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Excerpt

Generate a new column where the values are the output of the value expression. Expression can be calculated based on values specified in the group parameter. Output column can be named as needed.  

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snippetBasic

String literal example:

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derive value: 'passed' as:'status'

Output: Generates a new column called status, each row of which contains passed for its value. 

Column reference example:

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derive value:productName as:'orig_productName'

Output: Generates a new column called orig_productName, which contains all of the values in productName, effectively serving as a backup of the source column.

Function reference example:

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derive value:SQRT(POW(a,2) + POW(b,2)) as:'c'

Output: Generates a new column called c, which is the calculation of the Pythagorean theorem for the values stored in a and b. For more information on this example, see POW Function.

Window function example:

You can use window functions in your derive transforms:

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derive col: avgRolling value: ROLLINGAVERAGE(POS_Sales, 7, 0) group: saleDate order: saleDate

Output: Calculate the value in the column of avgRolling to be the rolling average of the POS_Sales values for the preceding seven days, grouped and ordered by the saleDate column. For more information, see Window Functions.

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snippetParameters
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derive value:(expression) [order: order_col] [group: group_col] [as:'new_column_name']

ParameterRequired?Transform BuilderData TypeDescription
valueYFormulastringExpression that generates the value to store in the new column
orderNOrder bystringColumn or column names by which to sort the dataset before the value expression is applied
groupNGroup bystringIf you are using aggregate or window functions, you can specify a group expression to identify the subset of records to apply the value expression.
asNNew column namestringName of the newly generated column

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value

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value Parameter
value Parameter

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snippetusage

Required?Data Type
YesString (literal, column reference, function call, or combination)

order

This parameter specifies the column on which to sort the dataset before applying the specified function. For combination sort keys, you can add multiple comma-separated columns.

Info

NOTE: If it is present, the dataset is first grouped by the group value before it is ordered by the values in the order column.

Info

NOTE: The order column does not need to be sorted before the transform is executed on it.

Tip

Tip: To sort in reverse order, prepend the column name with a dash (-MyDate).

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snippetusage

Required?Data Type
NoString (column name)

group

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group Parameter
group Parameter

The ProdId column contains three values: P001P002, and P003, and you add the following transform:

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derive value:SUM(Sales) group:ProdId as:'SalesByProd'

The above transform generates the SalesByProd column, which contains the sum of the Sales values, as grouped according to the three product identifiers.

If the value parameter contains aggregate or window functions, you can apply the group parameter to specify subsets of records across which the value computation is applied. 

You can specify one or more columns by which to group using comma-separated column references.

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snippetusage

Required?Data Type
NoString (column name)

as

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as Parameter
as Parameter

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derive value:(colX * colY) as:'areaXY'

Output: Generates a new column containing the product of the values in columns colX and colY. New column is explicitly named, areaXY.

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snippetusage

Required?Data Type
NoString (column name)

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snippetExamples

Example - Basic Derive Examples

The following dataset is used for performing some simple statistical analysis using the derive transform.

Source:

StudentIdTestNumberTestScore
S001178
S001285
S001381
S002184
S002292
S002377
S003183
S003288
S003385

Transform:

First, you can calculate the total average score across all tests:

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derive value:AVERAGE(Score) as:'avgScore'

In their unformatted form, the output values are lengthy. You can edit the above transform to nest the value statement with proper formatting using the NUMFORMAT function:

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derive value:NUMFORMAT(AVERAGE(Score),'##.00') as:'avgScore'

You might also be interested to know how individual students fared and to identify which tests caused the greatest challenges for the students:

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derive value: NUMFORMAT(AVERAGE(Score),'##.00') group: StudentId as: 'avgScorebyStudentId'

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derive value:NUMFORMAT(AVERAGE(Score),'##.00') group:TestNumber as:'avgScoreByTest'

To calculate total scores for each student, add the following. Since each individual test score is a whole number, no rounding formatting is required.

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derive value:SUM(Score) group:StudentId as:'totalScoreByStudentId'

Results:

StudentIdTestNumberTestScoreavgScoreavgScorebyStudentIdScoreByTesttotalScoreByStudentId
S00117883.6781.3381.67244
S00128583.6781.3388.33244
S00138183.6781.3381.00244
S00218483.6784.3381.67253
S00229283.6784.3388.33253
S00237783.6784.3381.00253
S00318383.6785.3381.67256
S00328883.6785.3388.33256
S00338583.6785.3381.00256

 

Example - Rounding Functions

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EXAMPLE - Rounding Functions
EXAMPLE - Rounding Functions

Example - Other Examples

In the language documentation, there are many other examples where the derive transform is used. 

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