Introduction to ABAP4

1
Introduction to ABAP/4
2
What is ABAP/4?

• Advanced Business Application Program
• Release 4
• Why do we need to develop ABAP/4 applications in
  SAP R/3?

3
Why use ABAP?

• ABAP/4 is the programming language SAP developers
  use to build transactions and customize SAP R/3.
• The main purpose of ABAP/4 is to provide
  additional functionality to existing SAP
  applications.
• We tend not to use ABAP/4 to develop custom
  applications from scratch.

4
Purpose of ABAP/4

• The two most common uses of ABAP/4 are
• Producing custom reports
• Developing custom interfaces

5
Reports Interfaces

• Report - The ABAP program reads specific data
  from the SAP database and then displays this data
  on the screen or writes it to a printer.
• Interface - The ABAP program reads data from the
  SAP database and writes it to an external file to
  be used by another system (e.g. mainframe).

6
In this course we will?

• Learn enough ABAP/4 to access the SAP database
  using SQL.
• Write format this data to a printer / screen.
• Write this data to an external file
• SO YOU CAN
• Write a Report program
• Write an Interface program

7
How we will proceed

• We will learn various parts of an ABAP/4 program
  first.
• We will then put these parts together to develop
  a complete program.

8
Defining a program

• REPORT program name
• The report has various features to format output
  to the screen or printer we will talk about these
  features later.

9
Commenting your code

• It is expected that you will have sufficient
  comments in all the ABAP/4 programs you write.
  Why?
• It is EXPECTED of all PROFESSIONAL software
  developers.
• Due to the high turnover rate of SAP R/3 ABAP/4
  consultants, other people may be stuck
  maintaining your program.

10
Adding comments in ABAP/4

• 1 To comment an entire line use an asterisks
  ().
• This program will

11
Adding comments in ABAP

• 2 To comment part of a line use the double quote
  ()
• WRITE HELLO This statement will.

12
Variables and Constants

• We have given the program a name and added a
  description of the program in the comments.
• To manipulate and gather data for processing we
  need variables, records, and constants.

13
A variable is

• - A symbolic reference to a memory location that
  stores information temporarily. These variables
  persist only during the execution of the program,
  and the data they contain is lost when the
  execution is complete - unless the data is
  transferred to a database table or system file.

14
Variables

• MUST be declared before they are used.
• Can be declared anywhere in the program, BUT for
  consistency they should be declared at the
  beginning of a program or subroutine.
• Begin each variable with a letter and then a
  mixture of letters and numbers

15
Variables

• Use the underscore (_) to separate distinct
  words. DO NOT use the hyphen ( -) this has a
  special purpose that we will discuss later.
• NO reserved words (the same name as an ABAP
  command)

16
Variables

• Standard SCOPE rules apply. Variables defined at
  the program level are considered global,
  variables in subroutines are visible only to the
  subroutine.

17
Declaring variables

• DATA var(LENGTH) TYPE type DECIMALS number
  VALUE initial value
• var is the name of the variable
• (length) is the size of the variable

18

• TYPE is the type of variable. The possible data
  types for variables in ABAP are

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Data types for ABAP/4

• Type/Description/Example
• C Character hello world
• D Date 19990101
• F Floating point 3e4
• N Numeric text 10000
• P Packed Decimal 22.50
• T Time 104500
• H Hexadecimal 23A

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We will only use

• C, D, P, I, T, and maybe N.
• The DECIMAL is the number of decimal places for
  the packed decimal type.
• The size of the field digits before the decimal
  digits after the decimal.
• IF A FIELD HAS 6 DIGITS BEFORE THE DECIMAL AND 2
  DIGITS AFTER , IT MUST BE DECLARED AS A SIZE 8.
• VALUE is the initial or default value for the
  field at execution.

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Example 1

• Declare a variable that will hold the persons job
  title, it should be 10 characters in length and
  be initialize to MANAGER.
• DATA JOB_TITLE (10) TYPE C VALUE MANAGER.

22
Example 2

• Declare a variable to store the persons date of
  birth. Initialize the value to December 31, 1900.
• DATA DATE_OF_BIRTH (8) TYPE D VALUE 19901231.

23
Your turn

• Declare a variable that will store the employee
  income. It is comprised of 8 digits before the
  decimal point and 2 digits following it.
  Initialize the variable to 1 DOLLAR.

24
Answer

• DATA EMP_INCOME (10) TYPE P DECIMALS 2 VALUE
  1.00.

25
Constants

• Data that doesnt change its value during program
  execution.
• Defines the same as DATA variables.
• Example
• CONSTANTS PLANT_NUM TYPE I VALUE 6523.

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Run-time Parameters

• Allows us to pass data to the ABAP/4 program at
  run time.
• PARAMETERS parameter name TYPE type.
• For all the options see page 16 in the book.

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ABAP/4 Statements

• ABAP/4 does not care where a statement begins on
  a line. - As a result, you should indent sections
  of code for readability.

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ABAP/4 Statements

• Multiple statements can be placed on a single
  line. To improve readability this is not
  recommended.
• Blank lines can be placed anywhere in the program
  and should be used to improve readability.
• ALL ABAP/4 statements (except comments) must end
  with a period (.).

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Coding Statements

• We will now discuss how to display data
  including
• Moving data into a variable
• Moving data between variables
• Writing data to the report/screen
• Coding our first complete ABAP/4 program

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MOVE

• Move data into or between variables is done using
  the move statement. There are two forms of the
  move statement.
• MOVE value TO var
• var value

31
Moving data into a variable

• MOVE 10 TO PERSON_AGE.
• OR
• PERSON_AGE 10.

32
Moving data from one variable to another

• Move the contents of PERSON_AGE to DISPLAY_AGE
• MOVE PERSON_AGE TO DISPLAY_AGE
• or
• DISPLAY_AGE PERSON_AGE.

33
Computations

• COMPUTE var expression.
• ADD value TO var.
• SUBTRACT value FROM var.
• MULTIPLY value BY var.
• DIVIDE value BY var.

34
Outputting text

• To output data to the screen we use the write
  command.
• WRITE text.
• WRITE field name.

35
WRITE

• WRITE Boyle.
• WRITE LAST_NAME.