222 questions
0
votes
1
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109
views
How TDengine downsampling queries
How to perform downsampling queries on TDengine? For example, the original frequency of data was once per second, but now we want to perform one query every 10 seconds
-1
votes
1
answer
100
views
how to insert a CSV file into TDengine?
The data is a CSV file with comma as separator and timestamp and string field value quoted by single quotes，how can i insert it into TDengine?
I am now using SQL to achieve that Single row or multiple ...
-1
votes
1
answer
42
views
Cannot able to get the data using rest api from TDengine cloud account
I got the 200 response succes but cannot able to get the response of my query. i want to show the data base available in the TDengine cloud account. And my query is SHOW DATABASES.
Anyone hlep me to ...
0
votes
1
answer
35
views
how to get the beginning, end, and duration of a TDengine window query?
Is there any keywords or pseudocolumns that can indicate the beginning, end, and duration of a TDengine window query?
I am using partitioned queries and windowed queries of TDengine,, as shown below:...
0
votes
1
answer
36
views
show table tags from foo.stb; DB error: syntax error near ".stb;"
I need to view all the tag information under a super table, but when I write it like this, it gives an error. Can someone explain it to me?
taos> use foo;
Query OK, 0 row(s) affected (0.002940s)
...
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-2
votes
1
answer
44
views
Does TDengine support writing a comment for each field?
Does TDengine support writing a comment for each field?
How to write statements that support SQL?
Can TDengine only store change data, that is, if the collected data is the same as the previous time ...
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-3
votes
1
answer
86
views
How does it compare to other real-time data processing systems like Apache Kafka or Apache Flink?
Can TDengine support real-time data streaming and processing? How does it compare to other real-time data processing systems like Apache Kafka or Apache Flink?
In practice, we generate large real-time ...
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0
votes
1
answer
120
views
How does TDengine handle data replication and high availability in a distributed environment?
TDengine provides several mechanisms to handle data replication and high availability in a distributed environment:
Replication: TDengine supports data replication between nodes in a cluster. When a ...
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-4
votes
1
answer
161
views
Out of dnodes (0.000000s) [closed]
The TDengine fails to CREATE a DATABASE. CREATE DATABASE power KEEP 365 DURATION 10 BUFFER 16 WAL_LEVEL 1;
This error occurs when I try to create a database. How do I fix it，I can fix it.If you have ...
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-1
votes
1
answer
338
views
OSError: libtaos.so: cannot open shared object file: No such file or directory
I have this error exception when installing TDengine. Have any of you encountered it before?
I tried to install the application, but he raised this exception: OSError: libtaos.so: cannot open shared ...
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0
votes
1
answer
133
views
Get the timestamp of max value in TDengine
I'm trying to downsample with interval in TDengine.
I have a statement:
select _wstart, max(val) max_val, min(val) min_val from d1001 interval(5s);
enter image description here
You can see in the ...
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0
votes
1
answer
41
views
No valid function in window query when using time window in TDengine
I'm trying to create a stream in TDengine.
The following statement is ok:
Select count(*),first(_ts),last_row(_ts),_value,devicecode from yxzt partiton by devicecode state_window(_value);
However, ...
- 1
0
votes
1
answer
81
views
fail to delete data from TDengine
I want to delete some data from a table.
First, I executed the following sql:
select count(1) from dclm_device.device_int where identifier = "water_level";
I can see "Query OK, 1 rows ...
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0
votes
1
answer
91
views
An error occurred while transferring data from TDengine 2.4 to TDengine 3.0 with taosdump
taosdump.3340632973591 is from TDengine 2.4.
When I try to recover data in TDengine 3.0 ,I have a problem.
Here's the code
root@nofeel:~# taosdump -i taosdump.3340632973591
taosdump: symbol lookup ...
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0
votes
1
answer
87
views
Does TDengine support to modify the TTL afterwards?
I create a super table with the following statement:
CREATE STABLE `gps` (`st` TIMESTAMP, `loc_type` INT, `access_address` VARCHAR(200), `t` TIMESTAMP, `lat` FLOAT, `lng` FLOAT, `alt` FLOAT, `dir` ...
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