need interview question

Sat, 21 Mar 2015 15:43:18 GMT

what is fact ,dim and fact table ,dim table?

Re: need interview question

fred_s — Sat, 21 Mar 2015 21:58:20 GMT

Hi Suman,

A fact table mostly contains numbers or whatever, the stuff you'd like to calculate, your expressions.

For example your invoices with amount etc

Your invoices table will probably contain a customernumber, but not your customerdata like the customername and address.

Your table with customers contains ways to view your expressions. A view is a dimension.

Your customertable (dimension) contains one customer 'x'.

Your Invoicestable (fact) contains zero, one or more invoices for customer 'x'.

When you create a chart with sum(Amount) per Customer,

sum(Amount) is your expression and Customer is your dimension.

Best datastructure is a starscheme: a facttable (centered) with one or more dimensiontables.