Yes, Luke Han's idea of some auto-gen stuff for Agg Group is what I thinking about. But the auto-gen maybe difficult to define. In v1.3, it can create hierarchy dimensions by users themselves, users are very clear to know how the hierarchy-relations between various columns. Maybe u can auto-gen it first, and allow users to customize it.
2016-05-10 15:01 GMT+08:00 Luke Han <[email protected]>: > I think Mars' concern is right, we shouldn't introduce too complex concept > for users. > > As most of BI/DW experts, they are familiar to create dimension with > different types: normal, hierarchy, derived... > > The "Aggregation Group" is in Advanced setting which should not open to > Users (Modeler) directly. > > We should move back "hierarchy" to previous place and do some auto-gen > stuff for Agg Group. > > Thanks. > > > > > Best Regards! > --------------------- > > Luke Han > > On Mon, May 9, 2016 at 11:15 PM, Mars J <[email protected]> wrote: > >> what's difference between pre-aggregation and post-aggregation ? >> I have no experience in traditional BI and OLAP, not so clear to this >> concept. >> >> 2016-05-10 13:51 GMT+08:00 ShaoFeng Shi <[email protected]>: >> >>> This is easy in my mind; Firstly you need understand the "derived" >>> dimension; "Derived" dimensions can only be from lookup table, they will >>> be derived from the pk/fk column at runtime; only the FK column will be >>> built into cube; So if you use "derived", you don't need, and have no >>> chance to declare them as hierarchy; >>> >>> Whether define them as a "derived" or "normal" + "hierarchy", depends on >>> how you balance the pre-aggregation and post-aggregation. >>> >>> >>> >>> >>> 2016-05-10 11:45 GMT+08:00 Mars J <[email protected]>: >>> >>>> It's very confused if I want to define a hierachy dim, I need to define >>>> it be normal or derived and then add it to aggregation group for hierachy >>>> dims. if this hierachy dims I want to define includes 3 columns, it will be >>>> 3 dims if define it in normal dims or 1 dim if define it in derived dims. >>>> So how to handle it ? >>>> >>>> 2016-05-10 10:53 GMT+08:00 Mars J <[email protected]>: >>>> >>>>> Hi, >>>>> There is something confused me . In kylin 1.3 ,the dimension >>>>> types are hierachy/derived/normal and mantory when create a cube in the >>>>> dimensions step. In kylin 1.5.1 there 2 types including normal and derived >>>>> in the dimensions step, and in the advanced setting , aggregation group >>>>> has >>>>> some aggregating manner of hierachy/mantory/joint. >>>>> >>>>> I test 1.3 including 2 derived dims and 2 hierachy dims(also has >>>>> 3 columns each dims, level1-> level2 -> level3), I said it has 4 dims in >>>>> the traditional BI way, but in kylin ,it's 10 dims. >>>>> In kylin 1.5.1, I can't create hierachy dims directly, but I can >>>>> create it for derived dims or normal dims first, then in the aggregroup , >>>>> make it to hierachy dims. but I don't know how to count it in traditional >>>>> BI way. >>>>> >>>>> We can discuss about the dims, and the different dims definition. >>>>> >>>> >>>> >>> >>> >>> -- >>> Best regards, >>> >>> Shaofeng Shi >>> >>> >> >
