Mastering SAP ABAP

A complete guide to developing fast, durable, and maintainable ABAP programs in SAP

Paweł Grześkowiak, Wojciech Ciesielski, Wojciech Ćwik

• Publisher: Packt Publishing
• Year: 2019
• Print ISBN: 9781787288942
• eBook ISBN: 9781787129498
• Edition: 1
• Topic: Business
• Subtopic: Business Intelligence
• Index: Business

Take your SAP ABAP skills to the next level by mastering ABAP programming techniques with the help of real-world examples

Key Features

• Become adept at building interfaces and explore ABAP tools and techniques
• Discover the modern functionalities available in the latest version of ABAP
• Learn the process of creating stunning HTML5 applications using SAPUI5

Book Description

Advanced Business Application Programming (ABAP) is an established and complex programming language in the IT industry. This book is designed to help you use the latest ABAP techniques and apply legacy constructions using practical examples.

You'll start with a quick refresher on language and database concepts, followed by agile techniques for adding custom code to a modern ABAP system. After this, you will get up to speed with the complete ABAP toolset for importing data to and from different environments. Next, you'll learn how to print forms and work with the different ABAP tools for Extensible Markup Language (XML) manipulation. While covering further chapters, you'll gain insights into building stunning UI5 interfaces, in addition to learning how to develop simple apps using the Business Object Processing Framework (BOPF). You will also pick up the technique of handling exceptions and performing testing in ABAP. In the concluding chapters, you can look forward to grasping various techniques for optimizing the performance of programs using a variety of performance analysis tools.

By the end of this book, you will have the expertise you need to confidently build maintainable programs in Systems, Applications, and Products (SAP).

What you will learn

• Create stable and error-free ABAP programs
• Leverage new ABAP concepts including object-oriented programming(OOP) and Model-View-Controller (MVC)
• Learn to add custom code to your existing SAP program
• Speed up your ABAP programs by spotting bottlenecks
• Understand techniques such as performance tuning and optimization
• Develop modern and beautiful user interfaces (UIs) in an ABAP environment
• Build multiple classes with any nesting level

Who this book is for

This book is for developers who want to learn and use ABAP skills to become an industry expert. Familiarity with object-oriented programming concepts is expected.

Database Access in ABAP

Reading and operating on databases is one of the most frequently used skills for an Advanced Business Application Programming (ABAP) developer. A good understanding of the principles of ABAP OpenSQL is an essential skill that is required for operating in databases. To access the database in SAP, we can use two types of SQLs—ABAP OpenSQL and Native SQL. The main difference between these is that OpenSQL can be used in all database platforms to gain access to database tables declared in the ABAP Dictionary, while through Native SQL, you can use a database-specific SQL statement, which allows you to use a table that is not managed by the ABAP Dictionary. One of the biggest issues with Native SQL is the fact that a query written in Native SQL cannot be used in all databases and is specific to each type of database. In this chapter, we will be looking at OpenSQL only.

In this chapter, we will cover the following topics:

• Extracting data from the database in an efficient way
• Using an advanced function of SQL, for example, Subquery
• The ability to change or delete data on databases
• Optimizing queries

Technical requirements

All the code used in this chapter can be downloaded from the following GitHub link: https://github.com/PacktPublishing/Mastering-SAP-ABAP/tree/master/Chapter03.

Starting with OpenSQL

As ABAP was invented as a report language, it has a huge set of statements for accessing tables. ABAP was designed for high-performance database operations, but not for the definition or control of database tables. By definition, it's usually not the mission of the program to create or control database tables. However, those functionalities are included implicitly within the SAP system.

The section of ABAP that accesses the database tables is named OpenSQL and includes similar commands to standard SQL, such as SELECT, INSERT, UPDATE, and DELETE, which are known as data manipulation language (DML). The differences between standard SQL and OpenSQL include the fact that OpenSQL is platform independent and part of the ABAP language. This enables the syntax check to identify errors within the implementation of the SQL statement. Furthermore, there are several variants of the commands that are only for ABAP programs, which ease or accelerate the database accesses.

The platform-dependent SQL is generated by the database interface of the ABAP interpreter as part of the application server (AS) ABAP.

The data definition language (DDL), with all database-dependent commands such as CREATE, ALTER, and DROP, is given implicitly by the SAP Data Dictionary, as explained in Chapter 1, Creating Custom Code.

The DCL of standard SQL is not included in ABAP. Data consistency has to be guaranteed through the proper use of the concept of the SAP Logical Unit of Work (LUW) and the SAP concept of database locks.

In this chapter, we will see how the database tables can be accessed and manipulated, how several tables can be read at one time, and how huge amounts of data can be read with high performance. You will also learn about some obsolete statements, as well as the current recommendations and best practices for accessing data with high performance and optimized SQL statements.

When you access the database tables within an ABAP program, you always have to have an eye on performance. In development or consolidation systems, the amount of accessible data doesn't usually exceed a couple of thousands. The amount of the same data in productive systems can be measured even in millions (this amount can be even higher when it comes to the Internet of Things (IoT), big data, and the SAP High-Performance Analytic Appliance (HANA)).

You should think a little about performance while implementing database access, as the costs of implementing high-performance statements are insignificant in comparison to the costs of optimizing programs that are already productive.

Basics

In the first section, I'd like to present the most basic aspects of how to extract data from a database. In this subsection, we will explore how to create a basic select from table, as well as look at what components the SELECT statement is creating.

The SELECT statement is built from at least three mandatory parts. The first part in the SELECT statement is the resulting set. The resulting set is a list of fields that state what we want to get from the selected table. For the resulting set, we can use a list of fields directly entered in the statement, or we can use * to get all fields in the table. However, using * is not recommended due to performance issues, as we often do not need all fields in a table – only a few of them. The second part is a FROM statement, used to define which table we want to get the data from. The third part is INTO, which makes it possible to define which internal variable or variables input the data.

All examples presented in this chapter will be presented in SELECT from the sflight table. This SELECT statement will gradually be expanded by new capabilities.

The following is an ex...

Table of contents

• Title Page
• Copyright and Credits
• Dedication
• About Packt
• Contributors
• Preface
• Creating Custom Code
• The Basic Structure of ABAP
• Database Access in ABAP
• Import and Export to Document Formats
• Exposing Data to Print Forms
• ABAP and XML
• Building User Interfaces
• Creating Stunning UI5 Interfaces
• Business Object Processing Framework
• Modification and Customization Techniques
• Handling Exceptions in ABAP
• Testing ABAP programs
• Advanced Techniques in ABAP Objects
• Integrating SAP with Third-Party Systems
• The Background Processing of ABAP Programs
• Performance and Optimization of ABAP Code
• Assessments
• Another Book You May Enjoy