Fixed values and value table in a domain are helpful for values entry restrictions when we save data to database & input help (F4) i.e. program with screens/selection screen using fields with such domains can provide users with the options to select values. Note: There are multiple ways available in SAP to provide input help.
Domains provide 3 options:
1. Fixed values ( Single Vals. )
When we have limited values, we can use the fixed values. This restrict applications/users to save only available fixed values for the field to database. Values other than fixed values will result in error while saving data.
An input help is automatically made available for field or screen field using this domain. In the below example, domain VBTYP has fixed values. When this domain is referenced via a data element VBTYP in the screen, input help ( F4 ) option is automatically available.
Additions to the fixed values provided by SAP can be implemented using Fixed Value Append.
2. Intervals
Intervals restrict applications/users to save data only within the given range to database. Values outside range will result in error while saving data.
This option can be used to provide range of values as input help. This option is rarely used in SAP applications. In below example, we have different ranges for different customer account types.
Additions to the intervals provided by SAP can be implemented using Fixed Value Append.
3. Value Table
When we have more number of entries to be displayed as F4 help or for value restriction for database, we can use value table. Its entries will be displayed as input help when value table will act as check table. When foreign key relationship is established between value table and table using domain that has value table, value table becomes a check table. Due to foreign key referential integrity, database will not allow values other then check table. Click here to understand more about foreign key relationship.
In example below, Country key field is created on selection screen with reference to KNA1-LAND1. There is a foreign key relationship between KNA1-LAND1 and value table T005. As a result, input help option is available for this field.