Skip to content

Slot: Variable Column (variable_column)

For long orientation: name of the column that discriminates variables (e.g. variable). Not applicable to wide files.

Tier: conditionally_core

Why this slot matters

In a long file many variables share one value column and are told apart only by a discriminator column. Without naming that column, a consumer cannot separate this record's variable from every other variable in the file, so the value binding is ambiguous for all long-format data.

In plain terms

In a long table there is a column — often literally called variable — that says what each row measures (tmax, vp, ...). This slot names that column. Wide files do not have one, which is why this only applies to long orientation.

URI: envar:slot/variable_column

Applicable Classes

Name Description Modifies Slot
DataLayout How the companion data file (CSV / parquet) is laid out and how this record's... no

Properties

Type and Range

Property Value
Range String
Domain Of DataLayout

Cardinality and Requirements

Property Value

Examples

Value
variable

See Also

Identifier and Mapping Information

Annotations

property value
tier conditionally_core
justification In a long file many variables share one value column and are told apart only by a discriminator column. Without naming that column, a consumer cannot separate this record's variable from every other variable in the file, so the value binding is ambiguous for all long-format data.
explanation In a long table there is a column — often literally called variable — that says what each row measures (tmax, vp, ...). This slot names that column. Wide files do not have one, which is why this only applies to long orientation.

Schema Source

Mappings

Mapping Type Mapped Value
self envar:variable_column
native envar:variable_column

LinkML Source

name: variable_column
annotations:
  tier:
    tag: tier
    value: conditionally_core
  justification:
    tag: justification
    value: In a long file many variables share one value column and are told apart
      only by a discriminator column. Without naming that column, a consumer cannot
      separate this record's variable from every other variable in the file, so the
      value binding is ambiguous for all long-format data.
  explanation:
    tag: explanation
    value: In a long table there is a column — often literally called `variable` —
      that says what each row measures (`tmax`, `vp`, ...). This slot names that column.
      Wide files do not have one, which is why this only applies to long orientation.
description: 'For long orientation: name of the column that discriminates variables
  (e.g. `variable`). Not applicable to wide files.'
title: Variable Column
examples:
- value: variable
from_schema: https://w3id.org/linkml/microschemas/envar
see_also:
- https://doi.org/10.18637/jss.v059.i10
rank: 1000
domain_of:
- DataLayout
range: string