Hi Venkata,
As same as every language, ABAP also have the flow of learning from basic to advance. If you are studying for the certification, I hope you should have four different books in the following order.
- SAP/ABAP Basics
- ABAP Workbench Fundamentals
- Introduction to Dictionary
- Data Objects in ABAP Dictionary
- Performance when accessing Tables
- Input Checks
- Object Dependencies
- Changing Tables
- Views and Maintenance Dialogs
- Search Help
- Introduction to Screen Programming
- Program Interface
- Screen Elements for Input/Output
- Screen Elements: Subscreen and Tabstrip Controls
- OOABAP/ABAP Objects and Application Area
- Introduction to Object Oriented Programming
- Object Oriented concepts and Programming Techniques
- Object Oriented Repository Objects
- Exception Handling
- Shared Objects
- Dynamic Programming
- ABAP Objects and Application Area
- Changing SAP Standard System
- Enhancing Dictionary Elements
- Enhancing using Customer Exit
- Business Add-Ins
- Modifications
- Enhancements
- Webdynpro - Introduction
- Webdynpro - Controllers
- User Interface
- Controller and Context Programming
Regards
Rajkumar Narasimman