A field mapping is created in a similar way to an entity mapping. Use the New button, select Field Mapping. Select or enter the target field.
There are two things you don't need to do on a field mapping:
- Data type conversion. The data hub will automatically convert compatible data types, for example extracting numbers from strings. There is therefore no data type selection on the field mapping.
- Reference change. You can set a different field reference in the field mapping. However, you can also do this in the entity mapping, so you wouldn't bother creating a field mapping just to change the reference of a field.
Field mappings are really just used for link and children fields.
For link fields, the field mapping allows you to select an entity mapping as the link entity. This means that you can resolve the link using source field names, rather than target field names. You can also set autocreate on the field mapping, though if it is set on the target field it will always be set on the source.
For children fields, the field mapping allows you to select an alternative source child entity. This allows you to manage child entities using source field names. You can also enter alternative names for the source parent identifier and source child sequence fields, though you are unlikely to need to do this because these are generated automatically rather than read from the source.
The field mapping can also be used to set that a field is mandatory in a particular context, though the interpretation of this will depend on the processing system.
If you have used a field mapping, link to these in place of the target fields in the entity mapping.