There's one internal page to introduce all metadata, including terms,
links, and samples.

and, why not you draft one blog for this?
;-)

Thanks.


Best Regards!
---------------------

Luke Han

On Mon, Aug 3, 2015 at 8:15 PM, hongbin ma <[email protected]> wrote:

> Terminology page might be a good entry for these two terms, but I think the
> details should belong to another page. Do we have a doc section to
> introduce kylin internals, or something like "optimizing your cubes" ?
>
> On Mon, Aug 3, 2015 at 8:06 PM, Luke Han <[email protected]> wrote:
>
> > Terminology page is right place designed host such terms:
> >
> > http://kylin.incubator.apache.org/docs/gettingstarted/terminology.html
> > <http://kylin.incubator.apache.org/docs/gettingstarted/terminology.html>
> >
> > Thanks.
> >
> >
> > Best Regards!
> > ---------------------
> >
> > Luke Han
> >
> > On Mon, Aug 3, 2015 at 2:58 PM, hongbin ma <[email protected]> wrote:
> >
> > > Hi Maria
> > >
> > > we do not have a formal doc for this now.
> > > I was planning to refine the materials here in this thread, and publish
> > it
> > > as a formal document if the materials here answers your concerns.
> > >
> > > What are you expecting from the "formal doc"?
> > >
> > > On Mon, Aug 3, 2015 at 2:37 PM, Gaspare Maria <
> > > [email protected]> wrote:
> > >
> > > > Hi,
> > > >
> > > > Good explanation.
> > > >
> > > > Could you share the link to the formal doc you *Hierarchies:* ?
> > > >
> > > > A complete example shown this details will also help.
> > > >
> > > > Thanks.
> > > >
> > > > Gaspare Maria
> > > >
> > > > <div>-------- Messaggio originale --------</div><div>Da: hongbin ma <
> > > > [email protected]> </div><div>Data:03/08/2015  05:32  (GMT+01:00)
> > > > </div><div>A: dev <[email protected]>
> </div><div>Oggetto:
> > > > Re: Modeling hierarchies </div><div>
> > > > </div>hi alex,
> > > >
> > > > I'm not quite following this thread? It looks like except jason
> > > > recommending your the slideshare link, no one is replying you. To
> whom
> > > are
> > > > your communicating? (Is someone sending reply to you in person
> instead
> > of
> > > > to the dev list?)
> > > >
> > > > Can you re-summarize your problem again and I might be able to help
> > you.
> > > > I found you're confused by hierarchies and derived columns, here's
> some
> > > > take-aways, I'm recently summarizing them to formal docs:
> > > >
> > > > *Hierarchies:*
> > > >
> > > > Theoretically for N dimensions you'll end up with 2^N dimension
> > > > combinations. However for some group of dimensions there are no need
> to
> > > > create so many combinations. For example, if you have three
> dimensions:
> > > > continent, country, city (In hierarchies, the "bigger" dimension
> comes
> > > > first). You will only need the following three combinations of group
> by
> > > > when you do drill down analysis:
> > > >
> > > > group by continent
> > > > group by continent, country
> > > > group by continent, country, city
> > > >
> > > > In such cases the combination count is reduced from 2^3=8 to 3, which
> > is
> > > a
> > > > great optimization. The same goes for the YEAR,QUATER,MONTH,DATE
> case.
> > > >
> > > > If we Donate the hierarchy dimension as H1,H2,H3, typical scenarios
> > would
> > > > be:
> > > >
> > > > *A. Hierarchies on lookup table*
> > > >
> > > > Fact  Table                            (joins)         Lookup Table
> > > > ===================                         =============
> > > > column1,column2,,,,,, FK                         PK,,H1,H2,H3,,,,
> > > >
> > > > B. Hierarchies on fact table
> > > >
> > > > Fact  Table
> > > > ===========================
> > > > column1,column2,,,H1,H2,H3,,,,,,,
> > > >
> > > > There is a special case for scenario A, where PK on the lookup table
> is
> > > > accidentally being part of the hierarchies. For example we have a
> > > calendar
> > > > lookup table where cal_dt is the primary key:
> > > >
> > > > *A*. Hierarchies on lookup table over its primary key*
> > > >
> > > > Lookup Table(Calendar)
> > > > ==============================================
> > > > cal_dt(PK), week_beg_dt, month_beg_dt, quarter_beg_dt,,,
> > > >
> > > > For cases like A* what you need is another optimization called
> "Derived
> > > > Columns"
> > > >
> > > > *Derived Columns:*
> > > >
> > > > Derived column is used when one or more dimensions (They must be
> > > dimension
> > > > on lookup table, these columns are called "Derived") can be deduced
> > from
> > > > another(Usually it is the corresponding FK, this is called the "host
> > > > column")
> > > >
> > > > For example, suppose we have a lookup table where we join fact table
> > and
> > > it
> > > > with "where DimA = DimX". Notice in Kylin, if you choose FK into a
> > > > dimension, the corresponding PK will be automatically querable,
> without
> > > any
> > > > extra cost. The secret is that since FK and PK are always identical,
> > > Kylin
> > > > can apply filters/groupby on the FK first, and transparently replace
> > them
> > > > to PK.  This indicates that if we want the DimA(FK), DimX(PK), DimB,
> > DimC
> > > > in our cube, we can safely choose DimA,DimB,DimC only.
> > > >
> > > >
> > > > Fact  Table                                     (joins)
> >  Lookup
> > > > Table
> > > > ========================                         =============
> > > > column1,column2,,,,,, DimA(FK)
>  DimX(PK),,DimB,
> > > DimC
> > > >
> > > > Let's say that DimA(the dimension representing FK/PK) has a special
> > > mapping
> > > > to DimB:
> > > >
> > > > dimA    dimB  dimC
> > > > 1           a        ?
> > > > 2           b        ?
> > > > 3           c        ?
> > > > 4           a        ?
> > > >
> > > > in this case, 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.
> > > Derived
> > > > column(DimB) does not participant in cuboids generation:
> > > >
> > > > original combinations:
> > > > ABC,AB,AC,BC,A,B,C
> > > >
> > > > combinations when driving B from A:
> > > > AC,A,C
> > > >
> > > > at Runtime, in case queries like "select count(*) from fact_table
> inner
> > > > join looup1 group by looup1 .dimB", it is expecting cuboid containing
> > > DimB
> > > > to answer the query. However, DimB will appear in NONE of the cuboids
> > due
> > > > to derived optimization. In this case, we modify the execution plan
> to
> > > make
> > > > it group by  DimA(its host column) first, we'll get intermediate
> answer
> > > > like:
> > > >
> > > > DimA  count(*)
> > > > 1          1
> > > > 2          1
> > > > 3          1
> > > > 4          1
> > > >
> > > > Afterwards, Kylin will replace DimA values with DimB values(since
> both
> > of
> > > > their values are in lookup table, Kylin can load the whole lookup
> table
> > > > into memory and build a mapping for them), and the intermediate
> result
> > > > becomes:
> > > >
> > > > DimB  count(*)
> > > > a          1
> > > > b          1
> > > > c          1
> > > > a          1
> > > >
> > > > After this, the runtime SQL engine(calcite) will further aggregate
> the
> > > > intermediate result to:
> > > >
> > > > DimB  count(*)
> > > > a          2
> > > > b          1
> > > > c          1
> > > >
> > > > this step happens at query runtime, this is what it means "at the
> cost
> > of
> > > > extra runtime aggregation"
> > > >
> > > >
> > > >
> > > >
> > > > On Sat, Aug 1, 2015 at 12:54 AM, alex schufo <[email protected]>
> > > wrote:
> > > >
> > > > > Sorry to be a bit annoying with the topic but I tried different
> > cubes /
> > > > > hierarchies and can never join.
> > > > >
> > > > > Without this basically I cannot use Kylin on PROD for my project.
> > > > >
> > > > > The stack trace:
> > > > >
> > > > > http-bio-7070-exec-3]:[2015-07-31
> > > > >
> > > > >
> > > >
> > >
> >
> 09:42:06,337][ERROR][org.apache.kylin.rest.controller.BasicController.handleError(BasicController.java:52)]
> > > > > -
> > > > >
> > > > > org.apache.kylin.rest.exception.InternalErrorException: Can't find
> > any
> > > > > realization. Please confirm with providers. SQL digest: fact table
> > > > > DEFAULT.SAMPLE_DIM,group by [DEFAULT.SAMPLE_DIM.ID],filter on
> > [],with
> > > > > aggregates[].
> > > > >
> > > > > while executing SQL: "select id from sample_dim group by id LIMIT
> > > 50000"
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.apache.kylin.rest.controller.QueryController.doQueryInternal(QueryController.java:223)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.apache.kylin.rest.controller.QueryController.doQuery(QueryController.java:174)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.apache.kylin.rest.controller.QueryController.query(QueryController.java:91)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.apache.kylin.rest.controller.QueryController$$FastClassByCGLIB$$fc039d0b.invoke(<generated>)
> > > > >
> > > > >         at
> > net.sf.cglib.proxy.MethodProxy.invoke(MethodProxy.java:204)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.springframework.aop.framework.Cglib2AopProxy$CglibMethodInvocation.invokeJoinpoint(Cglib2AopProxy.java:689)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:150)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> com.ryantenney.metrics.spring.TimedMethodInterceptor.invoke(TimedMethodInterceptor.java:48)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> com.ryantenney.metrics.spring.TimedMethodInterceptor.invoke(TimedMethodInterceptor.java:34)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> com.ryantenney.metrics.spring.AbstractMetricMethodInterceptor.invoke(AbstractMetricMethodInterceptor.java:59)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.springframework.aop.framework.Cglib2AopProxy$DynamicAdvisedInterceptor.intercept(Cglib2AopProxy.java:622)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.apache.kylin.rest.controller.QueryController$$EnhancerByCGLIB$$5b607924.query(<generated>)
> > > > >
> > > > >         at sun.reflect.GeneratedMethodAccessor117.invoke(Unknown
> > > Source)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
> > > > >
> > > > >         at java.lang.reflect.Method.invoke(Method.java:606)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.springframework.web.method.support.InvocableHandlerMethod.invoke(InvocableHandlerMethod.java:213)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:126)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:96)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:617)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:578)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:80)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:923)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:852)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:882)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:789)
> > > > >
> > > > >         at
> > javax.servlet.http.HttpServlet.service(HttpServlet.java:646)
> > > > >
> > > > >         at
> > javax.servlet.http.HttpServlet.service(HttpServlet.java:727)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
> > > > >
> > > > >         at
> > > > >
> > org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> com.codahale.metrics.servlet.AbstractInstrumentedFilter.doFilter(AbstractInstrumentedFilter.java:97)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:330)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.springframework.security.web.access.intercept.FilterSecurityInterceptor.invoke(FilterSecurityInterceptor.java:118)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.springframework.security.web.access.intercept.FilterSecurityInterceptor.doFilter(FilterSecurityInterceptor.java:84)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.springframework.security.web.access.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:113)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.springframework.security.web.session.SessionManagementFilter.doFilter(SessionManagementFilter.java:103)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)
> > > > >
> > > > >        at
> > > > >
> > > > >
> > > >
> > >
> >
> org.springframework.security.web.authentication.AnonymousAuthenticationFilter.doFilter(AnonymousAuthenticationFilter.java:113)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.springframework.security.web.servletapi.SecurityContextHolderAwareRequestFilter.doFilter(SecurityContextHolderAwareRequestFilter.java:54)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.springframework.security.web.savedrequest.RequestCacheAwareFilter.doFilter(RequestCacheAwareFilter.java:45)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.springframework.security.web.authentication.www.BasicAuthenticationFilter.doFilter(BasicAuthenticationFilter.java:150)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.springframework.security.web.authentication.ui.DefaultLoginPageGeneratingFilter.doFilter(DefaultLoginPageGeneratingFilter.java:91)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.springframework.security.web.authentication.AbstractAuthenticationProcessingFilter.doFilter(AbstractAuthenticationProcessingFilter.java:183)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.springframework.security.web.authentication.logout.LogoutFilter.doFilter(LogoutFilter.java:105)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.springframework.security.web.context.SecurityContextPersistenceFilter.doFilter(SecurityContextPersistenceFilter.java:87)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.springframework.security.web.FilterChainProxy.doFilterInternal(FilterChainProxy.java:192)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.springframework.security.web.FilterChainProxy.doFilter(FilterChainProxy.java:160)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:346)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:259)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.apache.kylin.rest.filter.KylinApiFilter.doFilterInternal(KylinApiFilter.java:64)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
> > > > >
> > > > >         at
> > > > >
> > com.thetransactioncompany.cors.CORSFilter.doFilter(CORSFilter.java:195)
> > > > >
> > > > >         at
> > > > >
> > com.thetransactioncompany.cors.CORSFilter.doFilter(CORSFilter.java:266)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:220)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:122)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:504)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:170)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
> > > > >
> > > > >         at
> > > > >
> > >
> org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:950)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116)
> > > > >
> > > > >         at
> > > > >
> > > >
> > >
> >
> org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:421)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1074)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:611)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:316)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
> > > > >
> > > > >         at
> > > > >
> > > > >
> > > >
> > >
> >
> org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
> > > > >
> > > > >         at java.lang.Thread.run(Thread.java:744)
> > > > >
> > > > >
> > > > > The result for "select * from sample_dim"
> > > > >
> > > > > ID,DIM1,DIM2
> > > > >
> > > > > 33814,NYC,USA
> > > > >
> > > > > 201431,PARIS,FRANCE
> > > > >
> > > > > etc.
> > > > >
> > > > >
> > > > >
> > > > > On Wed, Jul 29, 2015 at 3:37 PM, alex schufo <[email protected]
> >
> > > > wrote:
> > > > >
> > > > > > So with 0.7.2 the cube builds, and I can see some improvement:
> > > > > >
> > > > > > "select * from SAMPLE_DIM" now returns all the fields, i.e:
> > > > > >
> > > > > > dim1, dim2, dim3, etc., SAMPLE_ID
> > > > > >
> > > > > > and I can see all the values for each field.
> > > > > >
> > > > > > However the join between the fact table and the lookup table
> still
> > > does
> > > > > > not work, it returns:
> > > > > >
> > > > > >     Can't find any realization.
> > > > > >
> > > > > > And if I do "select SAMPLE_ID from SAMPLE_DIM group by SAMPLE_ID"
> > it
> > > > also
> > > > > > returns:
> > > > > >
> > > > > >     Can't find any realization.
> > > > > >
> > > > > > If I do "select SAMPLE_ID from FACT_TABLE group by SAMPLE_ID"
> then
> > I
> > > > get
> > > > > > the list of all SAMPLE_ID as expected.
> > > > > >
> > > > > > If I do "select dim1 from SAMPLE_DIM group by dim1" I also get
> the
> > > list
> > > > > of
> > > > > > all dim1 as expected.
> > > > > >
> > > > > > The same exact query works perfectly on Hive (although it takes a
> > > long
> > > > > > time to be processed of course).
> > > > > >
> > > > > > Am I doing something wrong?
> > > > > >
> > > > > > On Wed, Jul 29, 2015 at 1:35 PM, alex schufo <
> [email protected]
> > >
> > > > > wrote:
> > > > > >
> > > > > >> Ok I guess this is
> > https://issues.apache.org/jira/browse/KYLIN-831,
> > > > > >> right?
> > > > > >>
> > > > > >> I upgraded today to 0.7.2 and hope it solves the problem then.
> > > > > >>
> > > > > >> Regards
> > > > > >>
> > > > > >> On Tue, Jul 28, 2015 at 5:52 PM, alex schufo <
> > [email protected]>
> > > > > >> wrote:
> > > > > >>
> > > > > >>> I still don't understand this.
> > > > > >>>
> > > > > >>> I have a simple fact table and a simple SAMPLE_DIM lookup
> table.
> > > They
> > > > > >>> are joined on SAMPLE_ID.
> > > > > >>>
> > > > > >>> If I do like you say and include all the columns of SAMPLE_DIM
> > as a
> > > > > >>> hierarchy and do not include the SAMPLE_ID then the cube builds
> > > > > >>> successfully but I cannot query with the hierarchy. Any join
> > > results
> > > > in
> > > > > >>> this error:
> > > > > >>>
> > > > > >>> Column 'SAMPLE_ID' not found in table 'SAMPLE_DIM'
> > > > > >>>
> > > > > >>> Indeed if I do a select * from 'SAMPLE_DIM' I can see all the
> > > > hierarchy
> > > > > >>> but not the SAMPLE_ID used to join with the fact table.
> > > > > >>>
> > > > > >>> If I include the SAMPLE_ID in the hierarchy definition then the
> > > cube
> > > > > >>> build fails on step 3 with:
> > > > > >>>
> > > > > >>> java.lang.NullPointerException: Column
> > DEFAULT.FACT_TABLE.SAMPLE_ID
> > > > > does
> > > > > >>> not exist in row key desc
> > > > > >>> at
> > > > >
> > org.apache.kylin.cube.model.RowKeyDesc.getColDesc(RowKeyDesc.java:158)
> > > > > >>> at
> > > > > >>>
> > > > >
> > >
> org.apache.kylin.cube.model.RowKeyDesc.getDictionary(RowKeyDesc.java:152)
> > > > > >>> at
> > > > > >>>
> > > > >
> > > >
> > >
> >
> org.apache.kylin.cube.model.RowKeyDesc.isUseDictionary(RowKeyDesc.java:163)
> > > > > >>> at
> > > > > >>>
> > > > >
> > > >
> > >
> >
> org.apache.kylin.cube.cli.DictionaryGeneratorCLI.processSegment(DictionaryGeneratorCLI.java:51)
> > > > > >>> at
> > > > > >>>
> > > > >
> > > >
> > >
> >
> org.apache.kylin.cube.cli.DictionaryGeneratorCLI.processSegment(DictionaryGeneratorCLI.java:42)
> > > > > >>> at
> > > > > >>>
> > > > >
> > > >
> > >
> >
> org.apache.kylin.job.hadoop.dict.CreateDictionaryJob.run(CreateDictionaryJob.java:53)
> > > > > >>> at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:70)
> > > > > >>> at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:84)
> > > > > >>> at
> > > > > >>>
> > > > >
> > > >
> > >
> >
> org.apache.kylin.job.common.HadoopShellExecutable.doWork(HadoopShellExecutable.java:63)
> > > > > >>> at
> > > > > >>>
> > > > >
> > > >
> > >
> >
> org.apache.kylin.job.execution.AbstractExecutable.execute(AbstractExecutable.java:107)
> > > > > >>> at
> > > > > >>>
> > > > >
> > > >
> > >
> >
> org.apache.kylin.job.execution.DefaultChainedExecutable.doWork(DefaultChainedExecutable.java:50)
> > > > > >>> at
> > > > > >>>
> > > > >
> > > >
> > >
> >
> org.apache.kylin.job.execution.AbstractExecutable.execute(AbstractExecutable.java:107)
> > > > > >>> at
> > > > > >>>
> > > > >
> > > >
> > >
> >
> org.apache.kylin.job.impl.threadpool.DefaultScheduler$JobRunner.run(DefaultScheduler.java:132)
> > > > > >>> at
> > > > > >>>
> > > > >
> > > >
> > >
> >
> java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
> > > > > >>> at
> > > > > >>>
> > > > >
> > > >
> > >
> >
> java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
> > > > > >>> at java.lang.Thread.run(Thread.java:744)
> > > > > >>>
> > > > > >>> (the SAMPLE_ID *does* exist in the FACT_TABLE)
> > > > > >>>
> > > > > >>> The only scenario I could make it work is when I also create a
> > > > derived
> > > > > >>> dimension SAMPLE_ID / something else, then somehow the
> SAMPLE_ID
> > is
> > > > > >>> included and can be queried.
> > > > > >>>
> > > > > >>> Any help with that?
> > > > > >>>
> > > > > >>>
> > > > > >>> On Fri, Jun 19, 2015 at 1:37 PM, alex schufo <
> > [email protected]
> > > >
> > > > > >>> wrote:
> > > > > >>>
> > > > > >>>> Thanks for the answer,
> > > > > >>>>
> > > > > >>>> Indeed I had a look at these slides before and it's great to
> > > > > understand
> > > > > >>>> the high level concepts but I ended up spending quite some
> time
> > > when
> > > > > >>>> designing my dimensions with the issues mentioned below.
> > > > > >>>>
> > > > > >>>> On Fri, Jun 19, 2015 at 11:23 AM, jason zhong <
> > > > [email protected]
> > > > > >
> > > > > >>>> wrote:
> > > > > >>>>
> > > > > >>>>> Hi Alex,
> > > > > >>>>>
> > > > > >>>>> We have a slide to hlep you understand how to build cube.I
> > don't
> > > > know
> > > > > >>>>> whether you have read this? This will hlep you understand
> > derived
> > > > and
> > > > > >>>>> hierarchy.
> > > > > >>>>>
> > > > > >>>>>
> http://www.slideshare.net/YangLi43/design-cube-in-apache-kylin
> > > > > >>>>>
> > > > > >>>>> for your case about hierarchy,log_date should not be included
> > in
> > > > > >>>>> hierarchy
> > > > > >>>>> ,here's a bug you help find it.we will follow this.
> > > > > >>>>>
> > > > > >>>>> also .more document and UI enhancement will be done to help
> > user
> > > > > build
> > > > > >>>>> cube
> > > > > >>>>> easily.
> > > > > >>>>>
> > > > > >>>>> Thanks!!
> > > > > >>>>>
> > > > > >>>>> On Fri, Jun 12, 2015 at 5:07 PM, alex schufo <
> > > [email protected]
> > > > >
> > > > > >>>>> wrote:
> > > > > >>>>>
> > > > > >>>>> > I am trying to create a simple cube with a fact table and 3
> > > > > >>>>> dimensions.
> > > > > >>>>> >
> > > > > >>>>> > I have read the different slideshares and wiki pages, but I
> > > found
> > > > > >>>>> that the
> > > > > >>>>> > documentation is not very specific on how to manage
> > > hierarchies.
> > > > > >>>>> >
> > > > > >>>>> > Let's take this simple example :
> > > > > >>>>> >
> > > > > >>>>> > Fact table: productID, storeID, logDate, numbOfSell, etc.
> > > > > >>>>> >
> > > > > >>>>> > Date lookup table : logDate, week, month, quarter, etc.
> > > > > >>>>> >
> > > > > >>>>> > I specified Left join on logDate, actually when I specify
> > this
> > > I
> > > > > >>>>> find it
> > > > > >>>>> > not very clear which one is considered to be the Left table
> > and
> > > > > >>>>> which one
> > > > > >>>>> > is considered to be the Right table. I assumed the Fact
> table
> > > was
> > > > > >>>>> the left
> > > > > >>>>> > table and the Lookup table the right table, looking at it
> > now I
> > > > > >>>>> think that
> > > > > >>>>> > might be a mistake (I am just interested in dates for which
> > > there
> > > > > are
> > > > > >>>>> > results in the fact table).
> > > > > >>>>> >
> > > > > >>>>> > If I use the auto generator it creates a derived
> dimension, I
> > > > don't
> > > > > >>>>> think
> > > > > >>>>> > that's what I need.
> > > > > >>>>> >
> > > > > >>>>> > So I created a hierarchy, but again to me it's clearly
> > > indicated
> > > > > if I
> > > > > >>>>> > should create ["quarter", "month", "week", "log_date"] or
> > > > > ["logDate",
> > > > > >>>>> > "week", "month", "quarter"]?
> > > > > >>>>> >
> > > > > >>>>> > Also should I include log_date in the hierarchy? To me it
> was
> > > > more
> > > > > >>>>> > intuitive not to include it because it's already the join,
> > but
> > > it
> > > > > >>>>> created
> > > > > >>>>> > the cube without it and I cannot query by date, it says
> that
> > > > > >>>>> "log_date" is
> > > > > >>>>> > not found in the date table (it is in the Hive table but
> not
> > > the
> > > > > cube
> > > > > >>>>> > built). If I include it in the hierarchy the cube build
> fails
> > > > with
> > > > > >>>>> this
> > > > > >>>>> > error :
> > > > > >>>>> >
> > > > > >>>>> > java.lang.NullPointerException: Column
> > > > DEFAULT.DATE_TABLE.LOG_DATE
> > > > > >>>>> > does not exist in row key desc
> > > > > >>>>> >         at
> > > > > >>>>> >
> > > > > >>>>>
> > > > >
> > org.apache.kylin.cube.model.RowKeyDesc.getColDesc(RowKeyDesc.java:158)
> > > > > >>>>> >         at
> > > > > >>>>> >
> > > > > >>>>>
> > > > >
> > >
> org.apache.kylin.cube.model.RowKeyDesc.getDictionary(RowKeyDesc.java:152)
> > > > > >>>>> >         at
> > > > > >>>>> >
> > > > > >>>>>
> > > > >
> > > >
> > >
> >
> org.apache.kylin.cube.model.RowKeyDesc.isUseDictionary(RowKeyDesc.java:163)
> > > > > >>>>> >         at
> > > > > >>>>> >
> > > > > >>>>>
> > > > >
> > > >
> > >
> >
> org.apache.kylin.cube.cli.DictionaryGeneratorCLI.processSegment(DictionaryGeneratorCLI.java:51)
> > > > > >>>>> >         at
> > > > > >>>>> >
> > > > > >>>>>
> > > > >
> > > >
> > >
> >
> org.apache.kylin.cube.cli.DictionaryGeneratorCLI.processSegment(DictionaryGeneratorCLI.java:42)
> > > > > >>>>> >         at
> > > > > >>>>> >
> > > > > >>>>>
> > > > >
> > > >
> > >
> >
> org.apache.kylin.job.hadoop.dict.CreateDictionaryJob.run(CreateDictionaryJob.java:53)
> > > > > >>>>> >         at
> > > > > org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:70)
> > > > > >>>>> >         at
> > > > > org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:84)
> > > > > >>>>> >         at
> > > > > >>>>> >
> > > > > >>>>>
> > > > >
> > > >
> > >
> >
> org.apache.kylin.job.common.HadoopShellExecutable.doWork(HadoopShellExecutable.java:63)
> > > > > >>>>> >         at
> > > > > >>>>> >
> > > > > >>>>>
> > > > >
> > > >
> > >
> >
> org.apache.kylin.job.execution.AbstractExecutable.execute(AbstractExecutable.java:107)
> > > > > >>>>> >         at
> > > > > >>>>> >
> > > > > >>>>>
> > > > >
> > > >
> > >
> >
> org.apache.kylin.job.execution.DefaultChainedExecutable.doWork(DefaultChainedExecutable.java:50)
> > > > > >>>>> >         at
> > > > > >>>>> >
> > > > > >>>>>
> > > > >
> > > >
> > >
> >
> org.apache.kylin.job.execution.AbstractExecutable.execute(AbstractExecutable.java:107)
> > > > > >>>>> >         at
> > > > > >>>>> >
> > > > > >>>>>
> > > > >
> > > >
> > >
> >
> org.apache.kylin.job.impl.threadpool.DefaultScheduler$JobRunner.run(DefaultScheduler.java:132)
> > > > > >>>>> >         at
> > > > > >>>>> >
> > > > > >>>>>
> > > > >
> > > >
> > >
> >
> java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
> > > > > >>>>> >         at
> > > > > >>>>> >
> > > > > >>>>>
> > > > >
> > > >
> > >
> >
> java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
> > > > > >>>>> >         at java.lang.Thread.run(Thread.java:744)
> > > > > >>>>> >
> > > > > >>>>> > result code:2
> > > > > >>>>> >
> > > > > >>>>> >
> > > > > >>>>> > I think it might be useful to improve the documentation to
> > > > explain
> > > > > >>>>> this
> > > > > >>>>> > more clearly and not just the basic steps because building
> a
> > > cube
> > > > > >>>>> even on
> > > > > >>>>> > short time ranges takes some time so learning by trial /
> > error
> > > is
> > > > > >>>>> very time
> > > > > >>>>> > consuming.
> > > > > >>>>> >
> > > > > >>>>> > Same thing for the derived dimensions, should I include
> > > > ["storeID",
> > > > > >>>>> > "storeName"] or just ["storeName"]? The second option seems
> > to
> > > > work
> > > > > >>>>> for me.
> > > > > >>>>> >
> > > > > >>>>> > Thanks
> > > > > >>>>> >
> > > > > >>>>>
> > > > > >>>>
> > > > > >>>>
> > > > > >>>
> > > > > >>
> > > > > >
> > > > >
> > > >
> > > >
> > > >
> > > > --
> > > > Regards,
> > > >
> > > > *Bin Mahone | 马洪宾*
> > > > Apache Kylin: http://kylin.io
> > > > Github: https://github.com/binmahone
> > > >
> > >
> > >
> > >
> > > --
> > > Regards,
> > >
> > > *Bin Mahone | 马洪宾*
> > > Apache Kylin: http://kylin.io
> > > Github: https://github.com/binmahone
> > >
> >
>
>
>
> --
> Regards,
>
> *Bin Mahone | 马洪宾*
> Apache Kylin: http://kylin.io
> Github: https://github.com/binmahone
>

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