A transformation generates repeatable data when it generates rows in the same order between session runs. Transformations produce repeatable data based on the transformation type, the transformation configuration, or the mapping configuration.
Transformations produce repeatable data in the following circumstances:
The order of the output data is consistent between session runs even if the order of the input data is inconsistent between session runs.
Based on input order.
The transformation produces repeatable data between session runs when the order of the input data from all input groups is consistent between session runs. If the input data from any input group is not ordered, then the output is not ordered.
When a transformation generates repeatable data based on input order, during session validation, the Workflow Manager validates the mapping to determine if the transformation can produce repeatable data. For example, an Expression transformation produces repeatable data only if it receives repeatable data.
The order of the output data is inconsistent between session runs.