What is SQL Injection and How to Prevent it in PHP?

SQL injection is a common web security vulnerability that allows attackers to execute malicious SQL queries through input fields of a web form or URL parameters.

Prevention Techniques in PHP:

Prepared Statements:

• Use prepared statements with parameterized queries instead of directly embedding user input into SQL queries.
• Prepared statements separate SQL logic from data, preventing attackers from injecting malicious SQL code.

Parameterized Queries:

• Bind user input to SQL placeholders.
• Prevents alteration of SQL structure or injection of malicious commands.

Input Validation and Sanitization:

• Validate and sanitize user input.
• Utilize PHP functions or regex to remove malicious characters.

Database User Privileges:

• Restrict database user privileges.
• Grant only necessary permissions, avoiding excessive access.

Error Handling and Logging:

• Implement error handling for unexpected input or database errors.
• Log SQL errors and suspicious activities for monitoring.

Security Best Practices:

• Stay updated on security practices.
• Regularly update frameworks and libraries.
• Conduct security assessments and penetration testing.