Difference between session and cookies?
Ans:- 1. session stored at server while cookie get stored at client’s web browser.
2. session are stored as an object on server side on the path specified in the php.in file for session_save path variable while cookies are passed as header and stored on client’s web browser as text file.
3. session variables are exists only when session doesn’t expires while cookies[persistent not session] can be stored for future time also and can be used to handle user’s preference.
what are encryption methods available in php and mysql?Difference between sha1 and md5?
Ans:- some encryption methods available in php are md5,sha1,encrypt,password.Difference between sha1 and md5 encryption is that sha1 take more space than md5 in terms of storing information in the database.Some encryption available in mySql are password,MD5,encrypt.
What is Ajax & how it works?
Ans:- AJAX stands for asynchronous javascript and xml.It’s asynchronous this script doesn’t wait for the response.Regardless of this it can make another request without waiting for the response.Fist of all it creates XMLHttpRequest object by which it makes a request.and when response comes back script handover it to another function which will check for the response readyStatus and returns the response.
Oops principles?
Ans:- Polymorphism [not supported in PHP]
Encapsulation
Abstraction
Dynamic binding
class and Object
for more detail please refer http://in2.php.net/manual/en/language.oop5.php
Mysql Joins?
Ans:- I don’t have idea but know about types.Cross,Left,right,inner and outer join.
Strings and array functions.array_walk,in_array?
Ans:- check function list available on
http://in2.php.net/manual/en/ref.array.php [for array]
http://in2.php.net/manual-lookup.php?pattern=string〈=en [for strings function]
Difference between include,include_once,require,require_once?
Ans:- Unlike include(), require() will always read in the target file, even if the line it’s on never executes. If you want to conditionally include a file, use include(). The conditional statement won’t affect the require(). However, if the line on which the require() occurs is not executed, neither will any of the code in the target file be executed.include() may give warning and proceed further but require() will hault whenever warning/error faced in the script.include_once(),require_once() as name suggest can be used to include a file only one.[useful in case we include a class file]
How can we submit a form without a submit button?
Ans:- you can call a function in javascript onclick event of any form element/link and in the function you amy use document.formName.submit(); to submit the form
What is the difference between mysql_fetch_object, mysql_fetch_rows and mysql_fetch_array?
Ans:- mysql_fetch_object will return an object by which we can access the database fields records while mysql_fetch_aaray and mysql_fetch_rows return array of database records.mysql_fetch_row will not return associative array while mysql_array will return associative array too.
What is the difference between $message and $$message?
$message is used as a variable while $message can be used to assign a value as variable.for eg:
$message=’uttam’;
$message=’kumar’;
in this case $kumar will give you value as ‘uttam’.
What is meant by nl2br()?
Returns string with ‘
’ inserted before all newlines(\n).
$msg=”these are \n interview question”;
$nl2brmsg=nl2br($msg);
$nl2brmsg will return value as “these are
interview question”.
Basic level Interview Questions - PHP
