Category: PHP

Streaming File to the Browser

Hi Guys,

I hope you all are well. Today I am going to write post on How can make to user download the file from the another website without showing them that the file is actually coming from another server?

This can help many beginners PHP User to to Hide File URL Location in PHP. Here is the example how can u fetch file from other website and give download to the user like its downloading from our website.

Here is the Nice code:

<?php
	$file="http://example.com/example.jpg"; // replace this URL with your URL

	header('Content-Description: File Transfer');
	header('Content-Type: application/octet-stream');
	header('Content-Disposition: attachment; filename='.basename($file));
	header('Content-Transfer-Encoding: binary');
	header('Expires: 0');
	header('Cache-Control: must-revalidate');
	header('Pragma: public');
	header('Content-Length: ' . filesize($file));
	ob_clean();
	flush();
	readfile($file);
	exit;
?>

Very Easy to understand.

Ask if you Have any query.

Thank you.. 🙂

 

URL Rewriting Using htaccess file and PHP Apache

Hello friends,

From long time I was wondering how this URL rewriting is working. I have seen many website with pretty URLs. Also I found the URL Rewriting also helps in Better SEO (Search Engine Optimization).

After Reading bunch of tutorial and forums, I think this is very easy to make just few steps to follow and need knowledge of regular expression.

Steps for Implementing URL rewrite in you website.

  1. Enable mod_rewrite in Apache Server
  2. Create Htaccess file.
  3. Call the URL with New URL Defined.

Enabling mod_rewrite in Apache Server

For enabling mod_rewrite on Apache Server follow these steps:

  1. Find http.conf file in Apache server. Generally this file resides in conf folder of Apache installation PATH. XAMPP server path is C:\xampp\apache\conf on windows. Probably WAMP Path is C:\wamp\apache\conf.
  2. Find the line #LoadModule rewrite_module modules/mod_rewrite.so in the “httpd.conf” file. You can do this easily by searching the keyword “mod_rewrite” from find menu.
  3. Uncomment the line. http.conf file use # to comment the line. So remove the # from begining of the line.
  4. Restart the server. In WAMP you can restart the server by click the icon of WAMP in system tray in right bottom side of the windows. For XAMPP you can open XAMPP control and restart the server.
  5. You can check the mod_rewrite is enabled using phpinfo();

Create HTACCESS file

Lets consider one real world example for creating and understading HTACCESS file and its rules. HTACCESS file uses RewriteRule for define the rule for URL rewriting. This will show you good example for regular expression, rewrite rules & conditions.

For example, create file testhtaccess.php. Write

"This is PHP HTACCESS Test File"

Create second file testhtaccess.html and Write

"This is HTML HTACCESS Test File".

This is simple text written in the both the files so that we can differentiate when we rewrite the URL which file is called.

Create Third file .htaccess in same folder of the server where these two files are and Write

RewriteEngine On
RewriteRule ^/?testhtaccess\.html$ testaccess.php [L]

The first line turns RewiteEnging On. It will allow the server to rewrite the URL. Second line is the rule for URL rewriting. “^/” says that from starting any type of character and any number of character are allowed. Then there is “?testhtaccess\.html”  \ is for escaping the . in name and there is $ which implies that this is end for rule. This is first Parameter for RewriteRule. Now second parameter tells which files to call when url is matched.

So here when we call testaccess.html file is will be rewite the url and call testhtaccess.php file. This will done internally and URL remains the same.

Lets go now little complex for this. lets say that we have URL and Query String like as below:

http://mywebsite.com/details.php?city=cityname&company=companyname

we need to rewrite is like

http://mywebsite.com/cityname/companyname

Now we have to tell the apache that whenever this second rewrited url called it should internally call first URL with query string. Now for the ditails.php script to read and parse the query string, we’ll need to use regular expressions to tell mod_rewrite how to match the two URIs. For this you should have knowledge of regular expression. Even though I am going to explain some key factor of regular expression.

. (dot) – Matches any Single Character eg. c.t will match cat, cut, cot

+ (Plus) – repeates the previous match one more time

* (asterik) – repeats the previous match zero or mote times

? (question mark) – Makes the match optional

^ (anchor) – matches beginning of the string

$ (anchor) – matches end of the string

( ) – group several character into single unit

[ ] -a character class – matches one of the characters. it used for range of the character.

 [^ ] – negative character class – matches any character not specified.

Note: ! character can be used before a regular  expression to negate it.

Now for our example we can use

^([a-zA-Z_]+)/([a-zA-Z_]+)$

or

(.*)/(.*)

for replace Rewrite URL with Actual URL. Using ( ) we can make a variable which can be used on later. This Variable can accessed by

$1

Value incremented automatically on the sequence of occurring of the ( ).

RewriteRule ^/?([a-zA-Z_]+)/([a-zA-Z_]+))$ details.php?city=$1&company=$2 [L]

This will replace the Rewrite URL with Actual One.  [a-zA-Z_]+ will match any string in lowercase or Uppercase. Its in small bracket ( ) so that it store its value in $1 and when it occurs second time it will store its value in $2.

This is so simple as we can see. I have written this post for the beginners like me. I written what I learn reading other forums and blog which are seems to be very complex for understanding it.

Any Correction and advice from you friends will be appreciated.

Thank you Please comment here if any questions.. 🙂

How to Improve MySQL Large Database Performance

Hello friends,

This is my first post for the blog. Recently I have worked on two large database projects on   backend MySQL Database. During the period of the project I came across with many problems and somehow I managed them all.

Many of you also came across with the same MySQL Database problem with Performance. Query is not running well etc. During this period  I read many blogs and forums to solve these problems. I have figured out some tips or can say some points which we should taken care of.

Database Engine (MYISAM vs. Innodb)

Both MySQL Database engines have its own pros and cons that we have to decide which type of db engine will work great for us. Below are some concerns with this two engines:

MYISAM

  • MYISAM use less memory
  • It allows full text search
  • It locks the table while writing
  • It is useful for application in which reading is high and fewer write

InnoDB

  • It uses more memory
  • It does not support full text search
  • InnoDB provides faster performance
  • It lock the table at row level while writing to the table
  • It works great for the application which make extensive use of read and write both

 

Good Database Design

Good database design is a backbone for the application performance. Bad design makes application performance less. Table must be normalized. Data Structure is the main factor which must be developed carefully. Every Developer must give time for each table and fields for making good design. You should give proper data type to each field. When you done with database creation, you would like to see what is MySQL suggest you for your database table. Here is the Command which can help you to get this information:

ANALYZE TABLE <table-name>;

You can find full description here: http://dev.mysql.com/doc/refman/5.5/en/analyze-table.html

 Indexes

What many of us is knowing that indexes help us to increase the speed of query. Many times indexes create confusion in mind. Creating of proper indexes for the table is necessary but do make table overhead of indexes as indexes take space on the disk. So it increases the workload on the disk. Working on my project I many time need to add and delete column from large table which takes so much time. For increasing performance we can make index ON of OFF. so before whenever I start my database operation I make the index key off and do the operation when operations completed I again makes indexes ON. So rather than making new indexes on my each operation, it will make new index when I male Index on so its only one time. for turning on and index I use below syntax:

Disable Indexes:  ALTER TABLE table_name DISABLE KEY
Enable Indexes: ALTER TABLE table_name ENABLE KEY

 

Tuning MySQL

Hardware makes as important role as other things in database tuning. Our hardware needs just as much attention and tuning as our database and script does. It is also need to check MySQL Configuration file what type of changes we have make to the configuration. There is one tool available which is perl script. You can download and Install on server It tells that which type of configuration change you can make improve the performance.

 

Note: This are the simple things which I feel good to use and take care for better performance.