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A Field is part of a RecordSet. It may represent a column of a table, or a nested data structure or even a nested RecordSet in the case of hierarchical data.

Field is a subclass of schema.org/Intangible.

Properties

Property	Expected Type	Cardinality	Description
source	DataSource URL	ONE	The data source of the field. This will generally reference a FileObject or FileSet’s contents
dataType	DataType	MANY	The data type of the field, identified by the URI of the corresponding class
repeated	Boolean	ONE	If true, then the Field is a list of values of type dataType
equivalentProperty	URL	MANY	A property that is equivalent to this Field
references	Reference	MANY	Another Field of another RecordSet that this field references (foreign key equivalent)
subField	Field	MANY	Another Field that is nested inside this one
parentField	Reference	MANY	A special case of SubField that should be hidden because it references a Field that already appears in the RecordSet

Key Features

• Each field has a name (unique identifier within the RecordSet)
• Supports foreign key relationships through the references property
• Supports hierarchical nesting with subField and parentField
• Can specify multiple data types for semantic enrichment

Examples

Simple Field

{
  "@type": "cr:Field",
  "@id": "ratings/user_id",
  "dataType": "sc:Integer",
  "source": {
    "fileObject": { "@id": "ratings-table" },
    "extract": {
      "column": "userId"
    }
  }
}

Field with Reference (Foreign Key)

{
  "@type": "cr:Field",
  "@id": "ratings/movie_id",
  "dataType": "sc:Integer",
  "source": {
    "fileObject": { "@id": "ratings-table" },
    "extract": {
      "column": "movieId"
    }
  },
  "references": {
    "@id": "movies/movie_id"
  }
}

Nested Field with SubFields

{
  "@type": "cr:Field",
  "@id": "gps_coordinates",
  "description": "GPS coordinates where the image was taken.",
  "dataType": "sc:GeoCoordinates",
  "subField": [
    {
      "@type": "cr:Field",
      "@id": "gps_coordinates/latitude",
      "dataType": "sc:Float",
      "source": {
        "fileObject": { "@id": "metadata" },
        "extract": { "column": "latitude" }
      }
    },
    {
      "@type": "cr:Field",
      "@id": "gps_coordinates/longitude",
      "dataType": "sc:Float",
      "source": {
        "fileObject": { "@id": "metadata" },
        "extract": { "column": "longitude" }
      }
    }
  ]
}

This example shows how fields can be hierarchically structured to represent complex data types like geographical coordinates.

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