The naming is not a big issue, but your schema proposals seem to be turning IoTDB into something else.
At 2019-08-14 16:55:33, "Jialin Qiao" <[email protected]> wrote: >Hi, > >I think source or datasource is good, and it's better to use, or at least add >the tags and fields, because many TSDBs use these conceptual module. > >Some feasible schema organization ways and "select * from the table" results: > >(1) Each type of datasource is a table, which has a time column, some tag >columns and some field columns. > >Table: sourceType >time tag1, field1, field2 >1, device1, 1, 1 >2, device1, 2, 2 >2, device2, 2, 2 > >(2) Each datasource is a table with some tags. Each table has a time column, >and some field columns. (Tags of one datasource may be not changed, so just >see it as metadata.) > >Table: source1(tag1=device1) >time, field1, field2 >1, 1, 1 >2, 2, 2 > >Table: source2(tag1=device2) >time, field1, field2 >2, 2, 2 > > >Best, >-- >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: "Julian Feinauer" <[email protected]> >> 发送时间: 2019-08-14 16:10:22 (星期三) >> 收件人: "[email protected]" <[email protected]> >> 抄送: >> 主题: Re: An easier way to create time series. >> >> Hi, >> >> let me stick in hier also. >> One of the things which was at first a bit "unfamiliar" for me was this >> device focus. >> It’s a bit to "one-dimensional" in my perspective. >> >> Personally, I quite like how Influx does it that you have a name and can >> attach tags and fields to it. >> And even if we do not do it that way I would prefer to name it a bit >> differently as "series" or "measurement" or "source". >> Device is a bit specific and just sounds odd, from a users perspective. >> >> I think it was good to keep it that way for 0.8.0. >> But for the next release we are open to break things a bit. >> >> What do others think? >> >> Julian >> >> Am 14.08.19, 04:52 schrieb "Tian Jiang" <[email protected]>: >> >> Maybe starting from a sugar, we can add some improvements gradually. >> Currently, I think making timeseries creation easier should be enough. >> Please share if you have some fancy ideas that can go with the introduction >> of "device". >> >> Tian Jiang >> >> >> At 2019-08-14 10:44:14, "Xiangdong Huang" <[email protected]> wrote: >> >Hi, >> > >> >Looks fine for me. >> > >> >One question, is it just a language syntax sugar, or we can as well as >> >improve the schema management? Any idea? >> > >> >Best, >> >----------------------------------- >> >Xiangdong Huang >> >School of Software, Tsinghua University >> > >> > 黄向东 >> >清华大学 软件学院 >> > >> > >> >Tian Jiang <[email protected]> 于2019年8月14日周三 上午10:37写道： >> > >> >> Greetings, >> >> >> >> >> >> In the present version, it is a little trouble some to create a set >> >> timeseries that has the same measurements. On the other hand, >> although we >> >> use the conception "device" in the code, it is not properly >> abstracted. >> >> >> >> Expected usage: >> >> >> >> Using IoTDB in a more relational way: >> >> >> >> CREATE DEVICE TEMPLATE vehicle (speed DOUBLE PLAIN, direction DOUBLE >> >> PLAIN, temperature DOUBLE PLAIN, fuel DOUBLE PLAIN) >> >> >> >> If all datatypes(or encodings) are the same, you can write the equal >> form: >> >> >> >> CREATE DEVICE TEMPLATE vehicle MEASUREMENTS (speed, direction, >> >> temperature, fuel) DATATYPE DOUBLE ENCODING PLAIN >> >> >> >> Then you will be able to create time series in an easier way: >> >> >> >> CREATE DEVICE (vehicle) root.sg1.vehicle1 >> >> >> >> Which equals: >> >> >> >> CREATE TIMESERIES root.sg1.vehicle1.speed WITH >> >> DATATYPE=DOUBLE,ENCODING=PLAIN >> >> >> >> CREATE TIMESERIES root.sg1.vehicle1.direction WITH >> >> DATATYPE=DOUBLE,ENCODING=PLAIN >> >> >> >> CREATE TIMESERIES root.sg1.vehicle1.fuel WITH >> >> DATATYPE=DOUBLE,ENCODING=PLAIN >> >> >> >> CREATE TIMESERIES root.sg1.vehicle1.temperature WITH >> >> DATATYPE=DOUBLE,ENCODING=PLAIN >> >> >> >> I hope this will narrow the gap between using IoTDB and traditional >> >> relation databases. >> >> Jira link: >> >> >> https://issues.apache.org/jira/projects/IOTDB/issues/IOTDB-163?filter=allopenissues >> >> >> >> >> >> Tian Jiang >> >>
