Staging

Staging serves as a gateway for integrating data from multiple schemas, and delivering the same to the data mart. Staging is required for an ETL process to deliver functionally correct data with the least impact on the source system. The advantages of the staging process are as follows:

Staging reduces the load on the production server by ensuring that the incremental data is first copied to a staging. Then, the transforms are applied from the staging to the data mart.
In a sharded mode, staging helps obtain data from multiple colonies into a single data mart.

Note: Business Intelligence does not provide a staging database, however, if you have deployed a sharded environment, it is recommended that you create a staging database to consolidate the data.