search

shuijian-xu / hive

0 stars 0 forks source link

When is it a data warehouse and when is it a data mart? #75

Open shuijian-xu opened 5 years ago

shuijian-xu commented 5 years ago

Often, it is the commercial interests of the software vendors that carry the greatest influence. The view is held, by some, that the data warehouse is the big, perhaps enterprise-wide, repository and that data marts are much smaller, maybe departmental, extractions from the warehouse that the users get to analyze.

shuijian-xu commented 5 years ago

In a data warehouse that has an OLAP component, it is that OLAP component that the users actually get to use. Sometimes it is the only part of the warehouse that they have direct access to. This means that the bit of the warehouse that the users actually use is dimensional, irrespective of the underlying data model. In a data warehouse that implements a dimensional model, the bit that the users actually use is, obviously, also dimensional. Therefore, everyone appears to agree that the part that the users have access to should be dimensional. So it appears that the only thing that separates the two camps is some part of the data warehouse that the users do not have access to.