PHP Interview Questions and Answers - V

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PHP Interview Questions and Answers - V

How to reset/destroy a cookie ?
Reset a cookie by specifying expire time in the past:
Example: setcookie('Test',$i,time()-3600); // already expired time

Reset a cookie by specifying its name only
Example: setcookie('Test');

What types of images that PHP supports ?
Using imagetypes() function to find out what types of images are supported in your PHP engine.
imagetypes() - Returns the image types supported.
This function returns a bit-field corresponding to the image formats supported by the version of GD linked into PHP. The following bits are returned, IMG_GIF | IMG_JPG | IMG_PNG | IMG_WBMP | IMG_XPM.

Check if a variable is an integer in JAVASCRIPT ?
var myValue =9.8;
if(parseInt(myValue)== myValue)
alert('Integer');
else
alert('Not an integer');

Tools used for drawing ER diagrams.
Case Studio
Smart Draw

How can I know that a variable is a number or not using a JavaScript?
Answer 1:
bool is_numeric( mixed var)
Returns TRUE if var is a number or a numeric string, FALSE otherwise.

Answer 2:
Definition and Usage
The isNaN() function is used to check if a value is not a number.

Syntax
isNaN(number)

Parameter Description
number Required. The value to be tested

How can we submit from without a submit button?
Trigger the JavaScript code on any event ( like onSelect of drop down list box, onfocus, etc ) document.myform.submit(); This will submit the form.

How many ways can we get the value of current session id?
session_id() returns the session id for the current session.

How can we destroy the cookie?
Set the cookie with a past expiration time.

What are the current versions of Apache, PHP, and MySQL?
PHP: PHP 5.1.2
MySQL: MySQL 5.1
Apache: Apache 2.1

What are the reasons for selecting LAMP (Linux, Apache, MySQL, Php) instead of combination of other software programs, servers and operating systems?
All of those are open source resource. Security of Linux is very more than windows. Apache is a better server that IIS both in functionality and security. Mysql is world most popular open source database. Php is more faster that asp or any other scripting language.

What are the features and advantages of OBJECT ORIENTED PROGRAMMING?
One of the main advantages of OO programming is its ease of modification; objects can easily be modified and added to a system there by reducing maintenance costs. OO programming is also considered to be better at modeling the real world than is procedural programming. It allows for more complicated and flexible interactions. OO systems are also easier for non-technical personnel to understand and easier for them to participate in the maintenance and enhancement of a system because it appeals to natural human cognition patterns. For some systems, an OO approach can speed development time since many objects are standard across systems and can be reused. Components that manage dates, shipping, shopping carts, etc. can be purchased and easily modified for a specific system.

How can we get second of the current time using date function?
$second = date("s");