You can create a Read transformation from a physical data object or a logical data object. If you want to create a Read transformation from a physical data object that you imported from a PowerExchange® adapter source, the mapping editor might prompt you to specify a read operation before you can create a Read transformation from the data object.

You can configure different properties for a Read transformation based on the type of data object that you used to create the transformation. For example, if you create a Read transformation from a relational data object, you can configure SQL overrides and define constraints. The properties that you can configure also depend on whether you have configured parameters for the transformation.

Read transformations can contain dynamic sources. You can configure a Read transformation to dynamically update its ports, metadata, and other properties. For information about configuring dynamic sources, read the "Dynamic Mappings" chapter in the

Informatica Developer Mapping Guide

.