Top-down approach: According to Inmon’s methods, the data warehouse has to be built first. The data derived from the third party’s external system is verified and finally combined into a normalized data model. The data stored in the data warehouse leads to further creation of data marts.
Bottom-up method: According to Kimball’s method, one should create the dimensional data marts first. Data obtained from the systems is passed to the staging area and then shaped into a star schema design. This data is at the end, processed and stored with the data marts and each of the marts focus on the individual business process.
Hybrid method: This is an approach obtained from the combination of both the top-down and bottom-up methods. It means the pace of the bottom-up method is combined with the integration from top-down design.