How can you prevent SQL injection in PHP?

Using prepared statements with parameterized queries is a highly effective way to prevent SQL injection in PHP. This method involves preparing the SQL query in advance and then binding user input as parameters. When executed, the database knows how to differentiate between the SQL code and the data input, which helps to prevent malicious code from being executed. This separation of code and data ensures that any input provided by users does not alter the intended structure of the SQL query.

Prepared statements also provide an additional layer of security by allowing the database to compile the SQL statement once and execute it multiple times with different parameters, without needing to rebuild the SQL structure each time. This not only improves security but can also enhance performance.

While HTML escaping can protect against cross-site scripting (XSS) attacks, it does not address the issue of SQL injection. Disabling database errors merely hides potential errors but does not prevent them, and using the eval() function can introduce serious security vulnerabilities itself by executing arbitrary PHP code. Thus, the use of prepared statements is the most effective and recommended method to safeguard against SQL injection attacks.