As mentioned in my another Blog
Data Transformation is core of any Business Process. IBM InfoSphere DataStage a leading ETL Tool handle data transformation by providing various annotations, rule expressions, filters, Joins, Aggregation, Functions and many other Transformation Components.
- Transformations Rules can be applied to one or more columns to annotate your mapping specification for the developers that prepares the job.
- A rule expression is a relationship between a set of input data values and a set of result values. Rule Expressions created within the tool can also be used to transform the data.
- Switch expressions in source tables control the data flow to specific targets.
- Filter expressions on the source columns restrict the data that is moved into the target tables. You can add expressions to the source columns that filter out specific data, such as where the account balance is below 100,000.
- With the lookup definition, you add a join on a mapping level rather than on an entire mapping specification level
- Define a join business rule in addition to, or instead of, defining a join in order to provide a textual description of joining data from the sources of the specification.
- Aggregate source data in a mapping specification to capture the business requirement for a data flow.
- The functions that are valid in InfoSphere DataStage and QualityStage Designer are also valid in IBM InfoSphere FastTrack. The list of functions in this section are generally used when defining a column derivation in a Transformer stage.