"joint" just tell Kylin to prune certain combinations; for example, "joint AB" will prune all combinations that only has A or only has B; the order in "joint" doesn't matter;
for case 3), it should not be allowed on Kylin's GUI, can you verify? 2016-07-01 14:47 GMT+08:00 Richard Calaba (Fishbowl) <[email protected]>: > Ok, so AB are joined, if: > > > > 1) *Both* A and B have to be specified in either in WHERE-clause or > GROUP BY-clause ; or one in WHERE and the other in GROUP-BY > > > > 2) The order of the Joint Dimension is or is NOT important ??? If AB > is joint, then BA is also joint, right? > > > > Meaning "select ... group by B, A" or "select ... where B = xx group by > A" is also valid for AB as joint-dimension ??? > > > > 3) If AB is joint and AC is joint: > > a. It does NOT mean that ABC is necessarily joint group, right ??? > > b. Also BC doesn’t have to be joint, correct ?? > > > > Thanx, Richard. > > > > *From:* ShaoFeng Shi [mailto:[email protected]] > *Sent:* Thursday, June 30, 2016 7:45 PM > *To:* [email protected] > *Subject:* Re: Joint VS Derived > > > > This slide has introduction on the Derived Dim: > http://www.slideshare.net/YangLi43/design-cube-in-apache-kylin > > > > "Joint" is introduced since 1.5.1; Using "joint" to combine multiple > dimensions into "one" ; Say if you have Dim A, B, C; among them AB are > always appeared together, e.g, "select ... group by A, B" or "select ... > where A = xx group by B"; in this case you can declare AB as "joint"; for > Kylin it looks like a 2 dim cube: AB, C, the combinations are decreased > from 2^3 to 2^2; > > > > 2016-06-30 6:56 GMT+08:00 Alberto Ramón <[email protected]>: > > Hi > > I don't understand the difference between: > > - Joint Dim (from Dimension Step ) > - Derived Dim (from Advance Setings Step) > > Some example ? :) > > > > > > -- > > Best regards, > > > > Shaofeng Shi > > > > No virus found in this message. > Checked by AVG - www.avg.com > Version: 2016.0.7640 / Virus Database: 4613/12530 - Release Date: 07/01/16 > -- Best regards, Shaofeng Shi
