PHP Questions

unlink()-deletes the given file from the file system.
unset() -makes a variable undefined.

 .htaccess is a configuration file running on Apache server.These .htaccess file used to change the functionality and features of apache web  server .

 e.g   .htaccess file used for url rewrite .

         .htaccess file used to make the site password protected.

         .htaccess file can restrict  some ip addresses ,so that on restricted ip adresses  site will not open.

As far PHP concern it only support single Inheritance in scripting. we can also use interface to achieve multiple inheritance.

1 : InnoDB provides us row level locking while MyISAM provides us table level locking.

2 : InnoDB offers foreign key constraints wheres in MyISAM does not have foreign key constraints.

3 : InnoDB does not have full text search wheres MyISAM provides us full text search.

move_uploaded_file( string filename, string destination)

The header() function sends a raw HTTP header to a client. We can use header() function for redirection of pages. It is important to notice that  header()  must be called before any actual output is seen..

CRYPT(), MD5()

<?php
$tomorrow = mktime(0, 0, 0, date("m") , date("d")+1, date("Y"));
$lastmonth = mktime(0, 0, 0, date("m")-1, date("d"), date("Y"));
echo ($tomorrow-$lastmonth)/86400;
?>