When using PHP for web development, operating databases is one of the most common tasks in daily work. In order to prevent security issues such as SQL injection, we need to perform appropriate escape processing on the data entered by the user. When using MySQL databases, PHP's mysqli extension provides a commonly used and secure function: real_escape_string, used to escape strings, thereby improving the security of database operations.
When using PHP to manipulate MySQL databases, the setting of the character set is crucial, especially in environments involving Chinese or other multibyte characters. mysqli::set_charset and mysqli_set_charset are two ways to set character sets provided by PHP. Although their functions are basically the same, there are certain differences in how they are used and applicable scenarios. This article will compare these two functions in detail and discuss their respective usage scenarios.
When connecting to a database using PHP's mysqli extension, you often see developers using the mysqli::set_charset method to set the character set. So, what does the character set set by mysqli::set_charset have a relationship with the default character set of the database itself? Will there be conflicts between them? This article will explain in detail the relationship between the two and best practices.
In PHP development, using mysqli to extend the operation of databases is a common and efficient way. Especially after we perform the insert operation, we usually use $mysqli->insert_id to get the auto-increment ID of the newly inserted record. However, although $insert_id itself does not cause SQL injection problems, it is still crucial to prevent SQL injection throughout the process of inserting data.
What is mysqli::character_set_name? mysqli::character_set_name is a method in PHP's mysqli extension that returns the character set name used by the current database connection. The prototype of this method is as follows:
Learn how to diagnose and resolve frequent connection-related issues when initiating transactions with mysqli::begin_transaction() in MySQL. This guide covers connectivity, permissions, engine compatibility, autocommit settings, error handling, network checks, and log analysis.
What is mysqli::$info? mysqli::$info is a read-only property that returns the detailed information generated by the recently executed query. It is usually used in UPDATE, DELETE, or INSERT ... ON DUPLICATE KEY UPDATE statement to provide information such as the number of affected rows, warnings, etc.
1. Introduction to mysqli_error() mysqli_error() is one of the most familiar error handling functions for developers. Its function is to return a string describing the error when the database operation fails. For example, when executing an incorrect SQL statement:
When using PHP for MySQL database operations, developers usually pay more attention to the query results themselves, such as the number of rows returned or whether the execution is successful, and it is easy to ignore a useful debugging tool - the mysqli::$info attribute. After some types of SQL statements are executed, this property can return more statistics about the execution results, helping us to understand the impact of a query more comprehensively.
1. The essential difference between PDO and mysqli connection errors: Connection and query errors are reported through the exception mechanism (PDOException). The code can be captured using try...catch, and the exception information contains detailed error descriptions.
The $connect_error property is an important debugging tool when using PHP's mysqli extension for database connections. When the connection to the database fails, it should return an error message. However, many developers find that when debugging database connection problems: mysqli::$connect_error returns one. This is confusing and is not conducive to the rapid positioning of the problem. This article will analyze in detail the reasons that may cause this phenomenon and provide corresponding solutions.
