What is XML ?

XML: XML stands for extensible markup language.  This is designed to store the data and describing the data.

XML provides an environment where we can create cross platform compactable files.  Cross platform compatibility means, it is not specify to any operating system, software or hardware.

XML is standard set of rules, which is given by W3C. Which is used to create tag based data. XML is called mother language because using XML we can create our own markup languages. EX: MML, VML, WML, XHTML

Differences between XML and HTML

HTML

1.     HTML is used to create the web pages

2.       HTML contains predefined tags
3.       HTML tags not case sensitive
4.       HTML is an error free language  that means it will display the data or will not display the data on   browser
5.       HTML supports both proper nesting and in proper nesting
6.       HTML providing styles for the data

XML

1.       XML used to store and describe the data. 

2.       XML contains only user defined tags 

3.       XML tags are case sensitive 

4.       XML is not an error free language that means it will display the error information on the browser

5.       XML supports only proper nesting. 

6.       XML providing the structure for the data. 

Advantages

 

1. XML can also be used to  store the  data permanently like database
2. XML can be used configure web resources of any web based applications
3. XML files can also be used to given instruction to an electronic devices
4. Using XML we can also create our own markup language
5. XML can be used to transfer the data between un compactable languages

  

XML  Standard rules

1. Every XML document must contain exactly one root tag
2. Every XML tag must contain its starting tag and followed by its ending tag
3. XML tags must  follow the case sensitive
4. XML tags may contain child elements or attributes.
5. Attribute must be specified using “ “ (or)  ‘ ‘.
6. XML document must be nested
7. Element name can contain combination of alphabets and digits.
8. It must not begin with any digit.
9. It must not contain any spaces
10. It must not contain any special characters.

Most Common Useful MySql Queries.

At the time of MySql Query implementation, most of the time we are confusing rarely used queries. Below are the solutions for in real time scenario  MySql queries.

Get the parent Title:

SELECT *,(select vTitle from classifieds_categories c2 where c1.iParentId = c2.iId) as title FROM `classifieds_categories` c1

Get 2nd Height price:

SELECT max(vPrice) FROM `classifieds_list` where vPrice!= (SELECT max(vPrice) FROM `classifieds_list`);

Group wise latest records:

SELECT r1.* FROM `records` r1 Left join `records` r2 ON (r1.vGroup = r2.vGroup AND r2.iId > r1.iId) WHERE r2.iId IS NULL

Group wise first records:

SELECT r1.* FROM `records` r1 Left join `records` r2 ON (r1.vGroup = r2.vGroup AND r2.iId > r1.iId) WHERE r2.iId IS NULL

PHP Interview Questions Experienced

Regular PHP

1) Difference between PHP 4 & 5

2) Sessions & cookies

3) Diff Between MyIsam & INNODB Storage Engines

4) Left Join and Right Joins

5) Can you suggest any Query optimization techniques ?

6) Diff b/w Char & Varchar

7) Why use Enumeration Data type ?

8) How to use Fulltext ?

9) Connect & pConnect difference

10) Magic mathods __call, __set, __get, __constructss

11) Define vs Const vs Final

12) What are the error types in php

13) Why use ob_start()

14) What use Final Keyword ?

12) Why use and how to use Static methods ?

13) Abstract vs Interface

14) How to Call the parent constructor in side the constructor

15) What is the importance of __autoload ?

Codeigniter Framework

1) What is the different between Codeigniter 2 & Codeigniter 3

2) Explain Codeigniter Application Architecture ?

3) Can you explain Active Records ?

4) How to call the sessions ?

5) Diff B/W helpers and Libraries

6) How to call Multiple Database in Codeigniter ?

7) How to load the Languages ,libraries and helpers

8) What is the importance of Hooks ?

9) How to use joins in Codeigniter

10) How to implement the URL routing in codeigniter ?

11) How many ways to store the sessions in Codeigniter Application ?