Returns the nature of the variable as a Text value. The nature indicates the kind of summary statistics that can be performed on values. Nature values are:

  • CATEGORICAL: the values of the variable are discrete and described by the categories of the variable or the value type is boolean,
  • CONTINUOUS: values can be any in the considered value type (applies also to variables having categories that are all flagged as being missing),
  • TEMPORAL: value of type date or datetime,
  • GEO: value of type point, linestring or polygone,
  • BINARY: value of type binary,
  • UNDETERMINED when non of the above apply.

See also $var, $variable.