Data Transformation / Migration:

Data transformation is the process of converting data from one format (e.g. a database file, XML document, or Excel sheet) to another. Because data often resides in different locations and formats across the enterprise, data transformation is necessary to ensure data from one application or database is intelligible to other applications and databases, a critical feature for applications integration.

In a typical scenario where information needs to be shared, data is extracted from the source application or data warehouse, transformed into another format, and then loaded into the target location. Extraction, transformation, and loading (together known as ETL, ELT or DI) are the central processes of data integration. Depending on the nature of the integration scenario, data may need to be merged, aggregated, enriched, summarized, or filtered.

The first step of data transformation is data mapping. Data mapping determines the relationship between the data elements of two applications and establishes instructions for how the data from the source application is transformed before it is loaded into the target application. In other words, data mapping produces the critical metadata that is needed before the actual data conversion takes place.


Wiki:

Data transformation
Data migration
Data conversion
Data mapping
ETL