I really need of some knowledge about regular expression ,, as how to create own regex or rex ... so suggest me some tips to learn from the scratch for regular expression
The Field Extractor app on Splunkbase contains a regular expression reference which you can check if you hit the edit link on any of the extractions, which will give you examples and you could start by modifying them.
For more of a step by step tutorial, Zed Shaw's Learn Regex the Hard way is a great course to follow.
A reasonable reference exists in the Regular Expressions Info site, which has a quick start, tutorial and pages covering 'advanced' topics such as lookbehind.
There are some pretty good resources online.
Also you might want to grab a book. "Mastering Regular Expressions" is nice for instance: http://www.amazon.com/Mastering-Regular-Expressions-Jeffrey-Friedl/dp/0596528124/
RegExr is an awesome tool! I like it!
The Field Extractor app on Splunkbase contains a regular expression reference which you can check if you hit the edit link on any of the extractions, which will give you examples and you could start by modifying them.
For more of a step by step tutorial, Zed Shaw's Learn Regex the Hard way is a great course to follow.
A reasonable reference exists in the Regular Expressions Info site, which has a quick start, tutorial and pages covering 'advanced' topics such as lookbehind.