Tail stage

The Tail Stage is a Development/Debug stage. It can have a single input link and a single output link. It is one of a number of stages that InfoSphere® DataStage® provides to help you sample data, see also:

• Head stage, Head stage.
• Sample stage, Sample stage.
• Peek stage, Peek stage.

The Tail Stage selects the last N records from each partition of an input data set and copies the selected records to an output data set. You determine which records are copied by setting properties which allow you to specify:

• The number of records to copy
• The partition from which the records are copied

This stage is helpful in testing and debugging applications with large data sets. For example, the Partition property lets you see data from a single partition to determine if the data is being partitioned as you want it to be. The Skip property lets you access a certain portion of a data set.

The stage editor has three pages:

• Stage Page. This is always present and is used to specify general information about the stage.
• Input Page. This is where you specify the details about the single input set from which you are selecting records.
• Output Page. This is where you specify details about the processed data being output from the stage.