increment

Introduction

Use the increment instruction to sort a data extract based on given column names and a column containing numerical values. Once sorted, a new column is added to the data extract containing the numerical difference between the value in the current row and the value in the previous row.

This transformation is similar to the sumup transformation. The increment transformation calculates the difference between rows and the sumup transformation calculates the sum total of rows.

Creating a custom script transformation using the increment instruction

To create and configure a custom script using the increment instruction, follow these steps:

1. Create a custom script transformation.

2. In the Instruction step, select the increment instruction.

3. To configure the custom script instruction, fill in the required fields below, as well as any optional fields you require:

Input Field

Enter the name of the column that contains the numeric values for which the transformation will calculate the difference.

Output Field

Enter the name of the new column that you want to contain the calculated differences.

Keys

Enter the names of one or more columns that you want to use to sort the data. Every new unique combination of Key fields will reset the difference calculation to 0.

If you do not enter any column names in this field, your data will not be sorted. The rows will stay in the order in which they were fetched from your data source.

Subtable

Enter the name for a subtable that you want to use within this custom script.

A subtable is a temporary table that only exists for this custom script. You can apply additional instructions within the same custom script to the subtable. However, the subtable cannot be used in any other custom scripts.

If a subtable does not exist for the current custom script, the transformation is applied to the data extract, and the enriched data is output into the subtable. If the subtable already exists for the custom script, the subtable is used as the input for the transformation and optionally as the output.

Example