Kylin caches recent query results. If the same query come in again and hits cache, the the previous result is returned immediately. This may explain why your second request of the same query is super fast.
On Fri, Aug 19, 2016 at 11:10 AM, Mars J <[email protected]> wrote: > just 'select A,B from Fact f left join dima a on f.no=a.no...', when I > query this, it needs 10+s, then the same sql will return result in 0.0s, > but when I change the limit N or any column behind 'select' and 'group by' > and join table ,it costs more than 10+s again. > the source records in fact and dima is 160w , and count no in htable is > 1.9billion. > > 2016-08-18 17:50 GMT+08:00 Li Yang <[email protected]>: > > > Performance troubleshoot is complicated and requires much information. If > > you can share a diagnosis pack, people maybe able to help. > > > > On Sat, Aug 13, 2016 at 10:32 PM, Yiming Liu <[email protected]> > > wrote: > > > > > What's kind of queries? How many records supposed to be returned? Could > > you > > > send out the query log together? > > > > > > 2016-08-12 10:28 GMT+08:00 Mars J <[email protected]>: > > > > > > > Hi, > > > > I have run Kylin 1.5.2.1 and build a cube successfully,the cube > > size > > > is > > > > 3.2G for fact table and dimensional table have 1.5 million records > > > > seperately.HTable count is about 200 billion. > > > > My Cube Design includes 3 Derived Dims and 5 Normal Dims which > > formed > > > a > > > > hierachy dim in agg. Rowkeys are generated automatically,the first > and > > > > second rowkey is the highest cardinality column in fact table and one > > dim > > > > table seperately. > > > > > > > > When I query it from kylin insight, it costs 11s,and the second > > same > > > > query is also 10+s, How can I optimize this ? > > > > > > > > > > > > > > > > -- > > > With Warm regards > > > > > > Yiming Liu (刘一鸣) > > > > > >
