What is difference between Delta Import and Delta Import(Stage Only) ?

There is no difference between them - in Configure Run Profiles you have Delta Import (Stage Only). The other one with Delta Import is Delta Import and Delta Synchronization. Both of them: An import from a data source where only the changes that have occurred since the last import are imported.

Thank you. Delta import(stage only) import to CS ,not to MV ?

That is correct. The import brings into the connector space a representation of the object(s) in the connected data source. The synchronization step applies filters, join and projection rules, and then import attribute flow rules. Nothing happens regarding the metaverse object until a synchronization touches the connector space object. There is an important distinction between a delta import and sync in a single run profile step, and separating them into two steps (delta import, and then delta sync separately). When combined the DIDS only synchronizes the objects that changed in that delta import. A delta synchronization processes all updates that were imported, but also evaluates ALL disconnectors. The disconnectors are processed in case there is a metaverse object the connector space object can join to, since no change in the object may be needed if what was required was a creation of, or change in, a metaverse object based on another management agent's operation. Chris