>mysqladmin -u root status>mysqladmin -help>mysqladmin -u root ping>mysqladmin -u root processlist>mysqladmin -u root refresh-------------------------------------------------------mysqladmin 适合于linux和windows系统linux下:mysqladmin -u[username] -p[password] status
windows下:先在安装目录找到mysqladmin.exe,然后在dos界面下change到这个目录,执行
mysqladmin -u[username] -p[password] extended-status
这里的extended-status 和status只是mysqladmin的两个参数而已!MySQLAdmin用法
用于执行管理性操作。语法是:
shell> mysqladmin [OPTIONS] command [command-option] command ...
通过执行mysqladmin --help,你可以得到你mysqladmin的版本所支持的一个选项列表。
目前mysqladmin支持下列命令:
create databasename 创建一个新数据库
drop databasename 删除一个数据库及其所有表
extended-status 给出服务器的一个扩展状态消息
flush-hosts 洗掉所有缓存的主机
flush-logs 洗掉所有日志
flush-tables 洗掉所有表
flush-privileges 再次装载授权表(同reload)
kill id,id,... 杀死mysql线程
password 新口令,将老口令改为新口令
ping 检查mysqld是否活着
processlist 显示服务其中活跃线程列表
reload 重载授权表
refresh 洗掉所有表并关闭和打开日志文件
shutdown 关掉服务器
status 给出服务器的简短状态消息
variables 打印出可用变量
version 得到服务器的版本信息
所有命令可以被缩短为其唯一的前缀。例如:
shell> mysqladmin proc stat
+----+-------+-----------+----+-------------+------+-------+------+
| Id | User | Host | db | Command | Time | State | Info |
+----+-------+-----------+----+-------------+------+-------+------+
| 6 | monty | localhost | | Processlist | 0 | | |
+----+-------+-----------+----+-------------+------+-------+------+
Uptime: 10077 Threads: 1 Questions: 9 Slow queries: 0 Opens: 6 Flush tables: 1
Open tables: 2 Memory in use: 1092K Max memory used: 1116K
mysqladmin status命令结果有下述列:
Uptime MySQL服务器已经运行的秒数
Threads 活跃线程(客户)的数量
Questions 从mysqld启动起来自客户问题的数量
Slow queries 已经超过long_query_time秒的查询数量
Opens mysqld已经打开了多少表
Flush tables flush ..., refresh和reload命令数量
Open tables 现在被打开的表数量
Memory in use 由mysqld代码直接分配的内存(只有在MySQL用--with-debug编译时可用)
Max memory used 由mysqld代码直接分配的最大内存(只有在MySQL用--with-debug编译时可用)

MySQL's position in databases and programming is very important. It is an open source relational database management system that is widely used in various application scenarios. 1) MySQL provides efficient data storage, organization and retrieval functions, supporting Web, mobile and enterprise-level systems. 2) It uses a client-server architecture, supports multiple storage engines and index optimization. 3) Basic usages include creating tables and inserting data, and advanced usages involve multi-table JOINs and complex queries. 4) Frequently asked questions such as SQL syntax errors and performance issues can be debugged through the EXPLAIN command and slow query log. 5) Performance optimization methods include rational use of indexes, optimized query and use of caches. Best practices include using transactions and PreparedStatemen

MySQL is suitable for small and large enterprises. 1) Small businesses can use MySQL for basic data management, such as storing customer information. 2) Large enterprises can use MySQL to process massive data and complex business logic to optimize query performance and transaction processing.

InnoDB effectively prevents phantom reading through Next-KeyLocking mechanism. 1) Next-KeyLocking combines row lock and gap lock to lock records and their gaps to prevent new records from being inserted. 2) In practical applications, by optimizing query and adjusting isolation levels, lock competition can be reduced and concurrency performance can be improved.

MySQL is not a programming language, but its query language SQL has the characteristics of a programming language: 1. SQL supports conditional judgment, loops and variable operations; 2. Through stored procedures, triggers and functions, users can perform complex logical operations in the database.

MySQL is an open source relational database management system, mainly used to store and retrieve data quickly and reliably. Its working principle includes client requests, query resolution, execution of queries and return results. Examples of usage include creating tables, inserting and querying data, and advanced features such as JOIN operations. Common errors involve SQL syntax, data types, and permissions, and optimization suggestions include the use of indexes, optimized queries, and partitioning of tables.

MySQL is an open source relational database management system suitable for data storage, management, query and security. 1. It supports a variety of operating systems and is widely used in Web applications and other fields. 2. Through the client-server architecture and different storage engines, MySQL processes data efficiently. 3. Basic usage includes creating databases and tables, inserting, querying and updating data. 4. Advanced usage involves complex queries and stored procedures. 5. Common errors can be debugged through the EXPLAIN statement. 6. Performance optimization includes the rational use of indexes and optimized query statements.

MySQL is chosen for its performance, reliability, ease of use, and community support. 1.MySQL provides efficient data storage and retrieval functions, supporting multiple data types and advanced query operations. 2. Adopt client-server architecture and multiple storage engines to support transaction and query optimization. 3. Easy to use, supports a variety of operating systems and programming languages. 4. Have strong community support and provide rich resources and solutions.

InnoDB's lock mechanisms include shared locks, exclusive locks, intention locks, record locks, gap locks and next key locks. 1. Shared lock allows transactions to read data without preventing other transactions from reading. 2. Exclusive lock prevents other transactions from reading and modifying data. 3. Intention lock optimizes lock efficiency. 4. Record lock lock index record. 5. Gap lock locks index recording gap. 6. The next key lock is a combination of record lock and gap lock to ensure data consistency.


Hot AI Tools

Undresser.AI Undress
AI-powered app for creating realistic nude photos

AI Clothes Remover
Online AI tool for removing clothes from photos.

Undress AI Tool
Undress images for free

Clothoff.io
AI clothes remover

AI Hentai Generator
Generate AI Hentai for free.

Hot Article

Hot Tools

Atom editor mac version download
The most popular open source editor

SAP NetWeaver Server Adapter for Eclipse
Integrate Eclipse with SAP NetWeaver application server.

PhpStorm Mac version
The latest (2018.2.1) professional PHP integrated development tool

Dreamweaver CS6
Visual web development tools

mPDF
mPDF is a PHP library that can generate PDF files from UTF-8 encoded HTML. The original author, Ian Back, wrote mPDF to output PDF files "on the fly" from his website and handle different languages. It is slower than original scripts like HTML2FPDF and produces larger files when using Unicode fonts, but supports CSS styles etc. and has a lot of enhancements. Supports almost all languages, including RTL (Arabic and Hebrew) and CJK (Chinese, Japanese and Korean). Supports nested block-level elements (such as P, DIV),