bach.DataFrame.get_all_variable_usage

get_all_variable_usage​

()

​[source]

Get all variables that influence the values of this DataFrame. This includes both variables that are used in the current self.series, but also variables that were used in earlier steps, i.e. in the SqlModels of self.base_node.

The output of this method can be useful for diagnosing issues with variables. If a variable is used multiple times, then it will appear here multiple times. If a variable has conflicting definitions then the conflicting dtypes and/or values are all returned.

Returned data

This method returns a list of DefinedVariable tuples, the fields in the tuples:

  • name: name of the variable
  • dtype: dtype
  • value: value that is currently set in self.variables, or None if there is no value
  • ref_path: If the variable is used in an already materialized part of the DataFrame, i.e. the usage is in self.base_node, then this is the reference path from self.base_node to the SqlModel in which the variable usage occurs. If the variable is used in self.series instead, then this is None
  • old_value: If the variable is used in an already materialized part of the DataFrame, then it also has a value already. That is this value. Will be None if this variable usage is not in self.base_node.

Returns​

List with all usages of variables in this DataFrame.

Return type​

List[bach.dataframe.DefinedVariable]