What do you mean by staging area and write its main purpose?
During the extract, transform, and load (ETL) process, a staging area or landing zone is used as an intermediate storage area. It serves as a temporary storage area between data sources and data warehouses. Staging areas are primarily used to extract data quickly from their respective data sources, therefore minimizing the impact of those sources. Using the staging area, data is combined from multiple data sources, transformed, validated, and cleaned after data has been loaded.
