Hi Mars please don't increase kylin.cube.aggrgroup.max.combination to a huge number to address the issue. kylin.cube.aggrgroup.max.combination is to prevent a cube from having too many combinations(cuboids), which might lead to a hard time for cube building. You're suggested to take a look at how "joint dimensions" can help here ( http://kylin.apache.org/blog/2016/02/18/new-aggregation-group/)
On Thu, May 12, 2016 at 8:20 PM, Mars J <[email protected]> wrote: > Thanks so much~ > > 2016-05-12 16:00 GMT+08:00 ShaoFeng Shi <[email protected]>: > >> One combination represents one cuboid; A N-dimension full cube has 2^N >> combinations/cuboids; >> The dimension types have the same semantic in old and new algorithms. >> >> 2016-05-12 11:14 GMT+08:00 Mars J <[email protected]>: >> >>> Sorry , there is another problem, is the new cube algorithm for various >>> dimensions type different from the old one ? >>> >>> 2016-05-12 8:47 GMT+08:00 Mars J <[email protected]>: >>> >>>> what's the combination's meaning ? what's the relation between number >>>> of combination and number of dimensions ? >>>> >>>> 2016-05-11 22:35 GMT+08:00 ShaoFeng Shi <[email protected]>: >>>> >>>>> change "kylin.cube.aggrgroup.max.combination" to 8092 isn't enough >>>>> for your case, because you're trying to put 18 dimensions into one >>>>> aggregation group, with 4 hierarchyes (each has 3 dim); You can calculate >>>>> the combination numbers beyond of 8092; You can see some detail info >>>>> in the log. >>>>> >>>>> Kylin makes this check is telling user not to put too many dimensions >>>>> into one agg group; if you do need do so, try your best to leverage the >>>>> optimizations to reduce the combinations; Otherwise, the cube may explode >>>>> too much. >>>>> >>>>> My suggestion is trying to divide your dimensions into multiple groups >>>>> based on the query patterns. >>>>> >>>>> 2016-05-11 19:22 GMT+08:00 Mars J <[email protected]>: >>>>> >>>>>> Hi ShaoFeng, >>>>>> >>>>>> My former manipulation is to set : >>>>>> kylin.cube.aggrgroup.max.size=24 >>>>>> kylin.cube.aggrgroup.max.combination=8092 >>>>>> and restart kylin server,but it didn't work. >>>>>> >>>>>> I update the properties to values as follow just now: >>>>>> kylin.cube.aggrgroup.max.size=48 >>>>>> kylin.cube.aggrgroup.max.combination=16384 >>>>>> >>>>>> and then restart kylin server, it can crerate cube successfully. >>>>>> >>>>>> Now, I don't know what is the appropriate value to set it and this >>>>>> two properties stand for what ? >>>>>> >>>>>> 2016-05-11 19:15 GMT+08:00 Mars J <[email protected]>: >>>>>> >>>>>>> Yes, I have restart kylin server after update this property. but the >>>>>>> error is still there. >>>>>>> >>>>>>> 2016-05-11 17:20 GMT+08:00 ShaoFeng Shi <[email protected]>: >>>>>>> >>>>>>>> Hi Mars, did you restart kylin server after update this property? >>>>>>>> >>>>>>>> 2016-05-11 16:34 GMT+08:00 Mars J <[email protected]>: >>>>>>>> >>>>>>>>> Hi, >>>>>>>>> I'm creating a cube, at the "Advanced Setting" step, I have 18 >>>>>>>>> columns in the Agg Group includes like the picture below: >>>>>>>>> [image: 内嵌图片 2] >>>>>>>>> >>>>>>>>> when save this cube , it shows the error message as follow: >>>>>>>>> >>>>>>>>> [image: 内嵌图片 1] >>>>>>>>> >>>>>>>>> then I go to edit kylin.properties to alter the value of >>>>>>>>> kylin.cube.aggrgroup.max.combination, but I didn't find the default >>>>>>>>> value >>>>>>>>> of this property. I think this property is meaning of the number of >>>>>>>>> include >>>>>>>>> number in agg group. I found the default value from github is 4096, >>>>>>>>> and I >>>>>>>>> set it to 8092, also has this error. >>>>>>>>> >>>>>>>>> Please tell me what the right meaning of >>>>>>>>> kylin.cube.aggrgroup.max.combination and how to set it can avoid my >>>>>>>>> error. >>>>>>>>> >>>>>>>>> Thanks. >>>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> -- >>>>>>>> Best regards, >>>>>>>> >>>>>>>> Shaofeng Shi >>>>>>>> >>>>>>>> >>>>>>> >>>>>> >>>>> >>>>> >>>>> -- >>>>> Best regards, >>>>> >>>>> Shaofeng Shi >>>>> >>>>> >>>> >>> >> >> >> -- >> Best regards, >> >> Shaofeng Shi >> >> > -- Regards, *Bin Mahone | 马洪宾* Apache Kylin: http://kylin.io Github: https://github.com/binmahone
