Overview of Data Types

Cross-program (globally known) data types can be defined in the ABAP Dictionary. You can refer to these data types in every ABAP program in the SAP system with the TYPE addition for the corresponding ABAP statements.

 

On the ABAP Dictionary: Initial Screen, in the Data Type field, you can find the following basic types:

• Data element
• Structure
• Table type

 

 

Data Types in the ABAP Dictionary

You can use the type definitions shown in the figure, (with the exception of the domain) to define data objects in ABAP programs. The arrows show how the type definitions can be used together.

 

​Data elements use domains or integrated types to define their technical properties. However, an ABAP program cannot access domains to define data objects.

A structure consists of components that can be elementary fields, tables, and also structures.

 

The line type of a table type (ITAB) can be a structured type or an elementary type.

 

 

Domains

Domains manage the technical properties of data elements centrally. Domains cannot be used directly in programs, tables, and so on.

 

A Domain comprises the settings format and output characteristics

 

Format

The following are the most frequently used data types:

• CHAR

Fields of this type can have a maximum length of 255 characters in tables. To use longer character strings in tables, you have to choose the LCHR data type. In structures, there are no length restrictions regarding these fields.

 

• DATS

The length for this data type is set to 8 characters. You can define the output template with the user profile.

 

• DEC

A DEC field can have a maximum of 31 characters. This field is the calculation or amount field with decimal point, +/- sign, and thousands separators.

 

• NUMC

The length of NUMC field is restricted to a maximum of 255 characters. This characters' strings can only contain numbers.

 

Output characteristics

The maximum field length, including commas or decimal points, is specified for the input and output of values.

 

This value is usually calculated automatically once the number of characters has been assigned under format. However, you can overwrite it later. The output format affects how screens and selection screens are displayed. The specifications from this area are used when a field is integrated in a screen. However they can be modified by the screen painter.

 

You can also define a conversion routine. This conversion routine changes the display format when the content of a screen field is converted from the display format to the SAP-Internal format, and vice versa. The same conversion routine are executed by the system when you use the ABAP statement WRITE. Similarly, you can also use this conversion routine to override any unsuitable standard conversions.

 

For certain data types, such as DEC, FLTP, QUAN, and CURR, the check box +/- sign is ready for entry. If this is activated, the first character of the field is reserved for the +/- sign on a screen. Accordingly the system increases output length by 1.

 

For character-based data types, you should also determine whether lowercase letters are allowed. If the flag is not set, you can enter lowercase letter in the respective input fields; however, the lowercase letters are transformed into uppercase letters as soon as the user confirms the entry.

 

In addition, you can define valid value ranges that are used for input checks.

 

Data Elements

The semantic information is maintained in the field labels. These field labels can be displayed on screen or selection screens to explain the field content.

 

You also have to specify maximum length for the respective field label. If you work for a company that operates globally, you can translate the fields label into other languages. ( On the ABAP Dictionary: Initial screen, choose Goto -> Transition, or run the transaction code SE63 ).