What are the various approaches of building a Data warehouse?
This is a generic question: From a business perspective, it is very important to first get clarity on the end user requirements and a system study before commencing any Data warehousing project. From a technical perspective, it is important to first understand the dimensions and measures, determine quality and structure of source data from the OLTP systems and then decide which dimensional model to apply, i.e. whether we do a star or snowflake or a combination of both. From a conceptual perspective, we can either go the Ralph Kimball method (build data marts and then consolidate at the end to form an enterprise Data warehouse) or the Bill Inmon method (build a large Data warehouse and derive data marts from the same. In order to decide on the method, a strong understanding of the business requirement and data structure is needed as also consensus with the customer.
