


PHP Warning: mysqli_connect(): (HY000/2002): Solution to Connection refused
If you encounter the following error message when using PHP to connect to a MySQL database:
PHP Warning: mysqli_connect(): (HY000/2002): Connection refused
Then you can try the following steps to resolve this issue.
- Confirm whether the MySQL service is running normally
First you should check whether the MySQL service is running normally. If the service is not running or fails to start, it may cause a connection refused error. . You can check the status of the MySQL service by using the following command:
$ systemctl status mysql.service
If the MySQL service is not running, you can use the following command to start the service:
$ systemctl start mysql.service
- Check whether the MySQL service is listening on the correct port
If the MySQL service is already running, you need to check whether the MySQL service is listening on the correct port. By default, the MySQL service listening port is 3306. You can check the port bound by the MySQL service through the following command:
$ netstat -an | grep 3306
If the MySQL service is not bound to the correct port, you need to configure it in the MySQL configuration file ( my.cnf), add the following lines:
[mysqld]
port=3306
After modifying the configuration file, you need to restart the MySQL service for the modification to take effect:
$ systemctl restart mysql.service
- Confirm that the username and password are correct
If the MySQL service is running correctly and listening on the correct port, you need to check the user Are the name and password correct? When connecting to MySQL, you need to use the correct username and password to log in to the MySQL server. If you are not sure whether the username and password are correct, you can try to log in using this username and password in the MySQL command line interface:
$ mysql -u username -p
In this command, You need to replace "username" with the username you want to use, and then enter this user's password to log in to the MySQL server. If the login is successful, it means that the username and password you entered are correct.
- Confirm whether the MySQL database permissions are correct
The last step is to confirm whether the user connecting to MySQL has sufficient permissions to access the database that needs to be used. When connecting to the MySQL server, you need to specify the name of the database to connect to. If the specified database does not exist or you do not have permission to access the database, the connection will be refused.
You can check the permissions of the MySQL user through the following command:
$ mysql -u username -p -e "SHOW GRANTS FOR username;"
In this In the command, you need to replace "username" with the MySQL user whose permissions you want to query. After executing this command, you can see the permissions this user has.
If the database you want to access does not exist or does not have access permissions, you need to use the following command in the MySQL command line interface to create or grant access permissions:
CREATE DATABASE dbname;
GRANT ALL PRIVILEGES ON dbname.* TO 'username'@'localhost';
In this command, you need to replace "dbname" with the name of the database you want to create, and "username" with the database name you want to authorize MySQL username.
Summary
Through the above steps, you should be able to solve the PHP Warning: mysqli_connect(): (HY000/2002): Connection refused error. First, you need to check whether the MySQL service has been started and is listening on the correct port; second, you need to confirm whether the user name and password entered are correct; finally, you need to check whether the MySQL user has permission to access the database.
The above is the detailed content of PHP Warning: mysqli_connect(): (HY000/2002): Solution to Connection refused. For more information, please follow other related articles on the PHP Chinese website!

What’s still popular is the ease of use, flexibility and a strong ecosystem. 1) Ease of use and simple syntax make it the first choice for beginners. 2) Closely integrated with web development, excellent interaction with HTTP requests and database. 3) The huge ecosystem provides a wealth of tools and libraries. 4) Active community and open source nature adapts them to new needs and technology trends.

PHP and Python are both high-level programming languages that are widely used in web development, data processing and automation tasks. 1.PHP is often used to build dynamic websites and content management systems, while Python is often used to build web frameworks and data science. 2.PHP uses echo to output content, Python uses print. 3. Both support object-oriented programming, but the syntax and keywords are different. 4. PHP supports weak type conversion, while Python is more stringent. 5. PHP performance optimization includes using OPcache and asynchronous programming, while Python uses cProfile and asynchronous programming.

PHP is mainly procedural programming, but also supports object-oriented programming (OOP); Python supports a variety of paradigms, including OOP, functional and procedural programming. PHP is suitable for web development, and Python is suitable for a variety of applications such as data analysis and machine learning.

PHP originated in 1994 and was developed by RasmusLerdorf. It was originally used to track website visitors and gradually evolved into a server-side scripting language and was widely used in web development. Python was developed by Guidovan Rossum in the late 1980s and was first released in 1991. It emphasizes code readability and simplicity, and is suitable for scientific computing, data analysis and other fields.

PHP is suitable for web development and rapid prototyping, and Python is suitable for data science and machine learning. 1.PHP is used for dynamic web development, with simple syntax and suitable for rapid development. 2. Python has concise syntax, is suitable for multiple fields, and has a strong library ecosystem.

PHP remains important in the modernization process because it supports a large number of websites and applications and adapts to development needs through frameworks. 1.PHP7 improves performance and introduces new features. 2. Modern frameworks such as Laravel, Symfony and CodeIgniter simplify development and improve code quality. 3. Performance optimization and best practices further improve application efficiency.

PHPhassignificantlyimpactedwebdevelopmentandextendsbeyondit.1)ItpowersmajorplatformslikeWordPressandexcelsindatabaseinteractions.2)PHP'sadaptabilityallowsittoscaleforlargeapplicationsusingframeworkslikeLaravel.3)Beyondweb,PHPisusedincommand-linescrip

PHP type prompts to improve code quality and readability. 1) Scalar type tips: Since PHP7.0, basic data types are allowed to be specified in function parameters, such as int, float, etc. 2) Return type prompt: Ensure the consistency of the function return value type. 3) Union type prompt: Since PHP8.0, multiple types are allowed to be specified in function parameters or return values. 4) Nullable type prompt: Allows to include null values and handle functions that may return null values.


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

Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Article

Hot Tools

SublimeText3 English version
Recommended: Win version, supports code prompts!

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),

SublimeText3 Mac version
God-level code editing software (SublimeText3)

MinGW - Minimalist GNU for Windows
This project is in the process of being migrated to osdn.net/projects/mingw, you can continue to follow us there. MinGW: A native Windows port of the GNU Compiler Collection (GCC), freely distributable import libraries and header files for building native Windows applications; includes extensions to the MSVC runtime to support C99 functionality. All MinGW software can run on 64-bit Windows platforms.

Atom editor mac version download
The most popular open source editor