When working with a large table, table partitioning divides the table into several subsets of data based on the given criteria and helps the database system to process one partition instead of scanning the whole table. That helps with the performance matter. In MySQL, there are four partitioning...
ident_or_text语义组用于解析标识符、任意未保留关键字、单引号 / 双引号字符串或用户自定义变量,详见MySQL 源码|41 - 语法解析(V2):标识符 IDENT; real_ulong_num语义组用于解析十进制整数和十六进制数(转换为十进制数),返回 unsigned long 类型;如果输入十进制小数或超出范围的十进制整数,则抛出异常,详见MySQL...
4.8 不支持spatial column types。 4.9 临时表不能被分区。 mysql>CREATETemporaryTABLE t1->( idINTNOTNULL,-> uidINTNOTNULL,->PRIMARY KEY(id)->)-> PARTITION BY RANGE(id)->(PARTITION p0VALUES LESS THAN(5)ENGINE= MyISAM,-> PARTITION p1VALUES LESS THAN(10)ENGINE= MyISAM->); ERROR1562(HY00...
(Partitioned tables created with the key-hashing functions employed in MySQL 5.5 and later cannot be used by a MySQL 5.1 server.) Not specifying the option has the same effect as using ALGORITHM=2. This option is intended for use chiefly when upgrading or downgrading [LINEAR] KEY partitioned...
Note In MySQL 5.7, all partitions of a partitioned table must have the same number of subpartitions, and it is not possible to change the subpartitioning once the table has been created. To change a table's partitioning scheme, it is necessary only to use theALTER TABLEstatement with apar...
学习MySQL Partition分区方法 参考文档:http://dev.mysql.com/doc/refman/5.1/en/partitioning-types.html Range分区,List分区,Hash分区,Key分区,各自区别见下面的create table语句就能一目了然。 AI检测代码解析 CREATE TABLE employees ( id INT NOT NULL,...
可以写partitions (分区数目),或直接使用分区语句,比如partition p0 values in…..。Key分区:与hash分区类似,只不过分区支持一列或多列,并且MySQL服务器自身提供hash函数。具体描述:分区语法:create table t(id int,name varchar(20)) engine=myisam partition by range(id);按range范围进行分区:create table ...
3 rows in set (0.10 sec) NULL 值分区 Doris 支持分区表中存储 NULL 值。对于自动分区功能而言,List 分区表的 NULL 值将会存储在真正的 NULL 分区中,例如: mysql> CREATE TABLE list_nullable -> ( -> `str` varchar NULL -> ) -> AUTO PARTITION BY LIST (`str`) ...
运行 AI代码解释 mysql> show partitions fromexample_db.example_range_tbl3\G; *** 1. row *** PartitionId 14489 PartitionName: p_20170103 VisibleVersion 1 VisibleVersionTime: 2023-02-08 16:54:18 State: PartitionKey: date Range: [types: DATE]; keys: [2017-01-03]; ..types: [DATE...
So far, we have looked only at examples using RANGE partitioning, but pruning can be applied with other partitioning types as well. Consider a table that is partitioned by LIST, where the partitioning expression is increasing or decreasing, such as the table t3 shown here. (In this example...