MySQL的默認(rèn)用戶名通常是'root',但密碼因安裝環(huán)境而異;在部分Linux發(fā)行版中,root賬戶可能通過auth_socket插件認(rèn)證,無法使用密碼登錄;Windows下的XAMPP或WAMP等工具安裝時(shí)root用戶通常無密碼或使用常見密碼如root、mysql等;若忘記密碼可通過停止MySQL服務(wù)、以--skip-grant-tables模式啟動(dòng)、更新mysql.user表設(shè)置新密碼並重啟服務(wù)的方式重置;注意MySQL 8.0 版本需額外處理認(rèn)證插件。
MySQL doesn't come with a single fixed default username and password that works everywhere — it depends on how and where you installed it. But there are some common defaults you should know, especially if you're setting up a local development environment or connecting to a fresh installation.
Default Username: Usually 'root'
In most standard MySQL installations (like those from Oracle's official installer, XAMPP, or Linux package managers), the default administrative user is 'root' . This is similar to the root user in Linux systems — it has full control over the database server.
But here's the catch:
- On some setups (especially Linux distributions like Ubuntu), the root account might be tied to the system login via
auth_socket
plugin, meaning you can't log in with a password from tools like phpMyAdmin or MySQL Workbench unless you change the authentication method. - In other cases (like WAMP or older versions of XAMPP), the root user often has no password by default .
Common Default Passwords
Here's what typically happens:
- In many Windows-based setups (like XAMPP or WAMP), the root user may have no password at all by default.
- Some installers will ask you to set a password during installation — if you did that, then obviously the default no longer applies.
- In certain Docker images or cloud environments, default credentials might be specified in documentation. For example, some containers use
root
as username andexample
orpassword
for testing purposes.
If you're unsure, try logging in without a password first:
mysql -u root
If that doesn't work, try entering it with an empty password or common ones like root
, mysql
, or admin
.
How to Reset or Find the MySQL Password
If you've lost your MySQL root password or never set one and can't remember what it is, you can reset it using these general steps:
- Stop the MySQL server process.
- Start it again in safe mode with privilege bypass:
mysqld --skip-grant-tables
- Connect to MySQL without a password:
mysql -u root
- Update the password for the root user:
UPDATE mysql.user SET authentication_string = PASSWORD('new_password') WHERE User = 'root'; FLUSH PRIVILEGES;
- Restart MySQL normally.
? Note: This is a simplified version. Exact commands may vary slightly depending on your MySQL version and OS.
Also, newer versions of MySQL (8.0 ) use different authentication plugins, so resetting passwords might require additional steps like switching to caching_sha2_password
or using ALTER USER
.
That's basically it — there's no universal default password for MySQL, but there are common defaults you can try based on your environment. If those don't work, resetting the password is usually the way to go. Just make sure you keep track of it once you set one.
以上是MySQL的默認(rèn)用戶名和密碼是什麼?的詳細(xì)內(nèi)容。更多資訊請關(guān)注PHP中文網(wǎng)其他相關(guān)文章!

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