Advanced ETL Processor uses lookup logic to replace or enrich input values from a mapping table. The mapping can be entered manually or loaded from a file or database, which is useful when codes, names, categories, or reference values must be standardised before writing the output. Lookups are where 'just translate these codes' usually turns into a small archaeology project.
What You Will Learn
- Use lookup logic inside a transformation.
- Substitute input values from a mapping table.
- Populate lookup mappings manually or from a file or database.
- Check input and output field mapping before running the transformation.
Before You Start
Use a small mapping table with known matches and misses. A lookup that only tests perfect values is mostly optimism wearing a data-quality hat.
Lookup Transformation Docs
The Lookup documentation explains how the transformation function substitutes values using a mapping table.
Use manually populated mapping tables when the reference list is small and stable. This is usually enough for short code lists, status values, or category names.
Use mapping tables loaded from a database or file when the lookup list is maintained elsewhere. For text-file mappings, set the line terminator correctly before using large files; the docs call this out because large-file hangs are not a debugging hobby anyone needs.
Pair this page with the Lookup Transformation Functions index and the main Transformer docs when building the full mapping flow.
Need Advanced ETL Processor First?
Download the Advanced ETL Processor trial before following the tutorial, or review Enterprise if you need scheduled unattended execution.