An operational data store (ODS) is a type of database often 
used as an interim area for a data warehouse. Unlike a data 
warehouse which contains static data the contents of the 
ODS are updated through the course of business operations. 
An ODS is designed to quickly perform relatively simple 
queries on small amounts of data (such as finding the 
status of a customer order) rather than the complex 
queries on large amounts of data typical of the data 
warehouse. An ODS is similar to your short term memory in 
that it stores only very recent information; in comparison 
the data warehouse is more like long term memory in that it 
stores relatively permanent information.

But in staging we are storing current as well as historic 
data. This data might be a raw and then need cleansing and 
transform before load into datawarehouse.

Data Staging is also called 'Operational Data Store'(ODS). It is a data holding place where the data which is extracted from all the data sources are stored. From the staging area the data is loaded to DWH. Data cleansing takes place in this stage.

ODS Operational Data Store is majorly different from Staging in the below
aspects:

- Existing Records in the System can get updated based on necessary instructions
& design.

- It can be used for immediate reporting if the DW is not in place.

What is Common?

- Transformation/Data check/Validation/Applying Filters/Rules can be done in
both these systems.

- They both are/can be used as a data feed for DW Loading.