MySQL分区管理
以下是我看MySQL官方文檔的時候整理的筆記，僅作參考保留。 RANGE,LIST分區管理 1:為未分區表創建分區 ALTER TABLE trb3 PARTITION BY KEY(id) PARTITIONS 2; 2:刪除某個分區的數據 ALTER TABLE tr DROP PARTITION p2;
3:為分區表添加一個分區
ALTER TABLE members ADD PARTITION (PARTITION p3 VALUES LESS THAN (2000)); ALTER TABLE tt ADD PARTITION (PARTITION p2 VALUES IN (7, 14, 21)); ALTER TABLE employees ADD PARTITION (PARTITION p5 VALUES LESS THAN (2010),PARTITION p6 VALUES LESS THAN MAXVALUE );4:將分區表的第一個分區分為兩個新的分區
ALTER TABLE membersREORGANIZE PARTITION p0 INTO (PARTITION n0 VALUES LESS THAN (1960),PARTITION n1 VALUES LESS THAN (1970) );5:也可以將兩個分區合并為一個分區,也可以理解為重新組織分區
ALTER TABLE members REORGANIZE PARTITION s0,s1 INTO (PARTITION p0 VALUES LESS THAN (1970) ); ALTER TABLE tbl_nameREORGANIZE PARTITION partition_listINTO (partition_definitions); ALTER TABLE members REORGANIZE PARTITION p0,p1,p2,p3 INTO (PARTITION m0 VALUES LESS THAN (1980),PARTITION m1 VALUES LESS THAN (2000) ); ALTER TABLE tt ADD PARTITION (PARTITION np VALUES IN (4, 8)); ALTER TABLE tt REORGANIZE PARTITION p1,np INTO (PARTITION p1 VALUES IN (6, 18),PARTITION np VALUES in (4, 8, 12) );HASH,KEY?分區管理
1:創建一個hash分區表 CREATE TABLE clients (id INT,fname VARCHAR(30),lname VARCHAR(30),signed DATE ) PARTITION BY HASH( MONTH(signed) ) PARTITIONS 12;將分區表從12個分區變為8個分區
ALTER TABLE clients COALESCE PARTITION 4;同樣的有以下的語句關于KEY分區的表:
mysql> CREATE TABLE clients_lk (-> id INT,-> fname VARCHAR(30),-> lname VARCHAR(30),-> signed DATE-> )-> PARTITION BY LINEAR KEY(signed)-> PARTITIONS 12; Query OK, 0 rows affected (0.03 sec)mysql> ALTER TABLE clients_lk COALESCE PARTITION 4; Query OK, 0 rows affected (0.06 sec) Records: 0 Duplicates: 0 Warnings: 0當然還有有限制的
mysql> ALTER TABLE clients COALESCE PARTITION 18; ERROR 1478 (HY000): Cannot remove all partitions, use DROP TABLE instead要是分區數比現有的分區數多的話,只能使用 ADD來添加分區數.下面就表示增加了6個分區數
ALTER TABLE clients ADD PARTITION PARTITIONS 6;交換分區,子分區的管理
交換分區,ALTER TABLE?pt?EXCHANGE PARTITION?p?WITH TABLE?nt
where?pt?is the partitioned table and?p?is the partition or subpartition of?pt?to be exchanged with unpartitioned table?nt, provided that the following statements are true: 要滿足以下的條件: 1:PT是已經分區表,nt不是臨時表 2:兩張表的表結構必須是一模一樣的 3:nt不能有外鍵約束,也不能有關于其他表的外鍵約束. 4:nt表中的數據沒有分區P以外的數據.WITHOUT VALIDATION指定的時候這條就可以忽視調 另外很重要的一點就是想要擁有EXCHANGE的權限的話必須對全表有DROP的權限才可以執行. alter table ?......EXCHANGE partition ?將不會調用任何的觸發器,執行完以后被EXCHANGE 的表的自增列就會重新賦初始值. 例如: ALTER TABLE pt EXCHANGE PARTITION p WITH TABLE nt with VALIDATION ;1:將分區和一個沒有分區的表EXCHANGE
創建表插入語句: CREATE TABLE e (id INT NOT NULL,fname VARCHAR(30),lname VARCHAR(30) )PARTITION BY RANGE (id) (PARTITION p0 VALUES LESS THAN (50),PARTITION p1 VALUES LESS THAN (100),PARTITION p2 VALUES LESS THAN (150),PARTITION p3 VALUES LESS THAN (MAXVALUE) );INSERT INTO e VALUES (1669, "Jim", "Smith"),(337, "Mary", "Jones"),(16, "Frank", "White"),(2005, "Linda", "Black");查看分區和分區的行數
SELECT PARTITION_NAME, TABLE_ROWS FROM INFORMATION_SCHEMA.PARTITIONS WHERE TABLE_NAME = 'e';SELECT TABLE_NAME, PARTITION_NAME, TABLE_ROWS, AVG_ROW_LENGTH, DATA_LENGTH FROM INFORMATION_SCHEMA.PARTITIONS WHERE TABLE_SCHEMA = 'p' AND TABLE_NAME LIKE 'e';創建新表:
CREATE TABLE e2 LIKE e;然后交換分區開始了:
ALTER TABLE e EXCHANGE PARTITION p0 WITH TABLE e2;這個語句是很奇怪的,如果e2里面沒有數據的話就是切出分區,如果e2里面有數據的話就是相互交換
但是如果e2里面的數據不能夠滿足分區p0的要求的話,切分區就會失敗. 1737?-?Found?a?row?that?does?not?match?the?partition 只有再指定不驗證的時候才不會報錯 ALTER TABLE e EXCHANGE PARTITION p0 WITH TABLE e2 WITHOUT VALIDATION;WITHOUT VALIDATION?指定的時候效率會更高,因為不再做逐行驗證了.
子分區和沒分區的表進行切換
1:假設創建一個分區表,帶有子分區 > CREATE TABLE es (-> id INT NOT NULL,-> fname VARCHAR(30),-> lname VARCHAR(30)-> )-> PARTITION BY RANGE (id)-> SUBPARTITION BY KEY (lname)-> SUBPARTITIONS 2 (-> PARTITION p0 VALUES LESS THAN (50),-> PARTITION p1 VALUES LESS THAN (100),-> PARTITION p2 VALUES LESS THAN (150),-> PARTITION p3 VALUES LESS THAN (MAXVALUE)-> );然后就可以切分區了,先查看一下分區,
SELECT PARTITION_NAME, SUBPARTITION_NAME, TABLE_ROWSFROM INFORMATION_SCHEMA.PARTITIONSWHERE TABLE_NAME = 'es';然后切出分區:
ALTER TABLE es EXCHANGE PARTITION p3sp0 WITH TABLE es2;當前執行切出分區前,必須要對新表做以下的處理:
ALTER TABLE es2 REMOVE PARTITIONING;修改表的默認引擎:
ALTER TABLE es3 ENGINE = MyISAM;維護表分區
1:重建分區 ALTER TABLE t1 REBUILD PARTITION p0, p1;2:重新組織分區
ALTER TABLE t1 OPTIMIZE PARTITION p0, p1;3:分析某個分區,主要看行數和名稱以及狀態
ALTER TABLE t1 ANALYZE PARTITION p3;4:修復分區,有重復值的時候就會報錯.
ALTER TABLE t1 REPAIR PARTITION p0,p1;5:檢查分區的狀態
ALTER TABLE trb3 CHECK PARTITION p1;6:truncate分區?
ALTER TABLE ... TRUNCATE PARTITION. ALTER TABLE ... TRUNCATE PARTITION ALL7:獲取表的信息
Using the?SHOW CREATE TABLE?statement to view the partitioning clauses used in creating a partitioned table.
Using the?SHOW TABLE STATUS?statement to determine whether a table is partitioned.
Querying the?INFORMATION_SCHEMA.PARTITIONS?table.
Using the statement?EXPLAIN PARTITIONS SELECT?to see which partitions are used by a given?SELECT.
看以下信息: mysql> EXPLAIN PARTITIONS SELECT * FROM trb1\G *************************** 1. row ***************************id: 1select_type: SIMPLEtable: trb1partitions: p0,p1,p2,p3type: ALL possible_keys: NULLkey: NULLkey_len: NULLref: NULLrows: 10Extra: Using filesort分區的經典案例:
mysql> CREATE TABLE employees_sub (-> id INT NOT NULL AUTO_INCREMENT,-> fname VARCHAR(25) NOT NULL,-> lname VARCHAR(25) NOT NULL,-> store_id INT NOT NULL,-> department_id INT NOT NULL,-> PRIMARY KEY pk (id, lname)-> ) -> PARTITION BY RANGE(id)-> SUBPARTITION BY KEY (lname)-> SUBPARTITIONS 2 (-> PARTITION p0 VALUES LESS THAN (5),-> PARTITION p1 VALUES LESS THAN (10),-> PARTITION p2 VALUES LESS THAN (15),-> PARTITION p3 VALUES LESS THAN MAXVALUE-> );分區的一些添刪查修語句:
mysql> DELETE FROM employees PARTITION (p0, p1) -> WHERE fname LIKE 'j%'; Query OK, 2 rows affected (0.09 sec) mysql> UPDATE employees PARTITION (p2)-> SET store_id = 2 WHERE fname = 'Jill'; SELECT * FROM employees PARTITION (p2); mysql> INSERT INTO employees PARTITION (p2) VALUES (20, 'Jan', 'Jones', 1, 3);ERROR 1729 (HY000): Found a row not matching the given partition set mysql> INSERT INTO employees PARTITION (p3) VALUES (20, 'Jan', 'Jones', 1, 3); Query OK, 1 row affected (0.07 sec)分區不夠多,要添加分區:
ysql> ALTER TABLE employees-> REORGANIZE PARTITION p3 INTO (-> PARTITION p3 VALUES LESS THAN (20),-> PARTITION p4 VALUES LESS THAN (25),-> PARTITION p5 VALUES LESS THAN MAXVALUE-> ); Query OK, 6 rows affected (2.09 sec) Records: 6 Duplicates: 0 Warnings: 0 RANGE,LIST分區管理 1:為未分區表創建分區 ALTER TABLE trb3 PARTITION BY KEY(id) PARTITIONS 2;2:刪除某個分區的數據
ALTER TABLE tr DROP PARTITION p2;3:為分區表添加一個分區
ALTER TABLE members ADD PARTITION (PARTITION p3 VALUES LESS THAN (2000)); ALTER TABLE tt ADD PARTITION (PARTITION p2 VALUES IN (7, 14, 21)); ALTER TABLE employees ADD PARTITION (PARTITION p5 VALUES LESS THAN (2010),PARTITION p6 VALUES LESS THAN MAXVALUE );4:將分區表的第一個分區分為兩個新的分區
ALTER TABLE membersREORGANIZE PARTITION p0 INTO (PARTITION n0 VALUES LESS THAN (1960),PARTITION n1 VALUES LESS THAN (1970) );5:也可以將兩個分區合并為一個分區,也可以理解為重新組織分區
ALTER TABLE members REORGANIZE PARTITION s0,s1 INTO (PARTITION p0 VALUES LESS THAN (1970) ); ALTER TABLE tbl_nameREORGANIZE PARTITION partition_listINTO (partition_definitions); ALTER TABLE members REORGANIZE PARTITION p0,p1,p2,p3 INTO (PARTITION m0 VALUES LESS THAN (1980),PARTITION m1 VALUES LESS THAN (2000) ); ALTER TABLE tt ADD PARTITION (PARTITION np VALUES IN (4, 8)); ALTER TABLE tt REORGANIZE PARTITION p1,np INTO (PARTITION p1 VALUES IN (6, 18),PARTITION np VALUES in (4, 8, 12) );HASH,KEY?分區管理
1:創建一個hash分區表 CREATE TABLE clients (id INT,fname VARCHAR(30),lname VARCHAR(30),signed DATE ) PARTITION BY HASH( MONTH(signed) ) PARTITIONS 12;將分區表從12個分區變為8個分區
ALTER TABLE clients COALESCE PARTITION 4;同樣的有以下的語句關于KEY分區的表:
mysql> CREATE TABLE clients_lk (-> id INT,-> fname VARCHAR(30),-> lname VARCHAR(30),-> signed DATE-> )-> PARTITION BY LINEAR KEY(signed)-> PARTITIONS 12; Query OK, 0 rows affected (0.03 sec)mysql> ALTER TABLE clients_lk COALESCE PARTITION 4; Query OK, 0 rows affected (0.06 sec) Records: 0 Duplicates: 0 Warnings: 0當然還有有限制的
mysql> ALTER TABLE clients COALESCE PARTITION 18; ERROR 1478 (HY000): Cannot remove all partitions, use DROP TABLE instead要是分區數比現有的分區數多的話,只能使用 ADD來添加分區數.下面就表示增加了6個分區數
ALTER TABLE clients ADD PARTITION PARTITIONS 6;交換分區,子分區的管理
交換分區, ALTER TABLE pt EXCHANGE PARTITION p WITH TABLE ntwhere?pt?is the partitioned table and?p?is the partition or subpartition of?pt?to be exchanged with unpartitioned table?nt, provided that the following statements are true:
要滿足以下的條件: 1:PT是已經分區表,nt不是臨時表 2:兩張表的表結構必須是一模一樣的 3:nt不能有外鍵約束,也不能有關于其他表的外鍵約束. 4:nt表中的數據沒有分區P以外的數據.WITHOUT VALIDATION指定的時候這條就可以忽視調 另外很重要的一點就是想要擁有EXCHANGE的權限的話必須對全表有DROP的權限才可以執行. alter table ?......EXCHANGE partition ?將不會調用任何的觸發器,執行完以后被EXCHANGE 的表的自增列就會重新賦初始值. 例如: ALTER TABLE pt EXCHANGE PARTITION p WITH TABLE nt with VALIDATION ;1:將分區和一個沒有分區的表EXCHANGE
創建表插入語句: CREATE TABLE e (id INT NOT NULL,fname VARCHAR(30),lname VARCHAR(30) )PARTITION BY RANGE (id) (PARTITION p0 VALUES LESS THAN (50),PARTITION p1 VALUES LESS THAN (100),PARTITION p2 VALUES LESS THAN (150),PARTITION p3 VALUES LESS THAN (MAXVALUE) );INSERT INTO e VALUES (1669, "Jim", "Smith"),(337, "Mary", "Jones"),(16, "Frank", "White"),(2005, "Linda", "Black");查看分區和分區的行數?
SELECT PARTITION_NAME, TABLE_ROWS FROM INFORMATION_SCHEMA.PARTITIONS WHERE TABLE_NAME = 'e'; SELECT TABLE_NAME, PARTITION_NAME, TABLE_ROWS, AVG_ROW_LENGTH, DATA_LENGTH FROM INFORMATION_SCHEMA.PARTITIONS WHERE TABLE_SCHEMA = 'p' AND TABLE_NAME LIKE 'e';?
創建新表: CREATE TABLE e2 LIKE e;然后交換分區開始了:
ALTER TABLE e EXCHANGE PARTITION p0 WITH TABLE e2;這個語句是很奇怪的,如果e2里面沒有數據的話就是切出分區,如果e2里面有數據的話就是相互交換
但是如果e2里面的數據不能夠滿足分區p0的要求的話,切分區就會失敗. 1737?-?Found?a?row?that?does?not?match?the?partition 只有再指定不驗證的時候才不會報錯 ALTER TABLE e EXCHANGE PARTITION p0 WITH TABLE e2 WITHOUT VALIDATION;WITHOUT VALIDATION?指定的時候效率會更高,因為不再做逐行驗證了.
子分區和沒分區的表進行切換 1:假設創建一個分區表,帶有子分區 > CREATE TABLE es (-> id INT NOT NULL,-> fname VARCHAR(30),-> lname VARCHAR(30)-> )-> PARTITION BY RANGE (id)-> SUBPARTITION BY KEY (lname)-> SUBPARTITIONS 2 (-> PARTITION p0 VALUES LESS THAN (50),-> PARTITION p1 VALUES LESS THAN (100),-> PARTITION p2 VALUES LESS THAN (150),-> PARTITION p3 VALUES LESS THAN (MAXVALUE)-> );然后就可以切分區了,先查看一下分區,
SELECT PARTITION_NAME, SUBPARTITION_NAME, TABLE_ROWSFROM INFORMATION_SCHEMA.PARTITIONSWHERE TABLE_NAME = 'es';然后切出分區:
ALTER TABLE es EXCHANGE PARTITION p3sp0 WITH TABLE es2;當前執行切出分區前,必須要對新表做以下的處理:
ALTER TABLE es2 REMOVE PARTITIONING;修改表的默認引擎:
ALTER TABLE es3 ENGINE = MyISAM;維護表分區
1:重建分區 ALTER TABLE t1 REBUILD PARTITION p0, p1;2:重新組織分區
ALTER TABLE t1 OPTIMIZE PARTITION p0, p1;3:分析某個分區,主要看行數和名稱以及狀態
ALTER TABLE t1 ANALYZE PARTITION p3;4:修復分區,有重復值的時候就會報錯.
ALTER TABLE t1 REPAIR PARTITION p0,p1;5:檢查分區的狀態
ALTER TABLE trb3 CHECK PARTITION p1;6:truncate分區
ALTER TABLE ... TRUNCATE PARTITION. ALTER TABLE ... TRUNCATE PARTITION ALL?
7:獲取表的信息Using the?SHOW CREATE TABLE?statement to view the partitioning clauses used in creating a partitioned table.
Using the?SHOW TABLE STATUS?statement to determine whether a table is partitioned.
Querying the?INFORMATION_SCHEMA.PARTITIONS?table.
Using the statement?EXPLAIN PARTITIONS SELECT?to see which partitions are used by a given?SELECT.
看以下信息: mysql> EXPLAIN PARTITIONS SELECT * FROM trb1\G *************************** 1. row ***************************id: 1select_type: SIMPLEtable: trb1partitions: p0,p1,p2,p3type: ALL possible_keys: NULLkey: NULLkey_len: NULLref: NULLrows: 10Extra: Using filesort?
分區的經典案例: mysql> CREATE TABLE employees_sub (-> id INT NOT NULL AUTO_INCREMENT,-> fname VARCHAR(25) NOT NULL,-> lname VARCHAR(25) NOT NULL,-> store_id INT NOT NULL,-> department_id INT NOT NULL,-> PRIMARY KEY pk (id, lname)-> ) -> PARTITION BY RANGE(id)-> SUBPARTITION BY KEY (lname)-> SUBPARTITIONS 2 (-> PARTITION p0 VALUES LESS THAN (5),-> PARTITION p1 VALUES LESS THAN (10),-> PARTITION p2 VALUES LESS THAN (15),-> PARTITION p3 VALUES LESS THAN MAXVALUE-> );分區的一些添刪查修語句:
mysql> DELETE FROM employees PARTITION (p0, p1) -> WHERE fname LIKE 'j%'; Query OK, 2 rows affected (0.09 sec) mysql> UPDATE employees PARTITION (p2)-> SET store_id = 2 WHERE fname = 'Jill'; SELECT * FROM employees PARTITION (p2); mysql> INSERT INTO employees PARTITION (p2) VALUES (20, 'Jan', 'Jones', 1, 3);ERROR 1729 (HY000): Found a row not matching the given partition set mysql> INSERT INTO employees PARTITION (p3) VALUES (20, 'Jan', 'Jones', 1, 3); Query OK, 1 row affected (0.07 sec)分區不夠多,要添加分區:
ysql> ALTER TABLE employees-> REORGANIZE PARTITION p3 INTO (-> PARTITION p3 VALUES LESS THAN (20),-> PARTITION p4 VALUES LESS THAN (25),-> PARTITION p5 VALUES LESS THAN MAXVALUE-> ); Query OK, 6 rows affected (2.09 sec) Records: 6 Duplicates: 0 Warnings: 0?最后歡迎加入技術交流群：291519319
轉載于:https://www.cnblogs.com/shengdimaya/p/5384884.html
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