Changes to the Language

The following changes have been applied to  Wrangle in this release of Designer Cloud Enterprise Edition.

Release 6.4

Improvements to metadata references

Broader support for metadata references: For Excel files, $filepath references now return the location of the source Excel file. Sheet names are appended to the end of the reference. See Source Metadata References.

Release 6.3

New Functions

Optional input formats for DateFormat task

The DateFormat task now supports a new parameter: Input Formats. This parameter specifies the date format to use when attempting to parse the input column.

• If the parameter is specified, then the value of the parameter is used to parse the inputs. 

• (default) if the parameter is not specified, then the following common formats are used for parsing the input:

  'M/d/yy',
  'MM/dd/yy',
  'MM-dd-yy',
  'M-d-yy',
  'MMM d, yyyy',
  'MMMM d, yyyy',
  'EEEE, MMMM d, yyyy',
  'MMM d yyyy',
  'MMMM d yyyy',
  'MM-dd-yyyy',
  'M-d-yyyy',
  'yyyy-MM-ddXXX',
  'dd/MM/yyyy',
  'd/M/yyyy',
  'MM/dd/yyyy',
  'M/d/yyyy',
  'yyyy/M/d',
  'M/d/yy h:mm a',
  'MM/dd/yy h:mm a',
  'MM-dd-yy h:mm a',
  'MMM dd yyyy HH.MM.SS xxx',
  'M-d-yy h:mm a',
  'MMM d, yyyy h:mm:ss a',
  'EEEE, MMMM d, yyyy h:mm:ss a X',
  'EEE MMM dd HH:mm:ss X yyyy',
  'EEE, d MMM yyyy HH:mm:ss X',
  'd MMM yyyy HH:mm:ss X',
  'MM-dd-yyyy h:mm:ss a',
  'M-d-yyyy h:mm:ss a',
  'yyyy-MM-dd h:mm:ss a',
  'yyyy-M-d h:mm:ss a',
  'yyyy-MM-dd HH:mm:ss.S',
  'dd/MM/yyyy h:mm:ss a',
  'd/M/yyyy h:mm:ss a',
  'MM/dd/yyyy h:mm:ss a',
  'M/d/yyyy h:mm:ss a',
  'MM/dd/yy h:mm:ss a',
  'MM/dd/yy H:mm:ss',
  'M/d/yy H:mm:ss',
  'dd/MM/yyyy h:mm a',
  'd/M/yyyy h:mm a',
  'MM/dd/yyyy h:mm a',
  'M/d/yyyy h:mm a',
  'MM-dd-yy h:mm:ss a',
  'M-d-yy h:mm:ss a',
  'MM-dd-yyyy h:mm a',
  'M-d-yyyy h:mm a',
  'yyyy-MM-dd h:mm a',
  'yyyy-M-d h:mm a',
  'MMM.dd.yyyy',
  'd/MMM/yyyy H:mm:ss X',
  'dd/MMM/yy h:mm a',

  These formats are a subset of the date formatting strings supported by the product. For more information, see Datetime Data Type.

Release 6.2

New Functions

ARRAYELEMENTAT function accepts new inputs

In previous releases, the ARRAYELEMENTAT function accepted a second input parameter to specify the index value of the element to retrieve. This "at" parameter had to be an Integer literal.

Beginning in this release, the function also accepts for this second "at" parameter:

• Names of columns containing Integer values
• Functions that return Integer values

For more information, see ARRAYELEMENTAT Function.

Release 6.1

None.

Release 6.0

New Functions

Changes to LIST* inputs

The following LIST-based functions have been changed to narrow the accepted input data types. In previous releases, any data type was accepted for input, which was not valid for most data types. 

In Release 6.0 and later, these functions accept only Array inputs. Inputs can be Array literals, a column of Arrays, or a function returning Arrays.

Renamed functions

The following functions have been renamed in Release 6.0.

FILL Function has new before and after parameters

Prior to Release 6.0, the FILL function replaced empty cells with the most recent non-empty value. 

In Release 6.0, before and after function parameters have been added. These parameters define the window of rows before and after the row being tested to search for non-empty values. Within this window, the most recent non-empty value is used. 

The default values for these parameters are -1 and 0 respectively, which performs a search of an unlimited number of preceding rows for a non-empty value.

For more information, see FILL Function.

Release 5.9

New functions

The following functions can now be applied directly to arrays to derive meaningful statistics about them. 

Release 5.8

File lineage information using source metadata references

Beginning in Release 5.8, you can insert the following references into the formulas of your transformations. These source metadata references enable you to continue to track file lineage information from within your datasets as part of your wrangling project.

 For more information, see Source Metadata References.

New math and statistical functions for arrays

The following functions can now be applied directly to arrays to derive meaningful statistics about them. 

Release 5.7

WEEKNUM function now behaves consistently across running environments

In Release 5.6 and earlier, the WEEKNUM function treated the first week of the year differently between the Trifacta Photon and Spark running environments:

• Trifacta Photon week 1 of the year: The week that contains January 1.
• Spark week 1 of the year: The week that contains at least four days in the specified year.

This issue was caused by Spark following an ISO-8601 standard and relying on the joda datetimeformatter. 

Beginning in Release 5.7, the WEEKNUM function behaves consistently for both Trifacta Photon and Spark:

• Week 1 of the year: The week that contains January 1.

For more information, see WEEKNUM Function.

Release 5.6

URLPARAMS function returns null values

In Release 5.1 and earlier, the URLPARAMS function returned empty Objects when no answer was computed for the function. 

In Release 5.6 and later, this function returns null values in the above case.

See URLPARAMS Function.

Release 5.1

Wrangle now supports nested expressions

Beginning in Release 5.1, all  Wrangle functions now supported nested expressions, which can be arithmetic calculations, column references, or other function calls.

The following expression is a valid transform in  Wrangle. It locates the substring in myString that begins with the @ sign until the end of the string, inclusive:

derive value: substring(myString, find(myString, '@', true, 0), length(myString)

Nested arithmetic expressions:

Suppose you wanted just the value after the @ sign until the end of the string. Prior to Release 5.1, the following generated a validation error:

derive value: substring(myString, find(myString, '@', true, 0) + 1, length(myString)

In the above, the addition of +1 to the second parameter is a nested expression and was not supported. Instead, you had to use multiple steps to generate the string value. 

Beginning in Release 5.1, the above single-step transform is supported.

Nested column references:

In addition to arithmetic expressions, you can nested column references. In the following example, the previous step has been modified to replace the static +1 with a reference to a column containing the appropriate value (at_sign_offset) : 

derive value: substring(myString, find(myString, '@', true, 0) + at_sign_offset, length(myString)

Nested function references:

Now, you can combine multiple function references into a single computation. The following computes the total volume of a cube of length side and then multiplies that volume by the number of cubes (cube_count) to compute the total cube_volume

derive type: single value: MULTIPLY(POW(cube_side,3),cube_count) as: 'cube_volume'

For more information, see Wrangle Language.

SOURCEROWNUMBER function generates null values consistently

The SOURCEROWNUMBER function returns the row number of the row as it appears in the original dataset. After some operations, such as unions, joins, and aggregations, this row information is no longer available.

In Release 5.0.1 and earlier, the results were confusing. When source row information was not available, the function was simply not available for use.

In Release 5.1 and later, the behavior of the SOURCEROWNUMBER function is more consistent:

• If the source row information is available, it is returned.
• If it is not available:
  • The function can still be used.
  • The function returns null values in all cases.

For more information, see SOURCEROWNUMBER Function.

New Functions

Release 5.0.1

RAND function generates true random numbers

In Release 5.0 and earlier, the RAND function produced the same set of random numbers within the browser, after browser refresh, and over subsequent runs of a job. 

• During job execution, a default seed value was inserted as the basis for the function during the execution of the job. 
• In some cases, this behavior is desired. 

In Release 5.0.1 and later, the RAND function accepts an optional integer as a parameter. When this new seed value is inserted, the function generates deterministic, pseudo-random values.

• This version matches the behavior of the old function.

  NOTE: On all upgraded instances of the platform, references to the RAND function have been converted to use a default seed value, so that previous behavior is maintained in the upgraded version.

• If no seed value is inserted as a parameter, the RAND function generates true random values within the browser, after browser refresh, and over subsequent job runs.

  NOTE: Be aware that modifying your dataset based on the generated values of RAND() may have unpredictable effects later in your recipe and downstream of it.

For more information, see RAND Function.

Release 5.0

Required type parameter

Prior to Release 5.0, the following was a valid  Wrangle step:

derive value:colA + colB as:'colC'

Beginning in Release 5.0, the type parameter is required. This parameter defines whether the transform is a single or multi-row formula. In the Transform Builder, this value must be specified.

The following is valid in Release 5.0:

derive type:single value:colA + colB as:'colC'

See Derive Transform.

See Transform Builder.

Deprecated aggregate transform

In Release 4.2.1 and earlier, the aggregate transform could be used to aggregate your datasets using aggregation functions and groupings. 

In Release 5.0 and later, this transform has been merged into the pivot transform. The aggregate transform has been deprecated and is no longer available. 

Example 1

Release 4.2.1 and earlier Aggregate:

aggregate value:AVERAGE(Scores)

Release 5.0 and later Pivot:

pivot value: AVERAGE(Score) limit: 1

The limit parameter defines the maximum number of columns that can be generated by the pivot.

Example 2

Aggregate:

aggregate value:AVERAGE(Scores) group:studentId

Pivot:

pivot group: StudentId value: AVERAGE(Score) limit: 1

For more information, see Pivot Transform.

New search terms

In the new Search panel, you can search for terms that can be used to select transformations for quick population of parameters. In the following table, you can see  Wrangle how terminology has changed in Release 5.0 for some common transforms from earlier release. 

Support for <> operator

Prior to Release 5.0, the following operator was used to test "not equal" comparisons:

!=

Beginning in Release 5.0, the following operators is also supported:

<>

Example:

derive value:IF ((col1 <> col2), 'different','equal') as:'testNotEqual'

For more information, see Comparison Operators.

ROUND function takes optional number of digits

The ROUND function now supports rounding to a specified number of digits. By default, values are rounded to the nearest integer, as before. See ROUND Function.

New Functions

Release 4.2.1

None.

Release 4.2

New Filter transform

Perform a variety of predefined row filtrations using the new filter transform, or apply your own custom formula to keep or delete rows from your dataset. 

• See Remove Data.
• See Filter Transform. 

New Case transform

Beginning in Release 4.2, you can use the Transform Builder to simplify the construction of CASE statements. For each case, specify the conditional and resulting expression in separate textboxes.

• See Apply Conditional Transformations.
• See Case Transform. 

Rename transform now supports multi-column rename

Use the rename transform to rename multiple columns in a single transform. 

• See Rename Columns.
• See Rename Transform.

Drop specified columns or drop the others

The drop transform now supports the option of dropping all columns except the ones specified in the transform. See Drop Transform.

New string comparison functions

Compare two strings using Latin collation settings. See below.

NOW function returns 24-hour time values

In Release 4.1.1 and earlier, the NOW function returned time values for the specified time zone in 12-hour time, which was confusing.

In Release 4.2 and later, this function returns values in 24-hour time. 

New Transforms

New Functions