Hi Narendra,
1. Initial load is to load all data of a certain object.
This is done by tcode R3AS.
You can check the status of the initial load in R3AM1.
For example: you can do initial download for customer_main to load all customers from R/3 to CRM.
2. Upload: upload is to load data from CRM to R/3.
Download: download is to load from R/3 to CRM.
3. Delta load:
Delta load means the data load will be triggered automatically after create/change/delete ect.
For example, if you save a customer in R/3, the change will be automatically sent to CRM.
This is delta download.
Delta load for a certain object is activated after initial load is performed.
You can see the delta event function modules in ERP table TBE31 or CRM tcode R3AC4.
4. Request load:
Request load means that you can load data in tcode R3AR4 via a pre-defined request in tcode R3AR2. In this request you can define what data you want to load by restricting the object and filters in the relevant table fields.
For example, if we want to load a single customer 300896, can define a request in R3AR2 for object CUSTOMER_MAIN and define filters:
Then you start the request load in R3AR4.
The status can be monitored in R3AR3.
Hope this helps.
Best Regards,
Ellen Feng