Skip to content

CSVW-EO Classes

CSVW-EO defines four main classes.

Class Purpose
csvw:Table Dataset-level metadata
csvw:Column Single-column metadata
csvw-eo:ColumnGroup Multi-column grouping metadata
csvw-eo:Partition Public partition definitions

Table

A csvw:Table represents the global dataset.

It contains:

  • table schema
  • privacy unit definition
  • global DP bounds

Example:

{
  "@type": "csvw:Table",
  "name": "penguins",
  "privacyUnit":"penguin_id",
  "maxContributions": 3,
  "maxLength": 1000,
  "tableSchema": {
    "columns": []
  },
  "additionalInformation": []
}

Column

A csvw:Column defines metadata for one column.

It may contain:

  • datatype
  • nullable proportion
  • public keys
  • grouping contribution assumptions
  • dependencies

Example: 

{
  "@type": "csvw:Column",
  "name": "species",
  "datatype": "string",
  "required": true,
  "privacyId": false,
  "keyValues":["Adelie", "Chinstrap", "Gentoo"],
  "exhaustiveKeys": true,
}

ColumnGroup

A csvw-eo:ColumnGroup describes grouping assumptions on multiple columns simultaneously.

Typical use cases:

  • (year, month)
  • (country, city)

It may contain:

  • public partitions
  • grouped contribution bounds
  • grouped public keys
"additionalInformation":[
  {
      "@type":"ColumnGroup",
      "columnsInGroup":[
        "species",
        "island"
      ],
      "partitions":[
        {
            "@type":"Partition",
            "predicate":{
              "species":{
                  "partitionValue":"Adelie"
              },
              "island":{
                  "partitionValue":"Biscoe"
              }
            },
            "maxLength":50, # of this partition
            "maxGroupsPerUnit":3,
            "maxContributions":1
        }
      ],
      "exhaustivePartitions": false,
      "maxLength":200, # of any partition of this ColumnGroup
  }
]

Partition

A csvw-eo:Partition defines a region of a value domain.

Examples:

  • one category
  • one month
  • one numerical interval

Partitions are indentified by predicates and may contain:

  • contribution bounds
  • public lengths

A csvw:Column or a csvw-eo:ColumnGroup can have a list of partitions in the field partition. If they are exhaustive then, exhaustivePartitions may be True.

Example:

Categorical column 

{
  "@type": "csvw-eo:Partition",
  "csvw-eo:predicate": {
    "partitionValue": "Biscoe"
  },
  "maxLength": 300,
  "maxGroupsPerUnit": 3,
  "maxContributions": 1
}

Continuous column 

{
  "@type": "csvw-eo:Partition",
  "csvw-eo:predicate": {
    "lowerBound": 100,
    "upperBound": 200,
  },
  "maxLength": 300,
  "maxGroupsPerUnit": 3,
  "maxContributions": 1
}

JSON-LD Structure

CSVW-EO extends standard CSVW JSON-LD structures with additional properties and objects. This image presents the base csvw json-ld structure on the left and the extended csvw-eo.

Overview