0019 Compare two values

Compare two values during transformation

This example shows how to compare two input values and populate an output column based on the result. Advanced ETL Processor can do this in several ways. The best option depends on the rule, the data volume, and whether the person maintaining it later should still like you.

Source data example

The source data contains values that need to be compared before the output column is populated.

Run the example

• Download and install Advanced ETL Processor [Link]
• Download and unzip the example [Link]
• Create a new transformation and open the .ats file.
• Double-click the Reader object and amend the source file path.
• Double-click the Writer objects and amend the target file path, leaving the calculation intact.
• Press the green arrow to run the transformation.

Transformation overview

The sample transformation demonstrates four ways to compare values. Using a calculation transformation is usually the slowest option, so use it when the rule needs calculation logic rather than a simpler comparison function.

Option 1: Compare Values transformation function

Use the Compare Values transformation function when the rule is a direct comparison between two fields.

Option 2: Calculation transformation

Use a calculation when the comparison needs extra logic. This is flexible, but normally slower than a dedicated transformation function.

Option 3: Lookup transformation

Use a lookup when the comparison depends on a reference table or a mapping list rather than only two values in the same row.

Option 4: If Equal To transformation function

Use the If Equal To transformation function when the logic only needs to check whether two values are the same.

More help

There are other ways to transform the data. Contact us if you need help choosing the right approach.

Visit ETL Tools Forum