This is another important refactor since making the build/query engines as plugable. Thanks Yang!
On 12/8/15, 5:47 PM, "Li Yang" <[email protected]> wrote: >This is a bump of KYLIN-976 in case you are not yet aware... > >KYLIN-976 is a refactoring of how Kylin works with aggregation and aims to >allow adding custom aggregation types easily. > >Kylin started with basic support of SUM, COUNT, MAX, MIN, AVG (from sum >and >count), and COUNT_DISTINCT (based on hyperloglog). Later TopN is added in >2.x branch. And the list is growing for sure. Xiaoyu is working on storing >raw records as a special type of measure (KYLIN-1122), also Yerui is >working on precise count distinct using bitmap (KYLIN-1186). > >The possibility is unlimited. Implement a domain specific aggregation is >now quite easy. E.g. aggregate user events to detect time serials or >access >patterns. Or draw a sketch of certain user groups. Or pre-calculate >clusters of data points. Or histogram... Use your imagination. > >Whoever interested can peek at MeasureTypeFactory and MeasureType on 2.x >branch. The API may still change, but at the same time is stable enough >for >pilots. The javadoc should get you started. HLLCMeasureType and >TopNMeasureType are two good examples. > > >Cheers >Yang
