Advanced ETL Processor uses a Reader object to extract data from the source system before the rest of the transformation can do anything useful. Every transformation needs at least one Reader, because an ETL process with no input data is just a very confident empty diagram.
What You Will Learn
- Add and configure a Data Reader object.
- Understand how Readers extract data from different source types.
- Use Universal Data Reader behaviour when source formats match.
- Keep mappings stable when switching between compatible data sources.
Before You Start
Use a small sample source first. If the Reader cannot read five rows, it will not become philosophical and improve at five million.
Data Reader Docs
The Data Reader documentation explains how the Reader connects to the source and extracts data for the transformation.
Start with About Reader. Each transformation needs at least one Reader, and multiple Readers execute sequentially.
The Universal Data Reader section explains why compatible sources can share the same mapping. This is useful when text files, Excel files, and Access databases have the same field order, field names, and date or number formats.
For the full transformation flow, pair this page with the transformation screen overview, Reader Sources, and Writer docs.
Need Advanced ETL Processor First?
Download the Advanced ETL Processor trial before following the tutorial, or review Enterprise if you need scheduled unattended execution.