Key Metrics to Monitor Query execution time (use EXPLAIN ANALYZE and slow query log) System resource utilization (CPU, memory, disk I/O) Monitoring memory usage is a critical metric in managing MySQL database performance. High memory usage can lead to slow query performance due to increased rel...
-- mysql8.0.11之前的版本 update user set authentication_string=password('新密码') where user='用户名'; 例: update user set authentication_string=password('123') where user='laowang'; --mysql8.0.11之后的版本 alter user '用户名'@'主机' IDENTIFIED WITH MYSQL_NATIVE_PASSWORD BY '你要修改的...
Hi guys. I've read the foreign key topic on the manual but it says nothing if foreign keys optimize the queries with INNER JOIN on the foreign key. I've read that indexes in general speed it up, but is it valid too for foreign index? I am often linking a medium sized table to ...
Hi Mr. Dinh, We created 51 tables, all of them in foreign key hierarchy. These are the results: MySQL 5.7: Empty set (0.03 sec) MySQL 8.0 Empty set (0.00 sec) MySQL 8.3 Empty set (0.01 sec) Hence, this bug report is not repeatable. ...
net start mysql 第二招、登陆mysql 语法如下: mysql -u用户名 -p用户密码 键入命令mysql -uroot -p, 回车后提示你输入密码,输入12345,然后回车即可进入到mysql中了,mysql的提示符是: mysql> 注意,如果是连接到另外的机器上,则需要加入一个参数-h机器IP ...
是mysql 启动时像os申请的一块空间 存储数据、change buffer、redolog show status like "%Innodb_...
trx_foreign_key_checks: 1 trx_last_foreign_key_error: NULL trx_adaptive_hash_latched: 0 trx_adaptive_hash_timeout: 0 trx_is_read_only: 0 trx_autocommit_non_locking: 0 trx_schedule_weight: NULL 1 row in set (0.00 sec) 其中trx_mysql_thread_id 是线程 id ,结合 information_schema.proces...
原因是我本地的数据库版本是8,服务的版本是5,所以出现了兼容问题,解决如下 把utf8mb4_0900_ai_ci 改为 utf8mb4_unicode_ci SET NAMES utf8mb4; SET FOREIGN_KEY_CHECKS = 0; -- --- -- Table structure for t_block -- --- DROP TABLE IF EXISTS `t_block...
SELECT/*+ SET_VAR(sort_buffer_size = 16M)*/nameFROMpeopleORDERBYname;INSERT/*+ SET_VAR(foreign_key_checks=OFF)*/INTOt2VALUES(2);SELECT/*+ SET_VAR(optimizer_switch = 'mrr_cost_based=off')*/1; Syntax of the SET_VAR hint:
PRIMARY KEY(Add_ID), INDEX(Add_ID), FOREIGN KEY(Add_ID) REFERENCES contacts (Add_ID) ) TYPE = INNODB; CREATE TABLE Phone ( Phone_ID int(10), Home int(8), Mobile int(8), Office int(8), PRIMARY KEY(Phone_ID), INDEX(Phone_ID), ...