PHP Questions and Answers

PHP is an important part of the web world, and every web developer should have the basic knowledge in PHP. Common PHP questions, which should help you become a best PHP developer.

how to create a table in mysql using php

Sudheesh.R

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

CREATE TABLE statement
<?php
$con=mysqli_connect(“example.com”,”user”,”pass”,”my_db”);
// Check connection
if (mysqli_connect_errno()) {
echo “Failed to connect to MySQL: ” . mysqli_connect_error();
}

// Create table
$sql=”CREATE TABLE users(FirstName CHAR(30),LastName CHAR(30),Age INT)”;

// Execute query
if (mysqli_query($con,$sql)) {
echo “Table users created successfully”;
} else {
echo “Error creating table: ” . mysqli_error($con);
}
?>

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

Sudheesh.R

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.

STRSTR()

<?php

$email = ‘name@example.com’;
$domain = strstr($email, ‘@’);
echo $domain; // prints @example.com

$user = strstr($email, ‘@’, true); // As of PHP 5.3.0
echo $user; // prints name

?>

What is the purpose of the following files having extensions: frm, myd, and myi? What these files contain?

Sudheesh.R

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,

what are the different types of errors in php?

Sudheesh.R

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