When you persist and bind mapping outputs, define a filter query for the Read transformation and a mapping output expression in an Expression transformation. The filter query checks new data against the persisted output value. The mapping output expression aggregates an output value for the mapping.

When you define the mapping parameter, assign a default value for the parameter. When you bind a mapping output to a mapping parameter, the persisted output overrides the default value unless you configure a value for the same parameter in a parameter set or parameter file. If you define a parameter value in a parameter set or parameter file, that value will be used for the parameter.

You must set a run-time instance name to persist mapping output values. To set a run-time instance name, use the -RuntimeInstanceName option for the infacmd ms runMapping command. For more information, see the

Informatica Command Reference

.

A use case for binding is to persist the latest ID number that the mapping processes. The next time that the mapping runs, the mapping parameter uses the value of the last ID processed. The mapping can filter the parameter source rows to include only the rows with an order date greater than the last order date processed.