MySQL partition table create delete modify view

Partition table creation

The primary key of the partitioned table / All unique keys must contain partition keys

--  Create range partition table 
CREATE TABLE `test_first` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `usr_id` varchar(32) COLLATE utf8_bin DEFAULT NULL COMMENT ' The user no. ',
	`remark` varchar(1024) COLLATE utf8_bin DEFAULT NULL COMMENT ' remarks ',
  `rec_upd_ts` datetime(6) DEFAULT CURRENT_TIMESTAMP(6) ON UPDATE CURRENT_TIMESTAMP(6) COMMENT ' Record update time ',
  `rec_crt_ts` datetime(6) DEFAULT CURRENT_TIMESTAMP(6) COMMENT ' Record creation time ',
  `get_date` date NOT NULL COMMENT ' Partition field , Equity acquisition date ',
  PRIMARY KEY (`id`,`get_date`)
) ENGINE=InnoDB AUTO_INCREMENT=15 DEFAULT CHARSET=utf8 COLLATE=utf8_bin COMMENT=' Test partition table '
/*!50500 PARTITION BY RANGE COLUMNS(get_date) (PARTITION p_2021 VALUES LESS THAN ('2022-1-1') , PARTITION p_2022 VALUES LESS THAN ('2023-1-1') , PARTITION p_2023 VALUES LESS THAN ('2024-1-1') , PARTITION p_2024 VALUES LESS THAN ('2025-1-1') , PARTITION p_2025 VALUES LESS THAN ('2026-1-1') , PARTITION p_2026 VALUES LESS THAN ('2027-1-1') , PARTITION p_2027 VALUES LESS THAN ('2028-1-1') , PARTITION p_2028 VALUES LESS THAN ('2029-1-1') , PARTITION p_2029 VALUES LESS THAN ('2030-1-1') , PARTITION p_2030 VALUES LESS THAN ('2031-1-1') , PARTITION p_2031 VALUES LESS THAN ('2032-1-1') , PARTITION p_catchall VALUES LESS THAN (MAXVALUE) ENGINE = InnoDB) */;

explain ：
Be careful ：range The corresponding partition creation value must be a value or a comparable size type ）.
range： The representative partition mode is range partition
less than： Say less than
Means less than a specific value , such as less than (2022-1-1), Then the value of the partition field is less than 2022-1-1 Of is in this partition , It doesn't contain 2022-1-1.
PARTITION p_catchall VALUES LESS THAN (MAXVALUE) ENGINE = InnoDB) Indicates that the rest of the range will fall to by default p_catchall Partition , Remove the statement if no default partition is required .

--  establish list Partition table 
CREATE TABLE `test_second` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `usr_id` varchar(32) COLLATE utf8_bin DEFAULT NULL COMMENT ' The user no. ',
	`remark` varchar(1024) COLLATE utf8_bin DEFAULT NULL COMMENT ' remarks ',
  `rec_upd_ts` datetime(6) DEFAULT CURRENT_TIMESTAMP(6) ON UPDATE CURRENT_TIMESTAMP(6) COMMENT ' Record update time ',
  `rec_crt_ts` datetime(6) DEFAULT CURRENT_TIMESTAMP(6) COMMENT ' Record creation time ',
	`type` char(2) COLLATE utf8_bin NOT NULL COMMENT ' type ',
  PRIMARY KEY (`id`,`type`)
) ENGINE=InnoDB AUTO_INCREMENT=15 DEFAULT CHARSET=utf8 COLLATE=utf8_bin COMMENT=' test list Partition table '
/*!50500 PARTITION BY LIST COLUMNS(type) (PARTITION p_1 values IN ('01','11') , PARTITION p_2 values IN ('02','12') , PARTITION p_3 values IN ('03','13') ) */;

explain ：
LIST: Represents that the partition mode is the given value partition
in : When expressed as a given value
When type The value is ‘01’,‘11’ Store at p_1 Partition

New zoning

--  New range partition 
alter TABLE `test_first` add PARTITION(
  PARTITION p_2032 VALUES LESS THAN ('2033-1-1') ENGINE = InnoDB
);

--  newly added list Partition 
alter TABLE `test_second` add PARTITION(
  PARTITION p_4 values IN ('04','14') ENGINE = InnoDB
);

explain ： Because partitions are incremented , If the default partition outside the range is executed when creating the partition , You cannot add a new partition , Because even without adding partitions , The data will also fall into the default partition . And if there is no default partition , The newly added partition should be added at the end

Delete partition

--  Delete the specified partition ( The data in the table will also be cleaned up )
alter table `test_first`  drop PARTITION p_2029 ;

--  Delete multiple partitions ( The data in the table will also be cleaned up )
alter table `test_first`  drop PARTITION p_2028,p_2029 ;

-- Delete all partitions of the table （ Delete only partitions , Do not delete data in the table ）
alter table test_first remove partitioning;

Check the partition

--  Check whether it is a partitioned table 
SHOW table STATUS;

--  View the partition information of the specified table 
 select 
  partition_name part,  
  partition_expression expr,  
  partition_description descr,  
  table_rows  
from information_schema.partitions  where 
  table_schema = schema()  
  and table_name='test_first';  

--  View the data in the specified partition 
SELECT * FROM test_first PARTITION(p_2022);