Variables & Datatypes

To define a variable in ABAP you can.

Declare Variables

Define Single Variable

Syntax: DATA (Variable_name) TYPE (DATA_Type) LENGTH(Length)

Note that Length is optional

DATA lv_name TYPE C LENGTH 20.
DATA lv_age TYPE I.
DATA meow TYPE STRING.

You can define multiple variables of same data type in one statement

DATA: lv_name  TYPE C LENGTH 20,
      lv_name2 TYPE C LENGTH 20,
      lv_name3 TYPE C LENGTH 20.

You can assign a value to a variable using

lv_name = 'Meooooow'.
meow = 'cat'.

You can also Define a variable with value in the same statement

DATA lv_name TYPE C LENGTH 15 VALUE 'Abdullah'.
DATA lv_age TYPE I VALUE 13.

Inline Declarations

You Can Define a variable with its value without assigning a type. ABAP will automatically infer its data type

Syntax: DATA(Variable_Name) = 15.

DATA(lv_age) = 15.

Primitive Data Types in ABAP

Type Keyword	Data Type Meaning	Example
C	Character (fixed length)	`DATA variable TYPE C LENGTH 10 VALUE 'Hello'.`
N	Numeric text (fixed length)	`DATA variable TYPE N LENGTH 5 VALUE '12345'.`
D	Date (YYYYMMDD)	`DATA variable TYPE D VALUE '20251016'.`
T	Time (HHMMSS)	`DATA variable TYPE T VALUE '143000'.`
I	Integer	`DATA variable TYPE I VALUE 15.`
INT8	8-byte Integer	`DATA variable TYPE INT8 VALUE 123456789.`
F	Floating point number	`DATA variable TYPE F VALUE '3.14'.`
P	Packed number (decimal)	`DATA variable TYPE P LENGTH 8 DECIMALS 2 VALUE '123.45'.`
X	Hexadecimal (fixed length)	`DATA variable TYPE X LENGTH 4 VALUE 'A1B2'.`
STRING	Dynamic character string	`DATA variable TYPE STRING VALUE 'Hello World'.`
XSTRING	Dynamic byte string	`DATA variable TYPE XSTRING VALUE '48656C6C6F'.`
DECFLOAT16	Decimal floating point 16	`DATA variable TYPE DECFLOAT16 VALUE '1.234567890123456'.`
DECFLOAT34	Decimal floating point 34	`DATA variable TYPE DECFLOAT34 VALUE '1.234567890123456789012345678901234'.`

Adding Comments

You can add comments in ABAP using * at the beginning of the line

* This is a comment
" This is also a comment
DATA lv_age TYPE I VALUE 15.  " This is an inline comment
DATA lv_name TYPE C LENGTH 20 VALUE 'Abdullah'.

Commenting Multiple Lines Shortcuts

You can highlight code and then press Shift + > to comment whole code.

You can press Shift + < to uncomment

Write Statements

You can write to the console using the WRITE statement

WRITE: 'Hello World'.

You can write multiple items in one statement

WRITE: 'Hello', 'World', '!' .

You can write variables

DATA(lv_name) = 'Abdullah'.
WRITE: 'Hello', lv_name, '!' .

You can write multiple lines using / before the item

WRITE: / 'Hello',
       / 'World',
       / '!'.

Conditional Blocks

IF Statement

Syntax: IF (condition). ... ENDIF.

DATA(lv_age) = 15.

IF lv_age > 18.
  WRITE: 'Adult'.
ENDIF.

IF-ELSE Statement

DATA(lv_age) = 15.

IF lv_age >= 18.
  WRITE: 'Adult'.
ELSE.
  WRITE: 'Minor'.
ENDIF.

IF-ELSEIF-ELSE Statement

DATA(lv_score) = 85.

IF lv_score >= 90.
  WRITE: 'Grade A'.
ELSEIF lv_score >= 80.
  WRITE: 'Grade B'.
ELSEIF lv_score >= 70.
  WRITE: 'Grade C'.
ELSE.
  WRITE: 'Grade F'.
ENDIF.

CASE Statement

Use CASE when you have multiple conditions based on same variable

DATA(lv_day) = 'Monday'.

CASE lv_day.
  WHEN 'Monday'.
    WRITE: 'Start of week'.
  WHEN 'Friday'.
    WRITE: 'Almost weekend'.
  WHEN 'Saturday' OR 'Sunday'.
    WRITE: 'Weekend'.
  WHEN OTHERS.
    WRITE: 'Midweek'.
ENDCASE.

Comparison Operators

Operator	Meaning	Example
`=` or `EQ`	Equal to	`IF lv_age = 18.`
`<>` or `NE`	Not equal	`IF lv_age <> 18.`
`>` or `GT`	Greater than	`IF lv_age > 18.`
`<` or `LT`	Less than	`IF lv_age < 18.`
`>=` or `GE`	Greater or equal	`IF lv_age >= 18.`
`<=` or `LE`	Less or equal	`IF lv_age <= 18.`

Logical Operators: AND, OR, NOT

Workareas & Internal Tables

Internal Table : Similar to SQL Table (stores multiple rows of data)
Work Area : Single row of data from internal table

Define Structure

First define the structure of your data

TYPES: BEGIN OF ty_student,
         id    TYPE I,
         name  TYPE STRING,
         age   TYPE I,
       END OF ty_student.

Define Work Area and Internal Table

DATA: wa_student TYPE ty_student,
      it_students TYPE TABLE OF ty_student.

Add Data to Internal Table

Using Work Area:

wa_student-id = 1.
wa_student-name = 'Abdullah'.
wa_student-age = 20.

APPEND wa_student TO it_students.

Read Data from Internal Table

Loop Through All Rows:

LOOP AT it_students INTO wa_student.
  WRITE: / wa_student-id, wa_student-name, wa_student-age.
ENDLOOP.

Debugging

We talked about debugging techniques. However, most of interactions needed GUI and i Don't have access to GUI now.

Will update it later with ScreenShots

info General Recommendations & Notes

Save & Format Regularly: Always save your work. Sessions can close anytime and un-saved work can be lost.
Use Comments: Comment your code for clarity, especially in complex logic.
Test Frequently: Run and test your code often to catch errors early.

Declare Variables​

Define Single Variable​

Adding Comments​

Write Statements​

Conditional Blocks​

IF Statement​

IF-ELSE Statement​

IF-ELSEIF-ELSE Statement​

CASE Statement​

Workareas & Internal Tables​

Define Structure​

Define Work Area and Internal Table​

Add Data to Internal Table​

Read Data from Internal Table​

Debugging​

info General Recommendations & Notes​