Hi Julian，
He is my friend and contacted me offline, because I advertise IoTDB in my
weChat(like facebook or twitter).
Next time I will try to let him put issue in the mail list himself :)
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: "Jul
Hi,
I try to make this proposal more concrete from a semantic perspective.
Consider the sql "select * from root.sg_1". The following format is the "wide"
table:
The following format is the "narrow" table:
The levels of data from low to high are:
- sensor data, or series data, e.g., from r
Sorry, pictures cannot be attached in the last email I sent. So I supplement
them here in text.
The "wide" table is:
| time | root.sg_1.device_1.sensor_1 | root.sg_1.device_1.sensor_2 |
root.sg_1.device_2.sensor_1 | root.sg_1.device_2.sensor_2 |
| 1 | 100 | 2.5 | 99 | 1.3 |
| ... | ... | ... | ..
Sorry, pictures cannot be attached in the last email I sent. So I supplement
them here in text.
The "wide" table is:
| time | root.sg_1.device_1.sensor_1 | root.sg_1.device_1.sensor_2 |
root.sg_1.device_2.sensor_1 | root.sg_1.device_2.sensor_2 |
| 1 | 100 | 2.5 | 99 | 1.3 |
| ... | ... | ... | ..
Hi,
Glad to see this discussion.
I am on my travel so I have no enough time these days to join with you but
I will never miss this discussion..
The discussion is important because the query is the highest frequent
function that user use IoTDB and make data valuable.
Besides, it will impact how w
Hi Jialin,
well thats no hard requirement... ist totally fine if things come in that way
from time to time : )
As I'm so new to IoTDB I'm just still trying to understand whats the user group
currently and who drives feature ideas and stuff : )
I hope that we start soon with using IoTDB and then
Hi,
I think this is one oft he most important discussion to make it easily
accessible to users.
As Xiangdong states, we have to make it comfortable for users to map to
relational schemes.
And I agree that there are use cases for both, so probably really just provide
both.
Julian
Am 07.09.19
Hi,
This issue is to let user directly uses spark to read data in IoTDB for
analyzing.
This function can be done in many ways in IoTDB:
(1) Storing all TsFiles (data files) and other files (system files, WALs) on
HDFS, then use spark-tsfile to read TsFiles on HDFS.
(2) Storing only TsFiles on
