data warehouse - When we use Datamart and Datawarehousing? -

i new dw . when should use term datamart , when should use term datawarehousing . please explain example may own example or in terms of adventureworks .

i'm don't work on ms sql server. here's generic example business use case.

let me add term this. first off, there main transactional database interacts application (assuming have application interact with, obviously). data gets written master database (hopefully, using master-slave replication), , simultaneously gets copied salve. according business , reporting requirements, cleansing , etl performed on application data , data aggregated , stored in denormalized form improve reporting performance , reduce number of joins. complex pre-calculated data readily available business user reporting , analysis purposes. dimensional database - denormalized form of main transactional database (most in 3nf).

but, may know, businesses have different supporting systems bring in data in form of spreadsheets, csvs , flatfiles. data single domain, such as, call center, collections on , forth. can call every such separate domain data data mart. data different domains operated upon etl tool , denormalized in own fashion. when combine datamarts , dimensional databases solving reporting , analysis problem business, data warehouse.

assume have major application, running on website - main business. have primary consumer interaction on website. give primary dimensional database. consumer support, may have separate solution, such avaya or genesys implemented in company - provide data on same (or different server). prepare etls load data onto own server. call resultant data data marts. , combine of these things data warehouse. know, being repetitive on purpose.