MySQL中怎么实现表分区功能
创始人
2024-12-21 17:21:58
0次

 MySQL表分区功能基础
  创建分区表
  CREATE TABLE `表名` (
  `EQUIPMENTID` char(17) NOT NULL,
  `ATTRIBUTEID` char(4) NOT NULL,
  `VALUE` varchar(20) NOT NULL,
  `COLLECTTIME` datetime NOT NULL
  )
  ENGINE=InnoDB (适用大部分引擎,可根据需要调整)
  DEFAULT CHARSET=gbk(编码可根据需要修改)
  PARTITION BY RANGE (to_days(COLLECTTIME))
  (PARTITION pmin VALUES LESS THAN (to_days('2010-01-01')),
  PARTITION p201001 VALUES LESS THAN (to_days('2010-02-01')) ,
  PARTITION p201002 VALUES LESS THAN (to_days('2010-03-01')) ,
  PARTITION p201003 VALUES LESS THAN (to_days('2010-04-01')) ,
  PARTITION p201004 VALUES LESS THAN (to_days('2010-05-01')) ,
  PARTITION p201005 VALUES LESS THAN (to_days('2010-06-01')) ,
  PARTITION p201006 VALUES LESS THAN (to_days('2010-07-01')) ,
  PARTITION p201007 VALUES LESS THAN (to_days('2010-08-01')) ,
  PARTITION p201008 VALUES LESS THAN (to_days('2010-09-01')) ,
  PARTITION p201009 VALUES LESS THAN (to_days('2010-10-01')) ,
  PARTITION p201010 VALUES LESS THAN (to_days('2010-11-01')),
  PARTITION p201011 VALUES LESS THAN (to_days('2010-12-01')),
  PARTITION p201012 VALUES LESS THAN (to_days('2011-01-01')),
  PARTITION p201101 VALUES LESS THAN (to_days('2011-02-01')),
  PARTITION p201102 VALUES LESS THAN (to_days('2011-03-01')),
  PARTITION p201103 VALUES LESS THAN (to_days('2011-04-01')),
  PARTITION p201104 VALUES LESS THAN (to_days('2011-05-01')),
  PARTITION p201105 VALUES LESS THAN (to_days('2011-06-01')),
  PARTITION p201106 VALUES LESS THAN (to_days('2011-07-01')),
  PARTITION p201107 VALUES LESS THAN (to_days('2011-08-01')),
  PARTITION p201108 VALUES LESS THAN (to_days('2011-09-01')),
  PARTITION p201109 VALUES LESS THAN (to_days('2011-10-01')),
  PARTITION p201110 VALUES LESS THAN (to_days('2011-11-01')),
  PARTITION p201111 VALUES LESS THAN (to_days('2011-12-01')),
  PARTITION p201112 VALUES LESS THAN (to_days('2012-01-01')),
  PARTITION pmax VALUES LESS THAN MAXVALUE );
  为现有表创建分区
  alter table 表名
  PARTITION BY RANGE (to_days(COLLECTTIME))
  (PARTITION pmin VALUES LESS THAN (to_days('2010-01-01')),
  PARTITION p201001 VALUES LESS THAN (to_days('2010-02-01')) ,
  PARTITION p201002 VALUES LESS THAN (to_days('2010-03-01')) ,
  PARTITION p201003 VALUES LESS THAN (to_days('2010-04-01')) ,
  PARTITION p201004 VALUES LESS THAN (to_days('2010-05-01')) ,
  PARTITION p201005 VALUES LESS THAN (to_days('2010-06-01')) ,
  PARTITION p201006 VALUES LESS THAN (to_days('2010-07-01')) ,
  PARTITION p201007 VALUES LESS THAN (to_days('2010-08-01')) ,
  PARTITION p201008 VALUES LESS THAN (to_days('2010-09-01')) ,
  PARTITION p201009 VALUES LESS THAN (to_days('2010-10-01')) ,
  PARTITION p201010 VALUES LESS THAN (to_days('2010-11-01')),
  PARTITION p201011 VALUES LESS THAN (to_days('2010-12-01')),
  PARTITION p201012 VALUES LESS THAN (to_days('2011-01-01')),
  PARTITION p201101 VALUES LESS THAN (to_days('2011-02-01')),
  PARTITION p201102 VALUES LESS THAN (to_days('2011-03-01')),
  PARTITION p201103 VALUES LESS THAN (to_days('2011-04-01')),
  PARTITION p201104 VALUES LESS THAN (to_days('2011-05-01')),
  PARTITION p201105 VALUES LESS THAN (to_days('2011-06-01')),
  PARTITION p201106 VALUES LESS THAN (to_days('2011-07-01')),
  PARTITION p201107 VALUES LESS THAN (to_days('2011-08-01')),
  PARTITION p201108 VALUES LESS THAN (to_days('2011-09-01')),
  PARTITION p201109 VALUES LESS THAN (to_days('2011-10-01')),
  PARTITION p201110 VALUES LESS THAN (to_days('2011-11-01')),
  PARTITION p201111 VALUES LESS THAN (to_days('2011-12-01')),
  PARTITION p201112 VALUES LESS THAN (to_days('2012-01-01')),
  PARTITION pmax VALUES LESS THAN MAXVALUE );
  如果表中已有数据,分区时会自动进行分区存储,不必担心数据丢失或者手动分类数据.
  删除表中的指定分区
  ALTER TABLE 表名 DROP PARTITION 分区名;
  追加表分区
  ALTER TABLE 表名 DROP PARTITION pmax;
  ALTER TABLE 表名
  ADD PARTITION (
  PARTITION p201201 VALUES LESS THAN (to_days('2012-2-1')),
  PARTITION pmax VALUES LESS THAN MAXVALUE);
  查看标分区信息
  SELECT
  partition_name part,
  partition_expression expr,
  partition_description descr,
  table_rows
  FROM
  INFORMATION_SCHEMA.partitions
  WHERE
  TABLE_SCHEMA = schema()
  AND TABLE_NAME='表名';
  查看查询语句涉及分区信息
  explain partitions
  select … from 表名 where …;
  该操作只查看查询语句相关的分区信息,不会返回查询结果.

相关内容

热门资讯

空调连续工作多久需要停机休息 空调连续工作的时间取决于多个因素,包括空调的型号、功率、使用环境和维护情况等。一般来说,空调可以连续...
空调哪个符号是除湿的 空调除湿功能通常用一个水滴形状的符号表示。不同品牌和型号的空调遥控器可能会有所差异,但一般来说,除湿...
格力空调多长时间加一次氟利昂 1、一般情况下,空调对氟利昂的使用量是非常小的,所以在空调使用了四年左右的时候再考虑加也没问题。2、...
空调用多长时间需要加氟一次 一般情况下是五年。当出现以下这几种情况时,空调才需要加氟。1、空调的室内机和室外机各有两个接口,当接...
格调生活·C标思享荟:卡萨帝在... 9月12日的郑州龙湖金融岛,夜风轻拂,灯光璀璨。“C标时刻共传奇——卡萨帝思享荟暨20周年品牌盛典郑...
品牌价值破千亿、高端份额持续领... 9月12日,“C标时刻共传奇——卡萨帝思享荟暨20周年品牌盛典郑州站”在郑州龙湖金融岛举办。2026...
空调主板坏了修800还是换新的 空调主板坏了是修还是换新,需要考虑多个因素,以下是一些建议:1. 维修成本:如果维修费用较低,比如 ...
空调开多久需要休息多长时间 问题:空调开多久需要休息多长时间回答:1、在使用空调的过程中,一般空调开7~8个小时左右需要休息2~...
中央空调多长时间清洗一次 1、一般空调开机前清洗一次即可,空调开机中间时段再清洗一次,空调关机时清洗一次,这样比较合理。2、空...
中央空调氟利昂多久加一次 看空调制热和制冷程度,很多人的观点认为氟利昂必须一年放一次,其实这个观点是错误的,理解上面有点偏差,...