Source data is often structured and formatted to satisfy the requirements of operational application programs, and is not well suited for end users of data warehouses. Data must often undergo considerable transformation before it becomes part of the data warehouse. DB2 Universal Database and the DB2 Warehouse Manager include over 100 built-in transformers that you can use to cleanse, restructure, correlate, standardize, and summarize data to make it more accurate and usable. There are four types of transformers: SQL functions, warehouse transformers, statistical transformers, and user-defined functions.

The SQL functions assist you in performing various field-level and table-level transformations. The field-level transformations include string manipulation, data type conversion, arithmetic calculations, and Boolean operations. Table-level transformations include average, median, minimum, maximum, rollup along a dimension, cube calculations, and more.