I also encountered the "empty cube" issue in an environment yesterday; By checking Hive I found one of the sample table "DEFAULT.KYLIN_CATEGORY_GROUPINGS" has no record. Since the "kylin_sales" cube uses "inner" joins for all tables, causing the cube no data.
After some troubleshoting I identify it is an issue of the "beeline" client (my env configures beeline as hive cli in kylin), when it executes the sample_cube/create_sample_tables.sql, the last line wasn't executed, which caused the csv file wasn't uploaded. By adding a blank line in the end of this sql file, it runs successfully. I will checkin this change in kylin soon. If you faced the same issue, please take a try. 2016-09-09 13:47 GMT+08:00 ShaoFeng Shi <[email protected]>: > Hi Niasari, > > During the query time, Kylin will not touch Hive, all queries will go to > HBase, so you still get results on kylin_cal_dt; If you also want to remove > that also in Kylin, please disable and then drop the cube. > > For the empty cube, it is possible and allowed in Kylin; Thinking that an > user uses incremental build, and for a time period there is no source data, > so empty cube is expected. Of course you can configure Kylin to let it > report error when there is no source record, see: https://issues.apache. > org/jira/browse/KYLIN-1752 > > For the empty cube issue, I guess there is some thing wrong, making no > data be built into cube. If you want to get remote debug or support, please > contact me offline. > > > > 2016-09-07 5:17 GMT+08:00 Niasari, Mehrdad <[email protected]>: > >> The range is up to 2015 and that’s not the problem. >> >> >> >> The only query that doesn’t return zero/empty result is from table >> kylin_cal_dt. When I delete this table from hive, still the result is not >> empty and Kylin doesn’t complain! Where does Kylin bring the data of this >> table even when it’s not on hive? >> >> Also I checked the cube itself on Hbase and it’s empty. Any other >> suggestion? Can it be because of some wrong configuration in connecting >> Kylin to Hive/Hbase? If that’s the case why it can create the cube >> successfully? >> >> >> >> Also I have a question regarding uuid. What is this for? >> >> I’m asking this cause I cannot fully understand that why you have used a >> fixed value in sample cube json files (for example for kylin_sales_cube >> uuid is: “2fbca32a-a33e-4b69-83dd-0bb8b1f8c53b”). How come it doesn’t >> conflict if you run the sample cube multiple times? >> >> >> >> Thanks, >> >> Mehrdad >> >> >> >> *From:* ShaoFeng Shi [mailto:[email protected]] >> *Sent:* 2016, September, 01 9:01 PM >> >> *To:* user >> *Subject:* Re: Empty Cube >> >> >> >> ok; The table "kylin_sales" contains data for 2012 and 2013, so need make >> sure the build range covers these years; please have a check and I guess it >> is some minor mistake; BTW, empty cube will return zero since it doesn't >> have data. >> >> >> >> 2016-09-02 1:34 GMT+08:00 Niasari, Mehrdad <[email protected]>: >> >> Thanks for the reply. >> >> >> >> There is no error in the log. Also I checked the hive tables and they are >> not empty; I can run any query on them using Hue and work well. >> >> >> >> Also the size of cube in the cubes section in 0.00KB! But even with an >> empty cube the result of queries on the tables should not be empty/zero, >> right? >> >> Any other suggestion how to debug it? >> >> >> >> Thanks, >> >> Mehrdad >> >> >> >> *From:* ShaoFeng Shi [mailto:[email protected]] >> *Sent:* 2016, August, 31 9:04 PM >> *To:* user >> *Subject:* Re: Empty Cube >> >> >> >> Hi Mehrdad, >> >> >> >> When you run the query, is there any error reported in the logs/kylin.log? >> >> >> >> If no error, please check whether the source hive table has data, you can >> do this easily in hive, by running HQL "select * from default.kylin_sales >> limit 100"; it is very likely that the "sample.sh" failed to upload the >> file; if it is this case, you may need manually import the data files >> (sample_cube/data) to hive; >> >> >> >> 2016-09-01 4:06 GMT+08:00 Niasari, Mehrdad <[email protected]>: >> >> Hi All, >> >> >> >> When I run the sample cube of Kylin the result is empty, i.e. the cube is >> computed successfully, the status is ready but nothing is in the cube and >> every query gets zero. >> >> Do you have any suggestion what can cause the problem? >> >> How should I debug it? >> >> >> >> Thanks, >> >> Mehrdad >> >> >> >> >> >> _______________________________________________________________________ >> >> If you received this email in error, please advise the sender (by return >> email or otherwise) immediately. You have consented to receive the attached >> electronically at the above-noted email address; please retain a copy of >> this confirmation for future reference. >> >> Si vous recevez ce courriel par erreur, veuillez en aviser l'expéditeur >> immédiatement, par retour de courriel ou par un autre moyen. Vous avez >> accepté de recevoir le(s) document(s) ci-joint(s) par voie électronique à >> l'adresse courriel indiquée ci-dessus; veuillez conserver une copie de >> cette confirmation pour les fins de reference future. >> >> >> >> >> >> -- >> >> Best regards, >> >> >> >> Shaofeng Shi >> >> >> >> _______________________________________________________________________ >> >> If you received this email in error, please advise the sender (by return >> email or otherwise) immediately. You have consented to receive the attached >> electronically at the above-noted email address; please retain a copy of >> this confirmation for future reference. >> >> Si vous recevez ce courriel par erreur, veuillez en aviser l'expéditeur >> immédiatement, par retour de courriel ou par un autre moyen. Vous avez >> accepté de recevoir le(s) document(s) ci-joint(s) par voie électronique à >> l'adresse courriel indiquée ci-dessus; veuillez conserver une copie de >> cette confirmation pour les fins de reference future. >> >> >> >> >> >> -- >> >> Best regards, >> >> >> >> Shaofeng Shi >> >> >> >> _______________________________________________________________________ >> >> If you received this email in error, please advise the sender (by return >> email or otherwise) immediately. You have consented to receive the attached >> electronically at the above-noted email address; please retain a copy of >> this confirmation for future reference. >> >> Si vous recevez ce courriel par erreur, veuillez en aviser l'expéditeur >> immédiatement, par retour de courriel ou par un autre moyen. Vous avez >> accepté de recevoir le(s) document(s) ci-joint(s) par voie électronique à >> l'adresse courriel indiquée ci-dessus; veuillez conserver une copie de >> cette confirmation pour les fins de reference future. >> >> > > > -- > Best regards, > > Shaofeng Shi > > -- Best regards, Shaofeng Shi 史少锋
