The following block diagram illustrates the SAP DB components that are involved when you load and unload data, and shows how they work together with an external backup tool.
By using the SAP DB Loader client, you enter the command for loading data and in doing so you call the program loader server. The loader server then creates the pipes. At the same time, the server calls the external backup tool and tells it from which external backup tool to load the data. The client of the external backup tool requests the specified backup medium from the backup server. The server gets the medium, reads the data to be loaded from the backup medium, and transfers the data to the client of the external backup medium. The client writes the data sequentially into the pipes. There the loader server reads them and loads them into the database instance.
By using the SAP DB Loader client, you enter the command for unloading data and in doing so you call the program loader server. The loader server then creates the pipes. The server starts to unload the data and write it sequentially into the pipes. At the same time, the server calls the external backup tool. The backup tool reads the data sequentially from the pipes and saves it on a permanent medium.