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Wrangle enables you to specify sets of columns using discrete values, ranges, and wildcards. This section describes the syntax associated with these various types of references.

Column references can fit into the following categories:

CategoryDescription
SingleA reference to a single column.
MultipleReferences to multiple discrete columns.
AllA single reference to all columns in the dataset.
RangeReferences to a set of consecutive columns in the dataset.
AdvancedAny of the above categories or combinations of them.

Tip: The easiest way to specify columns in your transformations is to build them through the Transform Builder, where you can quickly select the category of column reference from the Columns drop-down in select transformations. For more information, see Transform Builder.

The sections below describe how to specify the above categories of column references in raw  Wrangle

Single and Multiple Columns

You can specify single and multiple columns by inserting discrete references to the column name.

Single column:

Insert the column name in the Columns textbox:

myColumn

Example transformation:

Transformation Name Move Columns
Parameter: Column(s) Multiple
Parameter: Column myColumn
Parameter: Option Before
Parameter: Column myFirstColumn

Multiple columns:

You can reference multiple discrete columns using comma-separated values:

myColumn, myOtherColumn

Example transformation:

Transformation Name Move Columns
Parameter: Column(s) Multiple
Parameter: Column myColumn,myOtherColumn
Parameter: Option Before
Parameter: Column myFirstColumn

All Columns

If needed, you can specify all columns in the dataset using a wildcard. The asterisk character (*) is used to indicate all columns in the dataset:

*

Example transformation:

Transformation Name Edit column with formula
Parameter: Column(s) Advanced
Parameter: Column *
Parameter: Formula set col: * value: average(myCol)

The above transformation sets the values for all columns to be the AVERAGE value of the myCol column.

Column Ranges

You can use the tilde character (~) to express a range of columns between the start column and the end column, inclusive: 

myStartColumn~myEndColumn

NOTE: If a transformation step is inserted before this one in which the location of one of the columns in the range is changed, then the columns represented by the specified range changes. If the column is no longer present, then this transformation step must be fixed.

Example transformation:

Transformation Name Move Columns
Parameter: Column(s) Advanced
Parameter: Column myStartColumn~myEndColumn
Parameter: Option Before
Parameter: Column myFirstColumn

Advanced Column References

You can use advanced column references to express combinations of the above types of column reference categories. 

myStartColumn~myEndColumn, thisColumn2, thisColumn3

The above example references:

  • The range of columns between myStartColumn and myEndColumn, inclusive
  • The thisColumn2 column
  • The thisColumn3 column

Example transformation:

Transformation Name Edit column with formula
Parameter: Column(s) Advanced
Parameter: Column myStartColumn~myEndColumn, thisColumn2, thisColumn3
Parameter: Formula POW($col,2)

For more information on the $col reference, see below.

Column Variable References

When you are applying a transformation step to multiple columns, you cannot reference each column as a parameter in any function in the transformation. Instead, you can insert a variable reference into the function. Below is an example column variable reference used as the input parameter for the SUM function:

SUM($col)

As the transformation is applied to each column in your column set, the $col reference is replaced with the name of the column.

For more information, see Source Metadata References.

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