When mapping the Read operation in an entity set, you can map input, output, and changing parameters of the properties.
Also, you can include constant values in the mapping.
In addition, you can use the Propose Mapping button to automatically generate and display the available mapping relations between the properties of the entity set and the parameters of the data source.
If there is no information about the mapping, no mapping is proposed.
To map the Read operation, see Creating the Mapping.
Mapping Rules for Read Operation
The following are some of the mapping rules for read operations:
When mapping a property that is not set as key, it must be of type, output.
You must map at least one data source parameter as type, output.
All properties that are set as key must be mapped as input, or output.
If you provide constant values, they must be of type, input.