Posted by MySQL, MySQLi, and PDO (PHP Data Objects) are all MySql PHP extensions that provide different interfaces for connecting to and interacting with a MySQL database.
Here is a brief overview of the main differences between MySQL, MySQLi, and PDO:
MySQL Extension:
The MySQL extension is a legacy extension that is no longer actively maintained by the PHP team. It provides a set of functions for connecting to and interacting with a MySQL database, such as
mysql_connect()
and
mysql_query()
.
However, this extension is vulnerable to security risks such as SQL injection attacks, and it does not support prepared statements or object-oriented programming. Because of these issues, it is not recommended to use this extension for new projects.
MySQLi (MySQL Improved) Extension:
The MySQLi (MySQL Improved) extension was developed as a replacement for the MySQL extension, with the goal of addressing some of the security and feature gaps present in the MySQL extension.
It provides a set of functions for connecting to and interacting with a MySQL database, such as
mysqli_connect()
and
mysqli_query()
. In addition to these functions, it also provides a set of object-oriented methods for working with databases, such as
mysqli->query()
and
mysqli->prepare()
.
MySQLi also supports prepared statements, which can help prevent SQL injection attacks by separating the data being passed to the database from the SQL query itself.
PDO Extension:
The PDO (PHP Data Objects) extension is a more modern extension that provides a database-agnostic interface for interacting with databases. This means that you can use the same set of functions and methods to connect to and query a variety of different database systems, including MySQL, Oracle, and SQLite.
PDO supports both object-oriented and procedural programming styles, and it provides a set of functions for working with prepared statements, such as
PDO->prepare()
and
PDOStatement->execute()
.
Overall, PDO is considered the best choice for connecting to a database in PHP due to its flexibility and security. It is more modern and feature-rich than the MySQL and MySQLi extensions, and it provides a consistent interface for working with multiple database systems.
However, if you are working with an existing codebase that uses MySQL or MySQLi, you may need to continue using those extensions.