change buffer(在MySQL5.6 之前叫 insert buffer,简称 ibuf )是 InnoDB 5.5 引入的一种优化策略,若二级索引页不在 buffer pool 中,则将针对二级索引页的操作暂时缓存起来,等到该页从磁盘读到 buffer pool 中时再批量的(batch)apply 这些操作,从而达到减少磁盘 I/O 的目的。具体一点就是: 事务1 执行写操作(e....
pt-online-schema-change 使用了MySQL内部变更表的方式,但是 是对 需要变更表的中间表(很多人也叫幽灵表) 使用MySQL内部变更的方式。这意味着原表不会被锁表,客户端可以继续对该表进行读写。 1、检查更改表是否有主键或唯一索引,是否有触发器 2、检查修改表的表结构,创建一个中间表,在中间表上执行ALTER TABLE...
如上,可根据生成的data做进一步处理,有较大的自由度,而此处我需要的是直接插入到另一台主机上的同样的库表中,因此我需要将data再解析为sql语句: def data_to_sql(data: dict) -> str: db = data['db'] table = data['db'] sql = '' # insert if data['event_type'] == 1: dic_data = data...
CREATE DATABASE IF NOT EXISTS partition_test; USE partition_test; -- 测试表1:主键不包含分区字段 CREATE TABLE sales_data ( id INT AUTO_INCREMENT, product_id INT NOT NULL, sale_date DATE NOT NULL, amount DECIMAL(10,2) NOT NULL, region VARCHAR(50), -- 原始主键不包含分区字段 PRIMARY KEY...
change buffer(在 MySQL 5.6 之前叫 insert buffer,简称 ibuf )是 InnoDB 5.5 引入的一种优化策略,若二级索引页不在buffer pool 中,则将针对二级索引页的操作暂时缓存起来,等到该页从磁盘读到 buffer pool 中时再批量的(batch)apply 这些操作,从而达到减少磁盘 I/O 的目的。具体一点就是: 事务1 执行写操作(...
VALUES('Learn MySQL CREATE TABLE', Now(), Now(), 'Practicing MySQL CREATE TABLE statement');And you can query data to see if the value of the task_id column is increased by 1 each time you insert a new row:1 2 3 4 SELECT task_id, description FROM tasks;Using...
The IP address configured with this option, if any, can be seen in theSource_Bindcolumn of the output fromSHOW REPLICA STATUS. In the source metadata repository tablemysql.slave_master_info, the value can be seen as theSource_bindcolumn. The ability to bind a replica to a specific network...
lock. Try LOCK=SHARED. mysql-5.6.24> ALTERTABLE t1 MODIFYCOLUMN `foo` char(11) CHARACTER SET ascii DEFAULT NULL, LOCK=NONE, ALGORITHM=INPLACE; ERROR 1846 (0A000): ALGORITHM=INPLACE is not supported. Reason: Cannot change column typeINPLACE. Try ALGORITHM=COPY. mysql-5.6.24 ALTER...
change process [--sequential-restart] old_proc_type[:proc-id]=new_proc_type cluster_name old_proc_type | new_proc_type: {ndbd|ndbmtd} This command is used to change the process type for a given MySQL NDB Cluster process or group of MySQL NDB Cluster processes from one process type (...
type back in a compound ALTER TABLE statement, like this: alter table t1 convert to character set utf8, modify t text;How to repeat:create table t1 (t text) character set latin1; show create table t1\G alter table t1 convert to character set utf8; show create table t1\G mysql> ...