if the dimension's not explicitly specifying, FK is the column that's derived from.
On Thu, Jan 7, 2016 at 11:15 AM, Zhang, Zhong <zzh...@cardlytics.com> wrote: > Hi All, > > I'm confused by the derived dimension. The following > two sentences are the source that I found online to guide > me use derived dimension. It's kind of unclear to me. > > Dimensions on lookup table that can be derived by PK. > -like User ID derives [Name, Age, Gender] > from [1] at page 10 > > Given a value in DimA, the value of DimB is determined, so we say > dimB can be derived from DimA. When we build a cube that contains > both DimA and DimB, we simple include DimA, and marking DimB > as Derived. > from [2] > > Let us use the sample cube "kylin_sales_cube" as the example to > discuss it. There are two derived dimensions: CAL_DT and CATEGORY. > In CAL_DT, which column derives WEEK_BEG_DT? > In CATEGORY, which column derives > "USER_DEFINED_FIELD1","USER_DEFINED_FIELD3","UPD_DATE","UPD_USER"? > > Is derived dimension used only in lookup table? > > [1] > http://www.slideshare.net/YangLi43/design-cube-in-apache-kylin?next_slideshow=5 > [2] > https://mail-archives.apache.org/mod_mbox/incubator-kylin-dev/201507.mbox/%3c82073af5-ae07-4441-bfdf-e8b9d36ff...@163.com%3E > > Best regards, > Zhong > -- Regards, *Bin Mahone | 马洪宾* Apache Kylin: http://kylin.io Github: https://github.com/binmahone
