希運算，將表中數據分佈在多個子庫中，每個子庫中的數據再根據 bid 列值的哈希運算結果分佈在3個物理表中）。
CREATE TABLE multi_db_multi_tbl(id int auto_increment,bid int,name varchar(30),primary key(id)) dbpartition by hash(id) tbpartition by hash(bid) tbpartitions 3;
查看該邏輯表的節點拓撲，可以看出在每個分庫都創建了 3 張分表。
mysql> show topology from multi_db_multi_tbl;+------+------------------------------------------------------------------+-----------------------+| ID | GROUP_NAME | TABLE_NAME |+------+------------------------------------------------------------------+-----------------------+| 0 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | multi_db_multi_tbl_00 || 1 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | multi_db_multi_tbl_01 || 2 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | multi_db_multi_tbl_02 || 3 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0001_RDS | multi_db_multi_tbl_03 || 4 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0001_RDS | multi_db_multi_tbl_04 || 5 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0001_RDS | multi_db_multi_tbl_05 || 6 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0002_RDS | multi_db_multi_tbl_06 || 7 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0002_RDS | multi_db_multi_tbl_07 || 8 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0002_RDS | multi_db_multi_tbl_08 || 9 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0003_RDS | multi_db_multi_tbl_09 || 10 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0003_RDS | multi_db_multi_tbl_10 || 11 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0003_RDS | multi_db_multi_tbl_11 || 12 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0004_RDS | multi_db_multi_tbl_12 || 13 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0004_RDS | multi_db_multi_tbl_13 || 14 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0004_RDS | multi_db_multi_tbl_14 || 15 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0005_RDS | multi_db_multi_tbl_15 || 16 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0005_RDS | multi_db_multi_tbl_16 || 17 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0005_RDS | multi_db_multi_tbl_17 || 18 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0006_RDS | multi_db_multi_tbl_18 || 19 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0006_RDS | multi_db_multi_tbl_19 || 20 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0006_RDS | multi_db_multi_tbl_20 || 21 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | multi_db_multi_tbl_21 || 22 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | multi_db_multi_tbl_22 || 23 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | multi_db_multi_tbl_23 |+------+------------------------------------------------------------------+-----------------------+24 rows in set (0.01 sec)
查看該邏輯表的拆分規則，可以看出分庫分表的拆分拆分方式均爲哈希，分庫的拆分鍵爲 id，分表的拆分鍵爲 bid。
mysql> show rule from multi_db_multi_tbl;+------+--------------------+-----------+------------------+---------------------+--------------------+------------------+---------------------+--------------------+| ID | TABLE_NAME | BROADCAST | DB_PARTITION_KEY | DB_PARTITION_POLICY | DB_PARTITION_COUNT | TB_PARTITION_KEY | TB_PARTITION_POLICY | TB_PARTITION_COUNT |+------+--------------------+-----------+------------------+---------------------+--------------------+------------------+---------------------+--------------------+| 0 | multi_db_multi_tbl | 0 | id | hash | 8 | bid | hash | 3 |+------+--------------------+-----------+------------------+---------------------+--------------------+------------------+---------------------+--------------------+1 row in set (0.01 sec)
使用雙字段哈希函數做拆分
使用要求
拆分鍵的類型必須是字符類型或數字類型。
路由方式
根據任一拆分鍵後 N 位計算哈希值，以哈希方式完成路由計算。N 爲函數第三個參數。例如：RANGE_HASH(COL1, COL2, N)，計算時會優先選擇 COL1 ，截取其後 N 位進行計算。 COL1 不存在時按 COL2 計算。
適用場景
適合於需要有兩個拆分鍵，並且僅使用其中一個拆分鍵值進行查詢時的場景。例如，假設用戶的 DRDS 裏已經分了 8 個物理庫, 現業務有如下的場景：
- 一個業務想按買家 ID 和訂單 ID 對訂單表進行分庫；
- 查詢時條件僅有買家 ID 或訂單 ID。
此時可使用以下 DDL 對訂單表進行構建：
create table test_order_tb (id int,seller_id varchar(30) DEFAULT NULL,order_id varchar(30) DEFAULT NULL,buyer_id varchar(30) DEFAULT NULL,create_time datetime DEFAULT NULL,primary key(id)) ENGINE=InnoDB DEFAULT CHARSET=utf8 dbpartition by RANGE_HASH(buyer_id, order_id, 10) tbpartition by RANGE_HASH(buyer_id, order_id, 10) tbpartitions 3;
注意事項
- 兩個拆分鍵皆不能修改。
- 插入數據時如果發現兩個拆分鍵指向不同的分庫或分表時，插入會失敗。
使用日期做拆分
除了可以使用哈希函數做拆分算法，您還可以使用日期函數 MM/DD/WEEK/MMDD 來作爲分表的拆分算法，具體參照以下五個示例：
建一張表，既分庫又分表，分庫方式爲根據 userId 列哈希，分表方式爲根據 actionDate 列，按照一週七天來拆分（
WEEK(actionDate)計算的是DAY_OF_WEEK）。比如 actionDate 列的值是 2017-02-27，這天是星期一，
WEEK(actionDate)算出的值是2，該條記錄就會被存儲到 2（2 % 7 = 2）這張分表（位於某個分庫，具體的表名是user_log_2）；比如 actionDate 列的值是 2017-02-26，這天是星期天，WEEK(actionDate)算出的值是1，該條記錄就會被存儲到 1（1 % 7 = 1）這張分表（位於某個分庫，具體的表名是user_log_1）。CREATE TABLE user_log(userId int,name varchar(30),operation varchar(30),actionDate DATE) dbpartition by hash(userId) tbpartition by WEEK(actionDate) tbpartitions 7;
查看該邏輯表的節點拓撲，可以看出在每個分庫都創建了 7 張分表（一週7天）。以下示例中返回的結果較長，用…做了省略處理。
mysql> show topology from user_log;+------+------------------------------------------------------------------+------------+| ID | GROUP_NAME | TABLE_NAME |+------+------------------------------------------------------------------+------------+| 0 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | user_log_0 || 1 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | user_log_1 || 2 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | user_log_2 || 3 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | user_log_3 || 4 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | user_log_4 || 5 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | user_log_5 || 6 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | user_log_6 || 7 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0001_RDS | user_log_0 || 8 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0001_RDS | user_log_1 || 9 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0001_RDS | user_log_2 || 10 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0001_RDS | user_log_3 || 11 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0001_RDS | user_log_4 || 12 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0001_RDS | user_log_5 || 13 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0001_RDS | user_log_6 |...| 49 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log_0 || 50 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log_1 || 51 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log_2 || 52 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log_3 || 53 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log_4 || 54 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log_5 || 55 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log_6 |+------+------------------------------------------------------------------+------------+56 rows in set (0.01 sec)
查看該邏輯表的拆分規則，可以看出分庫的拆分方式爲哈希，分庫的拆分鍵爲 userId，分表的拆分方式爲按照時間函數 WEEK 進行拆分，分表的拆分鍵爲 actionDate。
mysql> show rule from user_log;+------+------------+-----------+------------------+---------------------+--------------------+------------------+---------------------+--------------------+| ID | TABLE_NAME | BROADCAST | DB_PARTITION_KEY | DB_PARTITION_POLICY | DB_PARTITION_COUNT | TB_PARTITION_KEY | TB_PARTITION_POLICY | TB_PARTITION_COUNT |+------+------------+-----------+------------------+---------------------+--------------------+------------------+---------------------+--------------------+| 0 | user_log | 0 | userId | hash | 8 | actionDate | week | 7 |+------+------------+-----------+------------------+---------------------+--------------------+------------------+---------------------+--------------------+1 row in set (0.00 sec)
查看給定分庫鍵和分表鍵參數時， SQL 被路由到哪個物理分庫和該物理分庫下的哪張物理表。
![ddl_week_sharding]()
建一張表，既分庫又分表，分庫方式爲根據 userId 列哈希，分表方式爲根據 actionDate 列，按照一年 12 個月進行拆分（
MM(actionDate)計算的是MONTH_OF_YEAR）。比如 actionDate 列的值是 2017-02-27，
MM(actionDate)算出的值是02，該條記錄就會被存儲到02（02 % 12 = 02）這張分表（位於某個分庫，具體的表名是user_log_02）；比如 actionDate 列的值是 2016-12-27，MM(actionDate)算出的值是 12，該條記錄就會被存儲到00（12 % 12 = 00）這張分表（位於某個分庫，具體的表名是user_log_00）。CREATE TABLE user_log2(userId int,name varchar(30),operation varchar(30),actionDate DATE) dbpartition by hash(userId) tbpartition by MM(actionDate) tbpartitions 12;
查看該邏輯表的節點拓撲，可以看出在每個分庫都創建了 12 張分表（1 年有 12 個月）。由於返回結果較長，這裏用…做了省略處理。
mysql> show topology from user_log2;+------+------------------------------------------------------------------+--------------+| ID | GROUP_NAME | TABLE_NAME |+------+------------------------------------------------------------------+--------------+| 0 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | user_log2_00 || 1 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | user_log2_01 || 2 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | user_log2_02 || 3 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | user_log2_03 || 4 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | user_log2_04 || 5 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | user_log2_05 || 6 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | user_log2_06 || 7 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | user_log2_07 || 8 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | user_log2_08 || 9 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | user_log2_09 || 10 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | user_log2_10 || 11 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | user_log2_11 || 12 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0001_RDS | user_log2_00 || 13 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0001_RDS | user_log2_01 || 14 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0001_RDS | user_log2_02 || 15 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0001_RDS | user_log2_03 || 16 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0001_RDS | user_log2_04 || 17 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0001_RDS | user_log2_05 || 18 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0001_RDS | user_log2_06 || 19 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0001_RDS | user_log2_07 || 20 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0001_RDS | user_log2_08 || 21 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0001_RDS | user_log2_09 || 22 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0001_RDS | user_log2_10 || 23 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0001_RDS | user_log2_11 |...| 84 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log2_00 || 85 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log2_01 || 86 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log2_02 || 87 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log2_03 || 88 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log2_04 || 89 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log2_05 || 90 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log2_06 || 91 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log2_07 || 92 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log2_08 || 93 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log2_09 || 94 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log2_10 || 95 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log2_11 |+------+------------------------------------------------------------------+--------------+96 rows in set (0.02 sec)
查看該邏輯表的拆分規則，可以看出分庫的拆分方式爲哈希，分庫的拆分鍵爲 userId，分表的拆分方式爲按照時間函數 MM 進行拆分，分表的拆分鍵爲 actionDate。
mysql> show rule from user_log2;+------+------------+-----------+------------------+---------------------+--------------------+------------------+---------------------+--------------------+| ID | TABLE_NAME | BROADCAST | DB_PARTITION_KEY | DB_PARTITION_POLICY | DB_PARTITION_COUNT | TB_PARTITION_KEY | TB_PARTITION_POLICY | TB_PARTITION_COUNT |+------+------------+-----------+------------------+---------------------+--------------------+------------------+---------------------+--------------------+| 0 | user_log2 | 0 | userId | hash | 8 | actionDate | mm | 12 |+------+------------+-----------+------------------+---------------------+--------------------+------------------+---------------------+--------------------+1 row in set (0.00 sec)
建一張表，既分庫又分表，分庫方式爲根據 userId 列哈希，分表方式爲按照一個月 31 天進行拆分（函數
DD(actionDate)計算的是DAY_OF_MONTH）。比如 actionDate 列的值是 2017-02-27，
DD(actionDate)算出的值是 27，該條記錄就會被存儲到27（27 % 31 = 27）這張分表（位於某個分庫，具體的表名是user_log_27）。CREATE TABLE user_log3(userId int,name varchar(30),operation varchar(30),actionDate DATE) dbpartition by hash(userId) tbpartition by DD(actionDate) tbpartitions 31;
查看該邏輯表的節點拓撲，可以看出在每個分庫都創建了 31 張分表（按每個月有31天處理）。由於返回的結果較長，這裏用…做了省略處理。
mysql> show topology from user_log3;+------+------------------------------------------------------------------+--------------+| ID | GROUP_NAME | TABLE_NAME |+------+------------------------------------------------------------------+--------------+| 0 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | user_log3_00 || 1 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | user_log3_01 || 2 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | user_log3_02 || 3 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | user_log3_03 || 4 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | user_log3_04 || 5 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | user_log3_05 || 6 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | user_log3_06 || 7 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | user_log3_07 || 8 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | user_log3_08 || 9 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | user_log3_09 || 10 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | user_log3_10 || 11 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | user_log3_11 || 12 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | user_log3_12 || 13 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | user_log3_13 || 14 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | user_log3_14 || 15 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | user_log3_15 || 16 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | user_log3_16 || 17 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | user_log3_17 || 18 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | user_log3_18 || 19 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | user_log3_19 || 20 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | user_log3_20 || 21 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | user_log3_21 || 22 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | user_log3_22 || 23 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | user_log3_23 || 24 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | user_log3_24 || 25 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | user_log3_25 || 26 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | user_log3_26 || 27 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | user_log3_27 || 28 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | user_log3_28 || 29 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | user_log3_29 || 30 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | user_log3_30 |...| 237 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log3_20 || 238 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log3_21 || 239 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log3_22 || 240 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log3_23 || 241 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log3_24 || 242 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log3_25 || 243 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log3_26 || 244 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log3_27 || 245 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log3_28 || 246 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log3_29 || 247 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log3_30 |+------+------------------------------------------------------------------+--------------+248 rows in set (0.01 sec)
查看該邏輯表的拆分規則，可以看出分庫的拆分方式爲哈希，分庫的拆分鍵爲 userId，分表的拆分方式爲按照時間函數 DD 進行拆分，分表的拆分鍵爲 actionDate。
mysql> show rule from user_log3;+------+------------+-----------+------------------+---------------------+--------------------+------------------+---------------------+--------------------+| ID | TABLE_NAME | BROADCAST | DB_PARTITION_KEY | DB_PARTITION_POLICY | DB_PARTITION_COUNT | TB_PARTITION_KEY | TB_PARTITION_POLICY | TB_PARTITION_COUNT |+------+------------+-----------+------------------+---------------------+--------------------+------------------+---------------------+--------------------+| 0 | user_log3 | 0 | userId | hash | 8 | actionDate | dd | 31 |+------+------------+-----------+------------------+---------------------+--------------------+------------------+---------------------+--------------------+1 row in set (0.01 sec)
建一張表，既分庫又分表，分庫方式爲根據 userId 列哈希，分表方式爲按照一年 365 天進行拆分，路由到 365 張物理表（
MMDD(actionDate) tbpartitions 365計算的是DAY_OF_YEAR % 365）。比如 actionDate 列的值是 2017-02-27，
MMDD(actionDate)算出的值是 58，該條記錄就會被存儲到 58 這張分表（位於某個分庫，具體的表名是user_log_58）。CREATE TABLE user_log4(userId int,name varchar(30),operation varchar(30),actionDate DATE) dbpartition by hash(userId) tbpartition by MMDD(actionDate) tbpartitions 365;
查看該邏輯表的節點拓撲，可以看出在每個分庫都創建了 365 張分表（按每年有 365 天處理）。由於返回的結果較長，這裏用…做了省略處理。
mysql> show topology from user_log4;+------+------------------------------------------------------------------+---------------+| ID | GROUP_NAME | TABLE_NAME |+------+------------------------------------------------------------------+---------------+...| 2896 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log4_341 || 2897 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log4_342 || 2898 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log4_343 || 2899 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log4_344 || 2900 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log4_345 || 2901 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log4_346 || 2902 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log4_347 || 2903 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log4_348 || 2904 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log4_349 || 2905 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log4_350 || 2906 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log4_351 || 2907 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log4_352 || 2908 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log4_353 || 2909 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log4_354 || 2910 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log4_355 || 2911 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log4_356 || 2912 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log4_357 || 2913 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log4_358 || 2914 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log4_359 || 2915 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log4_360 || 2916 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log4_361 || 2917 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log4_362 || 2918 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log4_363 || 2919 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log4_364 |+------+------------------------------------------------------------------+---------------+2920 rows in set (0.07 sec)
查看該邏輯表的拆分規則，可以看出分庫的拆分方式爲哈希，分庫的拆分鍵爲 userId，分表的拆分方式爲按照時間函數 MMDD 進行拆分，分表的拆分鍵爲 actionDate。
mysql> show rule from user_log4;+------+------------+-----------+------------------+---------------------+--------------------+------------------+---------------------+--------------------+| ID | TABLE_NAME | BROADCAST | DB_PARTITION_KEY | DB_PARTITION_POLICY | DB_PARTITION_COUNT | TB_PARTITION_KEY | TB_PARTITION_POLICY | TB_PARTITION_COUNT |+------+------------+-----------+------------------+---------------------+--------------------+------------------+---------------------+--------------------+| 0 | user_log4 | 0 | userId | hash | 8 | actionDate | mmdd | 365 |+------+------------+-----------+------------------+---------------------+--------------------+------------------+---------------------+--------------------+1 row in set (0.02 sec)
建一張表，既分庫又分表，分庫方式爲根據 userId 列哈希，分表方式爲按照一年 365 天進行拆分，路由到 10 張物理表（
MMDD(actionDate) tbpartitions 10計算的是DAY_OF_YEAR % 10）。CREATE TABLE user_log5(userId int,name varchar(30),operation varchar(30),actionDate DATE) dbpartition by hash(userId) tbpartition by MMDD(actionDate) tbpartitions 10;
查看該邏輯表的節點拓撲，可以看出在每個分庫都創建了 10 張分表（按照一年 365 天進行拆分，路由到 10 張物理表）。由於返回的結果較長，這裏用…做了省略處理。
mysql> show topology from user_log5;+------+------------------------------------------------------------------+--------------+| ID | GROUP_NAME | TABLE_NAME |+------+------------------------------------------------------------------+--------------+| 0 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | user_log5_00 || 1 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | user_log5_01 || 2 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | user_log5_02 || 3 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | user_log5_03 || 4 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | user_log5_04 || 5 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | user_log5_05 || 6 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | user_log5_06 || 7 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | user_log5_07 || 8 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | user_log5_08 || 9 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0000_RDS | user_log5_09 |...| 70 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log5_00 || 71 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log5_01 || 72 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log5_02 || 73 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log5_03 || 74 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log5_04 || 75 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log5_05 || 76 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log5_06 || 77 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log5_07 || 78 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log5_08 || 79 | SANGUAN_TEST_123_1488766060743ACTJSANGUAN_TEST_123_WVVP_0007_RDS | user_log5_09 |+------+------------------------------------------------------------------+--------------+80 rows in set (0.02 sec)
查看該邏輯表的拆分規則，可以看出分庫的拆分方式爲哈希，分庫的拆分鍵爲 userId，分表的拆分方式爲按照時間函數 MMDD 進行拆分，路由到10張物理表，分表的拆分鍵爲 actionDate。
mysql> show rule from user_log5;+------+------------+-----------+------------------+---------------------+--------------------+------------------+---------------------+--------------------+| ID | TABLE_NAME | BROADCAST | DB_PARTITION_KEY | DB_PARTITION_POLICY | DB_PARTITION_COUNT | TB_PARTITION_KEY | TB_PARTITION_POLICY | TB_PARTITION_COUNT |+------+------------+-----------+------------------+---------------------+--------------------+------------------+---------------------+--------------------+| 0 | user_log5 | 0 | userId | hash | 8 | actionDate | mmdd | 10 |+------+------------+-----------+------------------+---------------------+--------------------+------------------+---------------------+--------------------+1 row in set (0.01 sec)
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