Hi, +1 for "order by latest".
Jialin Qiao <[email protected]> 于2020年6月10日周三 下午8:51写道： > Hi, > > Order by latest is ok. What do you think, Huang? > > Thanks, > -- > Jialin Qiao > School of Software, Tsinghua University > > 乔嘉林 > 清华大学 软件学院 > > > -----原始邮件----- > > 发件人: "田原" <[email protected]> > > 发送时间: 2020-06-10 20:20:06 (星期三) > > 收件人: [email protected] > > 抄送: > > 主题: Re: Re: I've submitted a PR for ISSUE-1281 > > > > Hi, > > > > I also think 'order by latest' is better. > > What do you think, Qiao? > > > > Best, > > --------------- > > Yuan Tian > > > > > > > > > -----原始邮件----- > > > 发件人: "孙泽嵩" <[email protected]> > > > 发送时间: 2020-06-10 18:07:09 (星期三) > > > 收件人: [email protected] > > > 抄送: > > > 主题: Re: I've submitted a PR for ISSUE-1281 > > > > > > Hi Jialin, > > > > > > > I come up a scenario: If a series receives a point of last year now, > is the series hot? > > > Good scenario. > > > > > > How about “order by latest” ? Since “LAST” is related to another > function … > > > > > > Best, > > > ----------------------------------- > > > Zesong Sun > > > School of Software, Tsinghua University > > > > > > 孙泽嵩 > > > 清华大学 软件学院 > > > > > > > 2020年6月10日 16:38，Jialin Qiao <[email protected]> 写道： > > > > > > > > Hi > > > > > > > > To show timeseries and display them by the descending order of the > timestamp of the last point. > > > > > > > > The new grammar is designed as "order by heat". > > > > E.g., the last time of s1 is 10, the last time of s2 is 8. When > order by heat, the result will display as "s1, s2". > > > > > > > > I come up a scenario: If a series receives a point of last year now, > is the series hot? > > > > > > > > Or "order by last" ? > > > > > > > > Thanks, > > > > -- > > > > Jialin Qiao > > > > School of Software, Tsinghua University > > > > > > > > 乔嘉林 > > > > 清华大学 软件学院 > > > > > > > >> -----原始邮件----- > > > >> 发件人: "田原" <[email protected]> > > > >> 发送时间: 2020-06-10 15:41:42 (星期三) > > > >> 收件人: [email protected] > > > >> 抄送: > > > >> 主题: I've submitted a PR for ISSUE-1281 > > > >> > > > >> Hi, > > > >> > > > >> I submitted a pr to add an order-by-heat feature in show time > series syntax. > > > >> > > > >> > > > >> PR: > https://github.com/apache/incubator-iotdb/pull/1341 > > > >> > > > >> ISSUE-1281: > https://github.com/apache/incubator-iotdb/issues/1281 > > > >> > > > >> > > > >> Best, > > > >> --------------- > > > >> Yuan Tian > > > >> > > > >> > > > >>> -----原始邮件----- > > > >>> 发件人: "田原" <[email protected]> > > > >>> 发送时间: 2020-06-10 15:29:16 (星期三) > > > >>> 收件人: [email protected] > > > >>> 抄送: > > > >>> 主题: [ISSUE-1281] Show timeseries in descending ordered of last > point time > > > >>> > > > >>> Hi, > > > >>> > > > >>> > > > >>> I'm working on the issue-1281( > https://github.com/apache/incubator-iotdb/issues/1281). I plan to add a > sub clause in show timeseries syntax, like: > > > >>> > > > >>> > > > >>> SHOW TIMESERIES prefixPath? showWhereClause? orderByHeatClause? > limitClause? > > > >>> > > > >>> > > > >>> The 'orderByHeatClause' is added to support this feature. The > detailed syntax is: > > > >>> > > > >>> > > > >>> orderByHeatClause > > > >>> : ORDER BY HEAT > > > >>> ; > > > >>> > > > >>> > > > >>> It's an optional clause, if user doesn't specify it. The action of > 'show timeseries' will just be like before, the result set is sorted by the > registered time of the time series. > > > >>> > > > >>> > > > >>> If it is specified, firstly we will obtain all the satisfying > timeseries as before, then we will sort them by the last point's timestamp. > That means if the timeseries is inserted recently, it will be shown in the > front. > > > >>> > > > >>> > > > >>> In the implementation, as we have got the LeafMNode before, so we > can use the cachedLastValuePair field in it to get last timestamp, if the > cachedLastValuePair is null, we will construct a LastQueryPlan to get it. > > > >>> > > > >>> > > > >>> Best, > > > >>> --------------- > > > >>> Yuan Tian > > > > -- Best, Xiangwei Wei
