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 <xujiao.myc...@gmail.com>: > 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 <xujiao.myc...@gmail.com>: > >> 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 <shaofeng...@apache.org>: >> >>> 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 <xujiao.myc...@gmail.com>: >>> >>>> 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 <xujiao.myc...@gmail.com>: >>>> >>>>> 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 <shaofeng...@apache.org>: >>>>> >>>>>> Hi Mars, did you restart kylin server after update this property? >>>>>> >>>>>> 2016-05-11 16:34 GMT+08:00 Mars J <xujiao.myc...@gmail.com>: >>>>>> >>>>>>> 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
