Input Options when Enabling Database Fields for Usage in SAP Fiori Apps

The following input options are available when enabling database fields for usage in SAP Fiori apps:

Table 1: Input Options to Enable Database Fields
Input Option	Description
Enabling Type	If your database field is only relevant for one database table and its corresponding business context, the default value Enable Field as New Custom Field is the right choice. If another database field with the same name and the same data element has already been enabled, the option Attach Field to Existing Custom Field is preselected and cannot be changed. Once you have attached this field to the existing one, both fields appear in the SAP Fiori app Custom Fields and Logic as one custom field which was added to different business contexts. If a business scenario is available in the SAP Fiori app which connects these business contexts, you can establish a data transfer from one database field to the other by enabling the usage of the fields in this business scenario. If another database field with a different name but the same data element has already been enabled, both options, Enable Field as New Custom Field and Attach Field to Existing Custom Field, are available. Tip If both fields have the same meaning and type of content, or even a data transfer has already been established between those fields, it is recommended to choose the option Attach Field to Existing Custom Field. If the fields are independent from each other, choose the option Enable Field as New Custom Field.
Custom Field ID	This is the unique identifier for the field in the SAP Fiori app Custom Fields and Logic. A proposal for this identifier is derived from the database field name, but you can overwrite this proposal using alphanumeric characters (also lower case letters) and underscores. If you add the field to business scenarios with the help of the app, the identifier will also be used as field name in the business contexts which did not contain your field before.
Semantic Type	This attribute defines the nature of the field content in general and how the field is to be displayed on an SAP Fiori UI. The semantic type corresponds to the field type in the SAP Fiori app Custom Fields and Logic. The offered types depend on the ABAP dictionary data type of the field. If the field domain contains fixed values or if the field refers to a check table, the default value for the semantic type is Code List. When you choose this type, a corresponding value help view is required. If the field domain is of the data type Character String, you can use fixed values to fill in the value help view. If the field is of a numeric data type, you need to fill in the value help view manually and provide the required information such as the check table of the field. If the ABAP dictionary data type has a clearly defined purpose like to display a date or time, its semantic type is set accordingly and cannot be changed.
Value Help View	If the semantic type of your field is Code List, Currency, Language or Unit of Measure, a value help view is required to retrieve the fixed values which are stored in the field domain directly or in a referenced value table. This view is used as soon as the field is added, for example, to SAP Fiori UIs and reports using the SAP Fiori app Custom Fields and Logic. If available, the system proposes a standard value help view like I_LANGUAGE for the semantic type Language. If not available, or if the standard view does not fit to your needs, you can create templates for such a view and its corresponding text view by clicking Generate. Copy these templates to new Core Data Services (CDS) Data Definitions in ABAP Development Tools for SAP NetWeaver (ADT) and replace the variables in angle brackets with suitable values. You may change the data sources or apply `WHERE` conditions to the views to restrict the allowed values. Caution Aliases, associations and annotations must not be changed.
Package and Request	Upon confirmation of the dialog by pressing `F8`, you are prompted to enter a package and a transport request for the objects which are being created by the system to enable your field for the SAP Fiori app Custom Fields and Logic. Make sure that these objects (including any newly created value help views) are kept in the same software component like the append structure with the database field itself, and that they are always transported together.