PHP

PHP Interview Questions and Answers:-

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What's PHP ?
 
The PHP Hypertext Preprocessor is a programming language that allows web developers to create dynamic content that interacts with databases. PHP is basically used for developing web based software applications. 

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What Is a Session? 
 
A session is a logical object created by the PHP engine to allow you to preserve data across subsequent HTTP requests.

There is only one session object available to your PHP scripts at any time. Data saved to the session by a script can be retrieved by the same script or another script when requested from the same visitor.

Sessions are commonly used to store temporary data to allow multiple PHP pages to offer a complete functional transaction for the same visitor.

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What is meant by PEAR in php?
 
PEAR is the next revolution in PHP. This repository is bringing higher level programming to PHP. PEAR is a framework and distribution system for reusable PHP components. It eases installation by bringing an automated wizard, and packing the strength and experience of PHP users into a nicely organised OOP library. PEAR also provides a command-line interface that can be used to automatically install "packages"

Answer2:
PEAR is short for "PHP Extension and Application Repository" and is pronounced just like the fruit. The purpose of PEAR is to provide:
A structured library of open-sourced code for PHP users
A system for code distribution and package maintenance
A standard style for code written in PHP
The PHP Foundation Classes (PFC),
The PHP Extension Community Library (PECL),
A web site, mailing lists and download mirrors to support the PHP/PEAR community
PEAR is a community-driven project with the PEAR Group as the governing body. The project has been founded by Stig S. Bakken in 1999 and quite a lot of people have joined the project since then.

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How can we know the number of days between two given dates using PHP?
 
Simple arithmetic:

$date1 = date('Y-m-d');
$date2 = '2006-07-01';
$days = (strtotime() - strtotime()) / (60 * 60 * 24);
echo "Number of days since '2006-07-01': $days";

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How can we repair a MySQL table? 

The syntex for repairing a mysql table is:

REPAIR TABLE tablename
REPAIR TABLE tablename QUICK
REPAIR TABLE tablename EXTENDED

This command will repair the table specified.
If QUICK is given, MySQL will do a repair of only the index tree.
If EXTENDED is given, it will create index row by row. 

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What is the difference between $message and $$message?
 
$message is a simple variable whereas $$message is a reference variable. Example:
$user = 'bob'

is equivalent to

$holder = 'user';
$$holder = 'bob';

They are both variables. But $message is a variable with a fixed name. $$message is a variable who's name is stored in $message. For example, if $message contains "var", $$message is the same as $var.

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What Is a Persistent Cookie? 
 
A persistent cookie is a cookie which is stored in a cookie file permanently on the browser's computer. By default, cookies are created as temporary cookies which stored only in the browser's memory. When the browser is closed, temporary cookies will be erased. You should decide when to use temporary cookies and when to use persistent cookies based on their differences:
*Temporary cookies can not be used for tracking long-term information.
*Persistent cookies can be used for tracking long-term information.
*Temporary cookies are safer because no programs other than the browser can access them.
*Persistent cookies are less secure because users can open cookie files see the cookie values.


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What does a special set of tags <?= and ?> do in PHP? 
 
The output is displayed directly to the browser.  

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How do you define a constant?
 
Via define() directive, like define ("MYCONSTANT", 100);

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What are the differences between require and include, include_once? 
 
require_once() and include_once() are both the functions to include and evaluate the specified file only once. If the specified file is included previous to the present call occurrence, it will not be done again.

But require() and include() will do it as many times they are asked to do.

The include_once() statement includes and evaluates the specified file during the execution of the script. This is a behavior similar to the include() statement, with the only difference being that if the code from a file has already been included, it will not be included again. The major difference between include() and require() is that in failure include() produces a warning message whereas require() produces a fatal errors.

All three are used to an include file into the current page.
If the file is not present, require(), calls a fatal error, while in include() does not.
The include_once() statement includes and evaluates the specified file during the execution of the script. This is a behavior similar to the include() statement, with the only difference being that if the code from a file has already been included, it will not be included again. It des not call a fatal error if file not exists. require_once() does the same as include_once(), but it calls a fatal error if file not exists.

File will not be included more than once. If we want to include a file once only and further calling of the file will be ignored then we have to use the PHP function include_once(). This will prevent problems with function redefinitions, variable value reassignments, etc.

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What is meant by urlencode and urldecode?
 
 urlencode() returns the URL encoded version of the given string. URL coding converts special characters into % signs followed by two hex digits. For example: urlencode("10.00%") will return "10%2E00%25". URL encoded strings are safe to be used as part of URLs.
urldecode() returns the URL decoded version of the given string.

string urlencode(str) - Returns the URL encoded version of the input string. String values to be used in URL query string need to be URL encoded. In the URL encoded version:

Alphanumeric characters are maintained as is.
Space characters are converted to "+" characters.
Other non-alphanumeric characters are converted "%" followed by two hex digits representing the converted character.

string urldecode(str) - Returns the original string of the input URL encoded string.

For example:

$discount ="10.00%";
$url = "http://domain.com/submit.php?disc=".urlencode($discount);
echo $url;

 
you will get "http://domain.com/submit.php?disc=10%2E00%25".

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How To Get the Uploaded File Information in the Receiving Script?

Once the Web server received the uploaded file, it will call the PHP script specified in the form action attribute to process them. This receiving PHP script can get the uploaded file information through the predefined array called $_FILES. Uploaded file information is organized in $_FILES as a two-dimensional array as:
$_FILES[$fieldName]['name'] - The Original file name on the browser system.
$_FILES[$fieldName]['type'] - The file type determined by the browser.
$_FILES[$fieldName]['size'] - The Number of bytes of the file content.
$_FILES[$fieldName]['tmp_name'] - The temporary filename of the file in which the uploaded file was stored on the server.
$_FILES[$fieldName]['error'] - The error code associated with this file upload.

The $fieldName is the name used in the <INPUT TYPE=FILE, NAME=fieldName>.

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What is the difference between mysql_fetch_object and mysql_fetch_array? 
 
MySQL fetch object will collect first single matching record where mysql_fetch_array will collect all matching records from the table in an array

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How can I execute a PHP script using command line? 
 
Just run the PHP CLI (Command Line Interface) program and provide the PHP script file name as the command line argument. For example, "php myScript.php", assuming "php" is the command to invoke the CLI program.
Be aware that if your PHP script was written for the Web CGI interface, it may not execute properly in command line environment. 

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I am trying to assign a variable the value of 0123, but it keeps coming up with a different number, what’s the problem? 
 
PHP Interpreter treats numbers beginning with 0 as octal. Look at the similar PHP interview questions for more numeric problems.

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What’s PHP ?

The PHP Hypertext Preprocessor is a programming language that allows web developers to create dynamic content that interacts with databases. PHP is basically used for developing web based software applications.What Is a Session?

A session is a logical object created by the PHP engine to allow you to preserve data across subsequent HTTP requests.There is only one session object available to your PHP scripts at any time. Data saved to the session by a script can be retrieved by the same script or another script when requested from the same visitor.Sessions are commonly used to store temporary data to allow multiple PHP pages to offer a complete functional transaction for the same visitor. 

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What is meant by PEAR in php?

PEAR is the next revolution in PHP. This repository is bringing higher level programming to PHP. PEAR is a framework and distribution system for reusable PHP components. It eases installation by bringing an automated wizard, and packing the strength and experience of PHP users into a nicely organised OOP library. PEAR also provides a command-line interface that can be used to automatically install “packages”

PEAR is short for “PHP Extension and Application Repository” and is pronounced just like the fruit. The purpose of PEAR is to provide:

A structured library of open-sourced code for PHP users

A system for code distribution and package maintenance

A standard style for code written in PHP

The PHP Foundation Classes (PFC),

The PHP Extension Community Library (PECL),

A web site, mailing lists and download mirrors to support the PHP/PEAR community

PEAR is a community-driven project with the PEAR Group as the governing body. The project has been founded by Stig S. Bakken in 1999 and quite a lot of people have joined the project since then. 

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How can we know the number of days between two given dates using PHP? 

Simple arithmetic:

$date1 = date(‘Y-m-d’);

$date2 = ’2006-07-01′;

$days = (strtotime() – strtotime()) / (60 * 60 * 24);

echo “Number of days since ’2006-07-01′: $days”;

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How can we repair a MySQL table?  

The syntex for repairing a mysql table is:

REPAIR TABLE tablename

REPAIR TABLE tablename QUICK

REPAIR TABLE tablename EXTENDED

This command will repair the table specified.

If QUICK is given, MySQL will do a repair of only the index tree.

If EXTENDED is given, it will create index row by row. 

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What is the difference between $message and $$message? 

$message is a simple variable whereas $$message is a reference variable. Example:

$user = ‘bob’

is equivalent to

$holder = ‘user’;

$$holder = ‘bob’;Anwser 2:

They are both variables. But $message is a variable with a fixed name. $$message is a variable who’s name is stored in $message. For example, if $message contains “var”, $$message is the same as $var.

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What Is a Persistent Cookie?

A persistent cookie is a cookie which is stored in a cookie file permanently on the browser’s computer. By default, cookies are created as temporary cookies which stored only in the browser’s memory. When the browser is closed, temporary cookies will be erased. You should decide when to use temporary cookies and when to use persistent cookies based on their differences:

*Temporary cookies can not be used for tracking long-term information.

*Persistent cookies can be used for tracking long-term information.

*Temporary cookies are safer because no programs other than the browser can access them.

*Persistent cookies are less secure because users can open cookie files see the cookie values.

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What does a special set of tags <?= and ?> do in PHP?

The output is displayed directly to the browser.How do you define a constant?

Via define() directive, like define (“MYCONSTANT”, 100); 

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What are the differences between require and include, include_once?

require_once() and include_once() are both the functions to include and evaluate the specified file only once. If the specified file is included previous to the present call occurrence, it will not be done again.But require() and include() will do it as many times they are asked to do.

The include_once() statement includes and evaluates the specified file during the execution of the script. This is a behavior similar to the include() statement, with the only difference being that if the code from a file has already been included, it will not be included again. The major difference between include() and require() is that in failure include() produces a warning message whereas require() produces a fatal errors.

All three are used to an include file into the current page.

If the file is not present, require(), calls a fatal error, while in include() does not.

The include_once() statement includes and evaluates the specified file during the execution of the script. This is a behavior similar to the include() statement, with the only difference being that if the code from a file has already been included, it will not be included again. It des not call a fatal error if file not exists. require_once() does the same as include_once(), but it calls a fatal error if file not exists.

File will not be included more than once. If we want to include a file once only and further calling of the file will be ignored then we have to use the PHP function include_once(). This will prevent problems with function redefinitions, variable value reassignments, etc.

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What is meant by urlencode and urldecode?

urlencode() returns the URL encoded version of the given string. URL coding converts special characters into % signs followed by two hex digits. For example: urlencode(“10.00%”) will return “10%2E00%25″. URL encoded strings are safe to be used as part of URLs.

urldecode() returns the URL decoded version of the given string.Anwser 2:

string urlencode(str) – Returns the URL encoded version of the input string. String values to be used in URL query string need to be URL encoded. In the URL encoded version:

Alphanumeric characters are maintained as is.

Space characters are converted to “+” characters.

Other non-alphanumeric characters are converted “%” followed by two hex digits representing the converted character.

string urldecode(str) – Returns the original string of the input URL encoded string.For example:

$discount =”10.00%”;

$url = “http://domain.com/submit.php?disc=”.urlencode($discount);

echo $url;You will get “http://domain.com/submit.php?disc=10%2E00%25″.

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How To Get the Uploaded File Information in the Receiving Script?

Once the Web server received the uploaded file, it will call the PHP script specified in the form action attribute to process them. This receiving PHP script can get the uploaded file information through the predefined array called $_FILES. Uploaded file information is organized in $_FILES as a two-dimensional array as:

$_FILES[$fieldName]['name'] – The Original file name on the browser system.

$_FILES[$fieldName]['type'] – The file type determined by the browser.

$_FILES[$fieldName]['size'] – The Number of bytes of the file content.

$_FILES[$fieldName]['tmp_name'] – The temporary filename of the file in which the uploaded file was stored on the server.

$_FILES[$fieldName]['error'] – The error code associated with this file upload.

The $fieldName is the name used in the <INPUT TYPE=FILE, NAME=fieldName>. 

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What is the difference between mysql_fetch_object and mysql_fetch_array? 

MySQL fetch object will collect first single matching record where mysql_fetch_array will collect all matching records from the table in an array

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How can I execute a PHP script using command line? 

Just run the PHP CLI (Command Line Interface) program and provide the PHP script file name as the command line argument. For example, “php myScript.php”, assuming “php” is the command to invoke the CLI program.

Be aware that if your PHP script was written for the Web CGI interface, it may not execute properly in command line environment.I am trying to assign a variable the value of 0123, but it keeps coming up with a different number, what’s the problem?

PHP Interpreter treats numbers beginning with 0 as octal. Look at the similar PHP interview questions for more numeric problems.Would I use print “$a dollars” or “{$a} dollars” to print out the amount of dollars in this example?

In this example it wouldn’t matter, since the variable is all by itself, but if you were to print something like “{$a},000,000 mln dollars”, then you definitely need to use the braces.What are the different tables present in MySQL? Which type of table is generated when we are creating a table in the following syntax: create table employee(eno int(2),ename varchar(10))?

Total 5 types of tables we can create

1. MyISAM2. Heap

3. Merge

4. INNO DB

5. ISAM

MyISAM is the default storage engine as of MySQL 3.23. When you fire the above create query MySQL will create a MyISAM table.

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How To Create a Table? 

If you want to create a table, you can run the CREATE TABLE statement as shown in the following sample script:

<?php

include “mysql_connection.php”;

$sql = “CREATE TABLE Tech_links (“

. ” id INTEGER NOT NULL”

. “, url VARCHAR(80) NOT NULL”

. “, notes VARCHAR(1024)”

. “, counts INTEGER”

. “, time TIMESTAMP DEFAULT sysdate()”

. “)”;

if (mysql_query($sql, $con)) {

print(“Table Tech_links created.\n”);

} else {

print(“Table creation failed.\n”);

}

mysql_close($con);

?>

Remember that mysql_query() returns TRUE/FALSE on CREATE statements. If you run this script, you will get something like this:

Table Tech_links created.

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How can we encrypt the username and password using PHP? 

You can encrypt a password with the following Mysql>SET PASSWORD=PASSWORD(“Password”);

You can use the MySQL PASSWORD() function to encrypt username and password. For example,

INSERT into user (password, …) VALUES (PASSWORD($password”)), …);

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How do you pass a variable by value? 

Just like in C++, put an ampersand in front of it, like $a = &$b

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What is the functionality of the functions STRSTR() and STRISTR()? 

string strstr ( string haystack, string needle ) returns part of haystack string from the first occurrence of needle to the end of haystack. This function is case-sensitive.

stristr() is idential to strstr() except that it is case insensitive.When are you supposed to use endif to end the conditional statement?

When the original if was followed by : and then the code block without braces.How can we send mail using JavaScript?

No. There is no way to send emails directly using JavaScript.

But you can use JavaScript to execute a client side email program send the email using the “mailto” code. Here is an example:

function myfunction(form)

{

tdata=document.myform.tbox1.value;

location=”mailto:mailid@domain.com?subject=…”;

return true;

 }

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What is the functionality of the function strstr and stristr? 

strstr() returns part of a given string from the first occurrence of a given substring to the end of the string. For example: strstr(“user@example.com”,”@”) will return “@example.com”.

stristr() is idential to strstr() except that it is case insensitive.What is the difference between ereg_replace() and eregi_replace()?

eregi_replace() function is identical to ereg_replace() except that it ignores case distinction when matching alphabetic characters.

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How do I find out the number of parameters passed into function9. ? 

func_num_args() function returns the number of parameters passed in.What is the purpose of the following files having extensions: frm, myd, and myi? What these files contain?

In MySQL, the default table type is MyISAM.

Each MyISAM table is stored on disk in three files. The files have names that begin with the table name and have an extension to indicate the file type.

The ‘.frm’ file stores the table definition.

The data file has a ‘.MYD’ (MYData) extension.

The index file has a ‘.MYI’ (MYIndex) extension, 

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If the variable $a is equal to 5 and variable $b is equal to character a, what’s the value of $$b?

100, it’s a reference to existing variable.

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How To Protect Special Characters in Query String?

If you want to include special characters like spaces in the query string, you need to protect them by applying the urlencode() translation function. The script below shows how to use urlencode():

<?php

print(“<html>”);

print(“<p>Please click the links below”

.” to submit comments about TECHPreparation.com:</p>”);

$comment = ‘I want to say: “It\’s a good site! :->”‘;

$comment = urlencode($comment);

print(“<p>”

.”<a href=\”processing_forms.php?name=Guest&comment=$comment\”>”

.”It’s an excellent site!</a></p>”);

$comment = ‘This visitor said: “It\’s an average site! “‘;

$comment = urlencode($comment);

print(“<p>”

.’<a href=”processing_forms.php?’.$comment.’”>’

.”It’s an average site.</a></p>”);

print(“</html>”);

?>

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Are objects passed by value or by reference?

Everything is passed by value. 

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What are the differences between DROP a table and TRUNCATE a table? 

 DROP TABLE table_name – This will delete the table and its data.

TRUNCATE TABLE table_name – This will delete the data of the table, but not the table definition. 

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How do you call a constructor for a parent class?

parent::constructor($value)

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WHAT ARE THE DIFFERENT TYPES OF ERRORS IN PHP?

Here are three basic types of runtime errors in PHP:

1. Notices: These are trivial, non-critical errors that PHP encounters while executing a script – for example, accessing a variable that has not yet been defined. By default, such errors are not displayed to the user at all – although you can change this default behavior.

2. Warnings: These are more serious errors – for example, attempting to include() a file which does not exist. By default, these errors are displayed to the user, but they do not result in script termination.

3. Fatal errors: These are critical errors – for example, instantiating an object of a non-existent class, or calling a non-existent function. These errors cause the immediate termination of the script, and PHP’s default behavior is to display them to the user when they take place.

Internally, these variations are represented by twelve different error types

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What’s the special meaning of __sleep and __wakeup? 

__sleep returns the array of all the variables than need to be saved, while __wakeup retrieves them.

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How can we submit a form without a submit button? 

If you don’t want to use the Submit button to submit a form, you can use normal hyper links to submit a form. But you need to use some JavaScript code in the URL of the link. For example:

<a href=”javascript: document.myform.submit();”>Submit Me</a> Why doesn’t the following code print the newline properly? <?php $str = ‘Hello, there.\nHow are you?\nThanks for visiting techpreparation’; print $str; ?>

Because inside the single quotes the \n character is not interpreted as newline, just as a sequence of two characters – \ and n.

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Would you initialize your strings with single quotes or double quotes? 

Since the data inside the single-quoted string is not parsed for variable substitution, it’s always a better idea speed-wise to initialize a string with single quotes, unless you specifically need variable substitution.How can we extract string ‘abc.com ‘ from a string http://info@abc.com using regular expression of php?

We can use the preg_match() function with “/.*@(.*)$/” as

the regular expression pattern. For example:

preg_match(“/.*@(.*)$/”,”http://info@abc.com”,$data);

Ex: Assume we are logging in with username and password.

GET: we are submitting a form to login.php, when we do submit or similar action, values are sent through visible query string (notice ./login.php?username=…&password=… as URL when executi>

When we submit a form, which has the GET method it displays pair of name/value used in the form at the address bar of the browser preceded by url. Post method doesn’t display these values.

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What is the difference between the functions unlink and unset? 

unlink() is a function for file system handling. It will simply delete the file in context.

unset() is a function for variable management. It will make a variable undefined. 

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How come the code works, but doesn’t for two-dimensional array of mine? 

Any time you have an array with more than one dimension, complex parsing syntax is required. print “Contents: {$arr[1][2]}” would’ve worked.How can we register the variables into a session?

session_register($session_var);

$_SESSION['var'] = ‘value’;

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What are the different functions in sorting an array?

Sorting functions in PHP:

asort()

arsort()

ksort()krsort()

uksort()

sort()

natsort()

rsort()

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How can we know the count/number of elements of an array? 

2 ways:

a) sizeof($array) – This function is an alias of count()

b) count($urarray) – This function returns the number of elements in an array.

Interestingly if you just pass a simple var instead of an array, count() will return 1.

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How many ways we can pass the variable through the navigation between the pages? 

At least 3 ways:

1. Put the variable into session in the first page, and get it back from session in the next page.

2. Put the variable into cookie in the first page, and get it back from the cookie in the next page.

3. Put the variable into a hidden form field, and get it back from the form in the next page.What is the maximum length of a table name, a database name, or a field name in MySQL?

Database name: 64 characters

Table name: 64 characters

Column name: 64 characters

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How many ways we can we find the current date using MySQL?

SELECT CURDATE();

SELECT CURRENT_DATE();

SELECT CURTIME();

SELECT CURRENT_TIME();

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Give the syntax of GRANT commands? 

The generic syntax for GRANT is as following

GRANT [rights] on [database] TO [username@hostname] IDENTIFIED BY [password]

Now rights can be:

a) ALL privilages

b) Combination of CREATE, DROP, SELECT, INSERT, UPDATE and DELETE etc.

We can grant rights on all databse by usingh *.* or some specific database by database.* or a specific table by database.table_name.Give the syntax of REVOKE commands?

The generic syntax for revoke is as following

REVOKE [rights] on [database] FROM [username@hostname]

Now rights can be:

a) ALL privileges

b) Combination of CREATE, DROP, SELECT, INSERT, UPDATE and DELETE etc.We can grant rights on all database by using *.* or some specific database by database.* or a specific table by database.table_name. 

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What is the difference between CHAR and VARCHAR data types? 

CHAR is a fixed length data type. CHAR(n) will take n characters of storage even if you enter less than n characters to that column. For example, “Hello!” will be stored as “Hello! ” in CHAR(10) column.

VARCHAR is a variable length data type. VARCHAR(n) will take only the required storage for the actual number of characters entered to that column. For example, “Hello!” will be stored as “Hello!” in VARCHAR(10) column.

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Javascript

Javascript Interview Questions and Answers

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In this section, I have selected advanced javascript interview questions and answers for all levels of candidates(entry level, advanced level, expert level). Last few months I have been working to select best question and answer set for  javascript interview questions.I have written some  javascript  tutorials.

What are JavaScript types? 
Number, String, Boolean, Function, Object, Null, Undefined.

How do you convert numbers between different bases in JavaScript?
Use the parseInt() function, that takes a string as the first parameter, and the base as a second parameter. So to convert hexadecimal 3F to decimal, use parseInt ("3F", 16);

What does "1"+2+3 evaluate to?
Since 1 is a string, everything is a string, so the result is 123.

How about 3+5+"8"?
Since 3 and 5 are integers, this is number arithmetic, since 8 is a string, it’s concatenation, so 88 is the result.

How do you submit a form using Javascript? 
Use document.forms[0].submit();

How do you assign object properties?
obj["age"] = 22 or obj.age = 22.

What’s a way to append a value to an array?
arr[arr.length] = value;

What does isNaN function do? 
Return true if the argument is not a number.

What’s relationship between JavaScript and ECMAScript?
ECMAScript is yet another name for JavaScript (other names include LiveScript). The current JavaScript that you see supported in browsers is ECMAScript revision 3.

How to read and write a file using javascript? 
I/O operations like reading or writing a file is not possible with client-side javascript.

How do you convert numbers between different bases in JavaScript? 
Use the parseInt() function, that takes a string as the first parameter, and the base as a second parameter. So to convert hexadecimal FF to decimal, use parseInt ("FF", 16);

What is negative infinity? 
It’s a number in JavaScript, derived by dividing negative number by zero.

How to set a HTML document's background color? 
document.bgcolor property can be set to any appropriate color.

What boolean operators does JavaScript support?
&&, and !

How to get the contents of an input box using Javascript? 
Use the "value" property.
var myValue = window.document.getElementById("textboxID").value;

How to determine the state of a checkbox using Javascript? 
var checkedP = window.document.getElementById("CheckBoxID").checked;

How to set the focus in an element using Javascript? 
<script> function setFocus() { if(focusElement != null) { document.forms[0].elements["myelementname"].focus(); } } </script>

How to access an external javascript file that is stored externally and not embedded? 
This can be achieved by using the following tag between head tags or between body tags.
<script src="raj.js"></script>How to access an external javascript file that is stored externally and not embedded? where abc.js is the external javscript file to be accessed.

What is the difference between an alert box and a confirmation box? 
An alert box displays only one button which is the OK button whereas the Confirm box displays two buttons namely OK and cancel.

What is a prompt box? 
A prompt box allows the user to enter input by providing a text box.

Can javascript code be broken in different lines? 
Breaking is possible within a string statement by using a backslash \ at the end but not within any other javascript statement.
that is ,
document.write("Hello \ world");
is possible but not document.write \
("hello world");

What looping structures are there in JavaScript?
for, while, do-while loops, but no foreach.

How do you create a new object in JavaScript?
var obj = new Object(); or var obj = {};

What is this keyword?
It refers to the current object.


What is the difference between SessionState and ViewState? 
ViewState is specific to a page in a session. Session state refers to user specific data that can be accessed across all pages in the web application.


What looping structures are there in JavaScript? 
for, while, do-while loops, but no foreach.

To put a "close window" link on a page ? 
<a href='javascript:window.close()' class='mainnav'> Close </a>

How to hide javascript code from old browsers that dont run it? 
Use the below specified style of comments <script language=javascript> <!-- javascript code goes here // --> or Use the <NOSCRIPT>some html code </NOSCRIPT> tags and code the display html statements between these and this will appear on the page if the browser does not support javascript

How to comment javascript code? 
Use // for line comments and
/*
*/ for block comments

Name the numeric constants representing max,min values 
Number.MAX_VALUE
Number.MIN_VALUE

What does javascript null mean? 
The null value is a unique value representing no value or no object.
It implies no object,or null string,no valid boolean value,no number and no array object.

How do you create a new object in JavaScript? 
var obj = new Object(); or var obj = {};

How do you assign object properties? 
obj["age"] = 23 or obj.age = 23.

What’s a way to append a value to an array? 
arr[arr.length] = value;


To set all checkboxes to true using JavaScript? 
//select all input tags
function SelectAll() {
var checkboxes = document.getElementsByTagName("input");
for(i=0;i<checkboxes.length;i++) {
if(checkboxes.item(i).attributes["type"].value == "checkbox") {
checkboxes.item(i).checked = true;
}
}
}

What does undefined value mean in javascript? 
Undefined value means the variable used in the code doesn't exist or is not assigned any value or the property doesn't exist.

What is the difference between undefined value and null value? 
(i)Undefined value cannot be explicitly stated that is there is no keyword called undefined whereas null value has keyword called null
(ii)typeof undefined variable or property returns undefined whereas typeof null value returns object

What is variable typing in javascript? 
It is perfectly legal to assign a number to a variable and then assign a string to the same variable as follows
example
i = 10;
i = "string";
This is called variable typing

Does javascript have the concept level scope? 
No. JavaScript does not have block level scope, all the variables declared inside a function possess the same level of scope unlike c,c++,java.

What are undefined and undeclared variables? 
Undeclared variables are those that are not declared in the program (do not exist at all),trying to read their values gives runtime error.But if undeclared variables are assigned then implicit declaration is done .
Undefined variables are those that are not assigned any value but are declared in the program.Trying to read such variables gives special value called undefined value.

What is === operator ? 
==== is strict equality operator ,it returns true only when the two operands are having the same value without any type conversion.


How to disable an HTML object ?
document.getElementById("myObject").disabled = true;

How to create a popup warning box?
alert('Warning: Please enter an integer between 0 and 1000.');

How to create a confirmation box? 
confirm("Do you really want to launch the missile?");

How to create an input box? 
prompt("What is your temperature?");

How to force a page to go to another page using JavaScript ? 
<script language="JavaScript" type="text/javascript" ><!-- location.href="http://rajeshstutorials.blogspt.com"; //--></script>

What's Math Constants and Functions using JavaScript? 
The Math object contains useful constants such as Math.PI, Math.E

Math.abs(value); //absolute value
Math.max(value1, value2); //find the largest
Math.random() //generate a decimal number between 0 and 1
Math.floor(Math.random()*101) //generate a decimal number between 0 and 100

What does the delete operator do? 
The delete operator is used to delete all the variables and objects used in the program ,but it does not delete variables declared with var keyword.

How to get value from a textbox?
alert(document.getElementById('txtbox1').value);

How to get value from dropdown (select) control?
alert(document.getElementById('dropdown1').value);

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Jobs at Coimbatore

Jobs at Coimbatore:-

BPO

spanco 

Coimbatore

Website:www.spancobpo.com

E-mail:recruitment.cbe@spancobpo.com

Jobs Requirements (if available then apply):

We are a domestic call center having association with a telecom giant currently looking out for candidates for our call center - inbound Voice process Candidate profile & Job Description: Qualification : 12th Pass/Diploma holders/Under graduates/Graduates. Age : 18-30 Sex : Male / Female
Languages: Good Communication skills in English mandatory and fluency in Tamil or Malayalam. Other Skills: Basic working knowledge of computers. Minimum typing speed of 10-15 Words per minute. Shifts: Flexible with shifts, for women the shift timings will be only till 8 p.m. Homemakers/Housewives are most welcome. Experience: 0 months to 1 year Work Place: Coimbatore
Details for Applying
Spanco BPO Services
No.C4, Rathinam Tech Park, Eachanari, Pollachi Road, Coimbatore 641021
Email : recruitment.cbe@spancobpo.com

 ------------------------------------------------------------------------------------------------------------

OSDI private limited

Coimbatore

Website:www.spancobpo.com

E-mail:recruitment.cbe@spancobpo.com

Job Description
We are a well established IT & IT Enabled Services company that is looking for experienced ePub and Data Conversion Operators for our office in Coimbatore. If publishing is your passion, apply immediately!

The following are the expectation from candidates applying for the position of Data Conversion / ePub Operators.

Must Have Skills

- Minimum 6 months experience in ePublishing & Data Conversion
- Good exposure in XML, HTML, XHTML
- Experience in ePUB, Mobi & Fixed Layouts
- Experience with Epsilon and other Text Editors
- Acrobat, Photoshop, MathType
- TeX, LaTeX and MathML
- Fluency in the English Language
- Good Analytical Skills

Other Skills

- Knowledge in limitations of various eBook devices
- Problem Identification and Trouble-Shooting
- Quick Grasping Ability
- Proofreading and style checking a plus
- Knowledge in PDF Compare a plus
- Flexible to work in shifts

Positions in Coimbatore. Salary not a constraint for the right candidate.

Salary will be on par with the best in the industry.

We are an equal opportunities employer. Application are welcomed from male and female candidates.

Jobs Requirements (if available then apply):

Must Have Skills

- Minimum 1 year Experience in ePublishing & Data Conversion

- Good exposure in XML, HTML, XHTML

- Experience in ePUB, Mobi & Fixed Layouts

- Experience with Epsilon and other Text Editors

- Acrobat, Photoshop, MathType

- TeX, LaTeX and MathML

- Fluency in the English Language

- Good Analytical Skills

------------------------------------------------------------------------------------------------------------
 
IT-technology

VectraForm
Coimbatore
Website: www.vectraform.net
E-Mail: jobs@vectraform.net

Job Requirements (if available then apply):

Computer Aided Design (CAD), Computer Aided Manufacturing (CAM), Computer Aided Engineering (CAE), Computer Aided Inspection (CAI), Computer Aided Reverse Engineering (CARE), Computer Aided Rapid Prototyping (CARP), Computer Aided Rapid Manufacturing (CARM), Computer Aided Rapid Tooling (CART).

------------------------------------------------------------------------------------------------------------
 
VInCom Technologies India Pvt Ltd
Coimbatore
Website: www.vincom.com
E-Mail: support@vincom.com

Job Requirements (if available then apply):

ASP.Net Professionals, Web designers, Project Co-ordinators, Marketing Executies.

 ------------------------------------------------------------------------------------------------------------

WebTeK
Coimbatore
Website: www.webteksolutions.co.uk
e-Mail: jobs@webteksolutions.co.uk

Job Requirements (if available then apply):

Software development, data and services, custom web application

------------------------------------------------------------------------------------------------------------
 
Wings Infonet Ltd
Coimbatore
Website: www.wings2000.com
e-Mail: coimbatore@WingsInfo.net

Job Requirements (if available then apply):

Software development, e-Accounting, e-payroll systems, e-Trade.

------------------------------------------------------------------------------------------------------------
 
X_Designe Ventures Pvt Ltd
Coimbatore
Website: www.xdesignventures.com
e-Mail: info@xdesignventures.com

Job Requirements (if available then apply):

Web page Under Construction

------------------------------------------------------------------------------------------------------------
 
365 MEDIA
Coimbatore
Website: www.365media.com
e-Mail: hrindia@365media.com

Job Requirements (if available then apply):

Web based development(Exp 2+), solid database(Exp 2+), Excellent knowledge of ASP, ASP.Net and C#, Strong knowledge of Microsoft SQL Server 2000/2005 and T-SQL, database design skills, AJAX / ATLAS, problem solving skills, Bsc or related degree with strong technical background.

 ------------------------------------------------------------------------------------------------------------

J-query

J-query interview questions and answer:-

posted by selvamface

What is Jquery?

jQuery is a JavaScript Library.

Which of the following is correct?

jQuery is a JavaScript Library
jQuery is a JSON Library

Answer :jQuery is a JavaScript Library

jQuery uses CSS selectors and XPath expressions to select elements?

False
True

Answer: True

Which sign does jQuery use as a shortcut for jQuery?

$ sign
% sign
? Sign

Answer: $ sign


Is jQuery a W3C standard?

Yes
No

Answer: NO


$("span"). What does it select?

All span elements
The first span element

Answer: All span elements

Is jQuery a library for client scripting or server scripting?

Client scripting
Server scripting

Answer: Client scripting

Is it possible to use jQuery together with AJAX?

Yes
No

Answer: Yes

The jQuery html() method works for both HTML and XML documents

True
False

Answer :False

jQuery code to set the background color of all span elements to blue?

$("span").style("background-color","blue");
$("span").manipulate("background-color","blue");
$("span").css("background-color","blue");
$("span").layout("background-color","blue");

Answer: $("span").css("background-color","blue");


$("span.intro"). What does it select?

The first span element with class="intro"
The first span element with id="intro"
All span elements with id="intro"
All span elements with class="intro"

Answer: All span elements with class="intro"

jQuery method to hide selected elements?

visible(false)
hidden()
display(none)
hide()

Answer: hide()

jQuery method to set one or more style properties for selected elements?

style()
css()
html()
 
Answer: css()

jQuery method is used to perform an asynchronous HTTP request?

jQuery.ajaxAsync()
jQuery.ajaxSetup()
jQuery.ajax()

Answer: jQuery.ajax()


What scripting language is jQuery written in?

VBScript
C++
JavaScript
C#

Answer: JavaScript

$("div#id1 .cl1"). What does it select?

The first element with id="cl1" inside any div element with class="id1"
All elements with class="cl1" inside the first div element with id="id1"
All div elements with id="id1" or class="cl1"

Answer: All elements with class="cl1" inside the first div element with id="id1"


Difference between onload() and document.ready() function used in jQuery?

• We can add more than one document.ready() function in a page.
• we can have only one onload function.
• Document.ready() function is called as soon as DOM is loaded.
• body.onload() function is called when everything (DOM, images..)gets loaded on the page.

JQuery Methods used to provide effects?

1. Show()
2. Hide()
3. Toggle()
4. FadeIn()
5. FadeOut()


What are the different type of selectors in Jquery?

1. CSS Selector
2. XPath Selector
3. Custom Selector

What does .size() method of jquery return ?

.size() method of jquery returns number of element in the object.


 How do you get the text value?

$("#textbox1").val();

 How do you check or uncheck a checkbox input or radio button?

1.$('#num1').attr('checked', true);// Check #num1

2.$('#num1').attr('checked', false);// Uncheck #num1

3.$("#num1").attr('checked', 'checked');// Check #num1

4.$("#num1").removeAttr('checked');// Uncheck #num1


Ajax Request in Jquery

$.ajax({
     url: 'test.php',
     success: function(response) {
        alert(response);
     },
     error: function(res) {
        alert(res.status);
     }
});


Explain the each() function.

$("#num").click(function(){
$("li").each(function(){
document.write($(this).text())
});
});

18 free social media icons

18Killer Free Social Media Icon Sets

Posted by Selvaraj.M

Fri, Sep 10, 2012 @ 09:30 AM

Social media is an incredibly effective tool for sharing content, boosting popularity, improving search engine optimization, and getting found on the internet.  Using actionable icons that integrate with the theme of your site, content, and online activities instead of bland generic ones will help encourage readers to share your content.  Finding the perfect icon set can take time, so we have decided to do some of the leg work for you.
Here is a collection of 50 free social media icon sets you can use to enhance your website. We have gathered these across the web. While some of these have different licenses, they have been created for use in a wide variety of materials. Click on the link for the set that you are interested in and it should take you to the page on the designer's site where you can find out more information or download the set.

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