How to delete database connection in php code

With the continuous development of Internet technology, PHP, as a very popular programming language, is widely used in website development. In the process of developing PHP programs, connecting to the database is a very important process. However, not handling database connections properly can lead to slow program performance, security risks, and high server loads. Therefore, when writing PHP code, it is very necessary to delete useless database connections.

In this article, we will explore how to delete a database connection in PHP code and why this is very important.

Why do you need to delete useless database connections?

Database connection is one of the very common methods used in PHP programs. As we know, data in the database can be manipulated and managed by connecting to the database. Because this operation involves network connections and processing large amounts of data, it requires a lot of server resources and time. Therefore, retaining useless database connections will lead to the following problems:

1. Excessive service load: If the server does not have enough resources, connecting too many databases will cause resources to be exhausted quickly, thereby reducing the service quality.
2. The database is vulnerable to attack: Undeleted database connections not only waste server resources, but may also be used by bad actors to attack the server.
3. Program runs slowly: Leaving unused database connections will increase the running time of the program, especially when large amounts of data are processed simultaneously, which requires establishing and disconnecting a large number of database connections in a short period of time.

How to delete useless database connections?

When writing PHP code, it is very important to delete useless database connections, which can be achieved in the following ways:

Close the connection

After communicating with the database, You should always remember to close the connection. This can be achieved by adding the mysqli_close() function at the end of the script code:

mysqli_close($conn);

Using long connections

"Long connection" means that in a A persistent connection between an application and the database during application execution. During this connection, the application can execute one or more selected SQL statements without reconnecting. Therefore, using long connections can avoid multiple database connections in a short period of time and improve the running speed of the program.

Using connection pool

The connection pool is a set of predefined connections that can be reused during database operations. Using a connection pool can avoid establishing and disconnecting a large number of database connections over a period of time, thereby greatly reducing database connection overhead and server load.

Reduce connection time

Unless it is necessary to connect to the database, the frequency of connection and disconnection should be reduced as much as possible. This can be achieved by using caching technology to execute multiple SQL statements within a single connection.

Use the database connection pool to give APC

APC (Alternative PHP Cache) is a cache extension for PHP that can greatly improve the performance of PHP programs. Connection pooling is a caching technology used in databases. Combining these two technologies can optimize the way database connections are used and greatly improve the performance of PHP programs.

Summary

When writing PHP code, it is very necessary to delete useless database connections. It can reduce the waste of server resources, improve program performance, and enhance server security. The above are several common methods for deleting database connections. These methods can help you better manage and optimize database connections in PHP programs.

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