Why php & mysql suits better/ (have better combination) for developing online applications?

Because PHP and MySql, both are open source and free to use. So someone has not to pay even a single panny for any kind for licence like oracle or sql server.

Someone has to buy a PHP hosting and nothing else and (s)he can start over with their ideas.

PHP have an extension for MySQL DBMS which is needless to setup a connectivity driver that will make a lot of conversions to achieve the query.

Plus on that, PHP & MySQL could be the worst combination if the developer didn't tuned the DB & PHP performance well, e.g. using Memcache, APC Accelerator, etc..

And PHP and MySQL isn;t the better combination, this depened on the type of application you are building, e.g. using MySQL for a real time application could be the worst unless a modification done on the MySQL backend, MongoDB & PHP would suit better for real time application, or Cassandra & PHP.

- Easy to learn and work with.- Open Source: You don't need to pay to develop with it.

- Very big Community, you find plenty of codes and resources to check online.- Support all data base servers and working with all web servers and platforms.- Flexible.

- Easy to access other services and communicate with.

- Lot of CMS and frameworks built on PHP and used like Drupal, YII, Joomla, Moodle, Wordpress, etc..

PHP support many databases, see this link of databases supported by it:

http://phplens.com/adodb/supported.databases.html

However MYSQL has this advantage since it go well with PHP, light weighted, you find lot of php functions that supported MYSQL, and common used by many people, CMS, and frameworks.

PHP and MySQL complement each other to do with neither can do alone. PHP can collect data, and MySQL can in turn store the information. PHP can create dynamic calculations, and MySQL can provide it with the variables it uses. PHP can create a shopping cart for your web store, but MySQL can then keep the data in a format PHP can use to create receipts on demand, show current order status, or even suggest other related products.

Although PHP and MySQL can each be used independently, when you put them together it opens up countless possibilities for your site. As the internet progresses, it becomes more and more necessary to deliver dynamic content to keep up with the demands of web surfers and their desire to have information instantly delivered to them online. By learning to use PHP and MySQL you can deliver this information to them on demand.

*Both are open source so less money

                                                                    -for development.

                                                                    -hosting.

                                                                    -Maintanance

*PHP is easy and light weight

*Joomla,wordpress etc makes development more easy.

*frameworks like codigniter and cakephp makes php more efficient.