Here are some interview questions for LAMP developers, hope these will helpful for you.


  • What is the difference between php4 and php5 ?
  • Difference between session and cookiee.
  • What is recursion ?
  • What are magic functions ?
  • What is register_global ?
  • What do you mean by headers ?
  • Any idea about buffering ?
  • String related functions ?
  • Difference between htmlentities() and htmlspecialchars().
  • What are the technique you have used for protect your site by hacking ?
  • What is DOMDOCUMENT ?
  • Array functions and date functions.
  • Image functions like getimagesize().
  • Payment gateways and curl process.
  • Environment variables.
  • Session management via database.
  • Model View Controller(MVC) Architecture.
  • implode() and explode() functions.
  • Regular expression.
  • What is ffmpeg/mencoder library ?
  • serialize() and unserialize() array function.
  • Types of errors in PHP.
  • Difference between var_dump() and print_r() function.
  • Difference between passbyvalue and passbyreference.
  • What are the smarty modifiers (If worked in smarty) ?
  • How can you check weather the extention is installed or not in php ?
  • What is the difference between $var_name and $$var_name ?
  • What is difference between require_once(), require(), include() ?
  • How can you change the value of php.ini directives ?
  • What is the default Memory size in php and how can you update that ?
  • Difference between copy() and move_uploaded_file() function.
  • How to find 3rd highest salary using a single query ?


  • Concepts of class and object.
  • Difference between abstract class and interface.
  • Why you have used interfaces/ use of interface ?
  • What is the use of static function ?
  • What is the difference between overloading and overriding ?
  • What is encapsulation ?
  • What is the benefits of OOP over procedure based coding ?
  • Is multiple inheritance possible in PHP ?
  • Explain something about Access modifiers.
  • Difference between extends and implements ?
  • Final/Const keywords.

Payment Gateway related

  • What is the difference between paypal standard and paypal pro ?
  • What is paypal IPN ?
  • What are the basic html fields of paypal standard ?
  • Have you ever integrated recurring payment using papal ?
  • What are the drawback of paypal recurring method ?

Database related

  • Difference between MyISAM over InnoDB.
  • Difference between unique key and primary key.
  • mysql_connect() and mysql_pconnect().
  • mysql_fetch_array and mysql_fetch_object and mysql_fetch_assoc.
  • Difference between left join and right join ?
  • Sql injection and use of mysql_real_escape_string ?
  • What do you mean by referential integrity ?
  • How can you optimize the database ?
  • What are indexes in mysql ?
  • How can you take backup of database using mysql query ?
  • What version of PHP,Mysql and Apache you are using ?

HTML,CSS,Javascript and JQuery (Javascript Library) and Other.

  • Tags of html5.
  • Advantage and disadvantage of AJAX.
  • What is SOAP ?
  • How can you update/change class of a element using jQuery ?
  • What is DOM ?
  • What is the use of .htaccess ?
  • Ajax object in IE and other browsers.
  • AJAX states.
  • What is the difference between get and post methods ?

Happy browsing 🙂