php questions and answers for exams
very short
answer type questions
1.)PHP stands for HYPERTEXT PREPROCESSOR.
2)Define PHP?
Ans.
PHP is a web server side scripting language. PHP scripts are executed at web
server. Their output which is pure HTML is returned to the requesting browser.
3.) Define Homepage?
Ans.
A homepage is a web page that serer as the starting point of website. It is the
default webpage that loads when you visit a web address that only contains
domain name.
4.) Define Array?
Ans.
An array is a data structure that contains a group of elements. Typically these
elements are all of the same data type ,such as an integer or string.
5.) What is the use of “print”
statement in php?
Ans.It
is used to output data to screen. but difference is that it has a return value
of 1 so it can be used in expression it can take one argument.
6.) What is the use of ”echo” statement
in php?
Ans.
It is also used to output data to the screen but the difference that it has no
return value it can take multiple parameters
7.) What is the use of strops()
function in PHP?
Ans.
It is used for finding a substring within a string
Syntax:-
Strops($haystack,$needle,$offset)
Eg:-
<?
php
$name=”mathew”;
Echo
strpos ($name,”na”);
Echo
strops ($name,”hew”);
Echo
strops($name,”m”);
?>
8.) Define SQL?
Ans.
Sql stands for structured query language .sql is used to communicate with a
database. It is the standard language for relational database management
system.
9.)Define constant?
Ans.
A constant like variable is a temporary placeholder in memory that holds a
value .its value never changes.
x.) What is the use of var_dump()
function in PHP?
Ans. The var_dump function display structured
information about variables/expressions including its type and value.
11.)what
is the use of count() function in PHP?
Ans. The count() function is used to count elements
of an array or the properties of an object
Syntax:-
Count (array-name, mode)
12.)
How to retrieve a cookie value?
Ans. A cookie is often used to identify a user . A
cookie is a small file that the server embeds on the user’s computer
For retrieving cooking eg is—
The following example retrieve a cookie named “user
” with the value”johndoe”.The cookie
will expire after 30 days
(86400*30).
Eg:-
<?php
$cookie_name=”user”;
$cookie_value=”john
doe”;
Setcookie($cookie_name,$cookie_value,time()+(86400*30),”/”a
?>
The”/” means that the cookie is available in entire
website
13.)
Define break statement?
Ans. Break statement means it is encountered inside
a loop the loop is immediately terminated and the program control resumes at
the next statement following the loop.
14.)
Define primary key?
Ans. A primary key is special relational database
table column designated to uniquely identify all table records. It must contain
a unique value for each row of data .it cannot contain null value.
15.)What
is the purpose of session variable in
php?
Ans. When we work with an application we open it do
some changes, and than we close it this is much like a session .the computer
knows who we are. It knows when we start the application and when we end. but
on internet there is one problem the web
server does not known who we are or what we do bcoz the http address doesn't
maintain state. This problem is solved by session variable. Session variable
stores the user information to be used across multiple pages.
16.)Write
down the command for creating a mysql connection?
Ans. command for creating connection is:
$conn=myli_connect($servername,$username,$password);
17.)Define
authorization?
Ans. Authorization is the process of giving someone permission
to do or have something. In multi user computer system a system
administrator defines for the system
which user are allowed access to the system and what privilege for use.
18.)What is an auto
incremented field?
Ans. Auto increment allows a
unique number to be generated automatically when a new record is inserted into
a table. Often this is the primary key field that we would like to be created
automatically every time a new record is inserted .
19.) Define the term loop?
Ans. A loop can be thought of
as something that is wrapped around the php code special to make it happen
again and again.
there are three types of
loops-
*for loop
*while loop
*do-while loop
20.)what are string
variables?
Ans .like numeric variable
,string variable can have labels and missing value declaration although missing
string values cannot be longer than 8 character. string can be up to 32767
character long.
21.)How the php script block
is initiated?
Ans.
<?php
____
____
?>
22.)What is command for
setting cookie in php?
Ans.set_cookie
(name,value,expire,path,domain,secure,http only);
only the name parameter is required,
all other parameters are optional.
23.)Define API library?
Ans. application programming
is a set of subroutine definition ,protocol, and tools for building application
software. A good APL library makes it easier to develop a computer program by
providing all the building blocks, which are then put together by the
programmer.
24.)What is the use of sql?
Ans. Sql is used to
communicate with database.sql statements are used to perform tasks such as update data on a database or retrieve
data from a database.
25.)Define multidimensional
array?
Ans. A multidimensional array
is an array containing one or more arrays.
26.)What is comment?
Ans. comments in php are
similar to comments that are used in html. The php comment syntax always begins
with a special character sequence and all text that appear between the start of
the comment and end will be ignored.
there are two types of
comments.
(i)single line
comment("//"or"#")
(ii)multiple line
comment("/*"or"*/")
27.) how can we declare a
constant?
Ans. Syntax:-
Define (name,value,case-insensitive)
Name: specifies the name of constant
Value: specifies the value of the constant
Case-Insensitive: Specifies Whether the
Constant name should be case –insensitive.
Eg:-<?php
Define(“GREETING”,”Welcom to
W3Schools.com!”);
Echo GREETING;
?>
28.) What is returning value
in PHP? Give examples.
Ans: A function can return a
value using the return statement in conjunction with a value or object . Return
stops the execution of the function and sends the value back to the calling
code.
Eg:-<?php
Function Sum($x,$y)
{
$z=$x+$y;
return $z;
}
Echo
“5+10=”.Sum((5,10).”<br>”;
Echo”7+13=”.Sum(7,13).”<br>”;
Echo”2+4=” Sum(2,4);
?>
29.) How can we create user
login?
Ans: Steps to create user :
1) Implementing user authentication mechanism
2) Building the registration system
3) Creating the config file
4) Creating the registration form
30.) Define PHP mail?
Ans: Syntax: mail(to subject,
message, headers, parameters);
31.) Write the syntax of for
loop?
Ans: Syntax:
for(intialization;conditional;increment/decrement)
{
Code to executed;
}
32.) What is client server
design?
Ans: The client server model
ios the distributed application structure that partition tasks or workloads
between the provides of a resource or service called servers and service
33.) What do you mean by
variable function?
Ans: Variable functions are those functions that
wont with language constructs such as echo ,print, unset (),empty() Include,
require and the like. PHP support the concept of variable functions. this means
that if a variable name has parenthesis appended it , PHP will look for a
function with the same name as whatever the variables evaluates to and will
attempts to execute it.
34.) What is use of isset()
funcation?
Ans: The isset() function is
used to check wheather a variable is set or not. If a variable is already unset
with unset() function, it will no longer be set. The issest() function return
false if testing variable contain a Null value.
Syntax: isset(Variable1,
Variable2…)
35.) What is the difference
between array and function?
Ans: Array:-
i) An array is a block of
memory.
ii) Array are of three types-
* Indexed
* Associative
* Multi-dimensional
Function:-
i) A function is a set of
lines code.
ii) Functions are of two
types-
* user-defined functions
* built-in functions
36.) What is PHP.INI file?
Ans: It is the default
configuration file for running applications that require PHP . It is used to
control variables such as upload sizes file time out and resource limits.
37.) Who is the father of
PHP?
Ans: “Rasmuslerdorf” is the
father or PHP.
38.) Which function is used
to determine the length of array?
Ans: int length() function is
used to determine the length of array.
39.) What is password
element?
Ans: It provide a way for the
user to securely enter a password. The element is presented as a one-line plain
text editor control in which the text is
obscured so that it can not be read, usually by replacing each character with a
symbol such as the asterisk (“*”) or a dot (“.”).
40.) Define Web Browser?
Ans: A web browser is a
software application for retrieving, presenting and travelling information resource
on the world wide web.
41.) What is database?
Ans: A database is a
collection of information that is organized so that it can be easily accessed
managed and update. Data is organized into rows, columns and tables, and it is
indexed to make it easier to find relevant information
42.) Name any two built in function
used in PHP?
Ans: * include()
*header()
43.) Define PHP tags?
Ans: The PHP syntax is a set
of rules that define how a program should be written. A set of tags are used to
mark the beginning and end of a block of code in between which any amount of in
between which any amount code can be written.
44.) What is Mysql?
Ans: Mysql is an open source
relational database management system based on structured query language
Xamp/Wamp is a web development platform that uses Linux as the operating
system, Apache as the web server, Mysql as the relational database management
system.
45.) How we start the PHP
scripting block?
Ans: <?php
?>
46.) What is the use of
concatenation operator?
Ans: Concatenation operator
is used to concatenate two expressions that evaluate to character datatv type
or to numeric data type.
47.) What is strlen() function?
Ans: The strlen() function
returns the length of a string.
Syntax: Strlen (string)
Eg:-<?php
Echo strlen (“hello world”);
?>
48.) Write four arithmetic
operator?
Ans: The basic arithmetic
operation are addition, subtraction, multiplication and division .
49.) What is post increment
operator?
Ans: Post increment operator:
The increment numbers and strings. Arrays , objects are not effected.
For example : $a++
Returns $a then increments the
$a by one
50.) Define associative array
?
Ans: In associative array the
keys assigned to values can be arbitrary and user defined strings in the
following example the array uses keys instead of index number .
Eg: $ages = array
(“peter”=>22,”clerk”=>32,”john”=>28);
51.) Write a syntax to delete
data from a database ?
Ans: Syntax to delete data
from a database:
Delete from table_name
Where condition;
52.) Define php form validation ?
Ans: validation means check
the input submitted by the user. There are two types of validations are
available in php. There are as follows-
i) client –side validation
ii) server-side validation
53.) Define Get variable?
Ans: Get variable contains
the same initial information but is not a super global $_Get are different
variables and that php handles them as such.
Eg: <?php
Echo hello.html special char ($
Get[“name”]);
?>
54.) Define mode of file
handling?
Ans: file handling is an
important part of any web application. You can often need to open and process a
file for different tasks
Php manipulating files :php
has several functions for creating, reading , uploading and editing files.
55.) What are the loop
statements?
Ans: loops in php are used to
execute the same block of code a specified number of times. Php support the
four loop types.
i) for
ii) while
iii) do-while
iv) for each
