Settype Transform

Sets the data type of the specified column or columns. The column data is validated against the new data type, which can change the results of column profiling.Type is specified as a string literal or comma-separated set of literals. For more information on valid string literals, see Valid Data Type Strings.

Tips:

  • When a column is set to a data type, all values in the column are validated against the new type, which might change the number of mismatched values. Some cleanup might be required. Some operations might cause the data type to be re-validated automatically.
  • It might be easier to set type using the column's drop-down. Selections of data type from the column drop-down are turned into recipe steps using the settype transform.
  • If you encounter a significant number of mismatches after you change the data type, you might find it helpful to change or revert the type to String. All data can be interpreted as a String or a list of string values. The transforms and functions for manipulating String data might be easier to use to clean up mismatched data before changing the data type to the preferred one.
  • In the Transform Builder, remove any values from the type parameter between the single quotes to see accepted values to enter for the available column data types.
  • Row values that do not match the new data type might be turned to null values during job execution.

Basic Usage

Single-column example:

settype col: Score type: 'Integer'

Output: Changes the data type for the Score column to Integer.

Multi-column example:

settype col: Score,studentId type: 'Integer'

Output: Changes the data type for the Score and studentId columns to Integer.

Parameters

settype col:col1,col2 type:'string_literal'

TokenRequired?Transform BuilderData TypeDescription
settypeYChange column typetransformName of the transform
colYColumnstringComma-separated list of columns to which to apply the specified type.
typeYNew typestringString literal identifying the data type to apply to the column(s). See Valid Data Type Strings.

For more information on syntax standards, see Language Documentation Syntax Notes.

col

Identifies the column(s) to which to apply the transform. You can specify one or more columns.

Usage Notes:

Required?Data Type
YesComma-separated strings (column name or names)

type

Defines the data type that is to be applied to the transform. Type is defined as a String literal. For a list of valid strings, see Valid Data Type Strings.

settype col: zips type:'Zipcode'

Output: Changes the data type of the zips column to Zip Code data type. All values are validated as U.S. Zip code.

Usage Notes:

Required?Data Type
YesString value

Examples

Example - Simple settype with date values

Source:

Here is a list of activities listed by date. Note the variation in date values, including what is clearly an invalid date. Here is the source data:

myDate, myAction
4/4/2016,Woke up at 6:30
4-4-2016,Got ready
9-9-9999,Drove kids to school
4-4-2016, Commuted to work

Transform:

When this data is imported into the Transformer page, there are couple of immediate issues: no column headings and blank rows at the bottom. These two transforms fix that:

header

delete row: ISMISSING([myDate])

For the invalid date, you can infer from the rows around it that it should be from the same date. You can make the following change to fix it:

replace col: myDate on: `9-9-9999` with: '4-4-2016' global: true

Now that the dates look fairly consistent, you can set the data type of the column to a matching Datetime format:

settype col: myDate type: 'Datetime','mm-dd-yy','mm*dd*yyyy'

Note the syntax above for specifying Datetime types. In addition to the Datetime keyword, you must specify the format type, followed by the variation of that format.

Tip: A set of supported formats and variations for Datetime are available through the column data type selector. When you select your desired Datetime format, the setttype transform is added to your recipe.

Results:

myDatemyAction
4/4/2016Woke up at 6:30
4-4-2016Got ready
4-4-2016Drove kids to school
4-4-2016Commuted to work

Example - Use merge and settype to clean up numeric data that should be treated as other data types

This example illustrates how to clean up data that has been interpreted as numeric in nature, when it is actually String or a structured string type, such as Gender. This example uses:

Source:

The following example contains customer ID and Zip code information in two columns. When this data is loaded into the Transformer page, it is initially interpreted as numeric, since it contains all numerals.

The four-digit ZipCode values should have five digits, with a 0 in front.

CustIdZipCode
40201231234
201212194105
321201294101
13012122020

Transform:

CustId column: This column needs to be retyped as String values. You can set the column data type to String through the column drop-down, which is rendered as the following transform:

settype col:CustId type:'String'

While the column is now of String type, future transforms might cause it to be re-inferred as Integer values. To protect against this possibility, you might want to add a marker at the front of the string. This marker should be removed prior to execution.

The basic method is to create a new column containing the customer ID marker (C) and then merge this column and the existing CustId column together. It's useful to add such an indicator to the front in case the customer identifier is a numeric value that could be confused with other numeric values. Also, this merge step forces the value to be interpreted as a String value, which is more appropriate for an identifier.

merge col:'C', CustId

You can now drop the CustId columns and rename the new column as CustId.

ZipCode column: This column needs to be converted to valid Zip Code values. For ease of use, this column should be of type String:

settype col:ZipCode type:'Zipcode'

The transform below changes the value in the ZipCode column if the length of the value is four in any row. The new value is the original value prepended with the numeral 0:

set col: ZipCode value: if(len($col) == 4, merge(['0',$col]), $col)

This column might now be re-typed as Zipcode type.

Results:

CustIdZipCode
C402012301234
C201212194105
C321201294101
C130121202020

Remember to remove the C marker from the CustId column. Select the C value in the CustId column and choose the replace transform. You might need to re-type the cleaned data as String data.

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