Go to advanced search

by msd
Thu Feb 25, 2016 8:32 am
Forum: Automation, sensing and robotics
Topic: How to create a sensor database with IBM Informix - Part 1
Replies: 12
Views: 5436

Re: How to create a sensor database with IBM Informix - Part

By aggregation I mean using a VTI to be able to select all sensor data at once and using the AggregateBy function: EXECUTE PROCEDURE TSCreateExpressionVirtualTab( 'sensor_data_1h_avg', 'sensor_ts', 'AggregateBy("avg($value)", "ts_1hour", sensor_values, 0, $ts_begin_time, $ts_end_time)', 'sensor_t', ...
by msd
Wed Feb 24, 2016 4:56 pm
Forum: Automation, sensing and robotics
Topic: How to create a sensor database with IBM Informix - Part 1
Replies: 12
Views: 5436

Re: How to create a sensor database with IBM Informix - Part

Hi Alexander, thank you for your patience. Regarding adding a primary key: it does not make it faster, but it's ok, it's a RPi! At the end I wanted to get data from all sensors at once, and I used a VTI to do that aggregating data. I averaged over 1h or 1d for longer time ranges (1 week or more). It...
by msd
Wed Feb 24, 2016 8:14 am
Forum: Automation, sensing and robotics
Topic: How to create a sensor database with IBM Informix - Part 1
Replies: 12
Views: 5436

Re: How to create a sensor database with IBM Informix - Part

Please try the following SELECT statement and let me know how it performs: SELECT GetLastElem(sensor_values).value from sensor_ts where sensor_id = 'Sensor03' Hi Alexander, this works great, exactly as expected. Thank you! Is there any function to get e.g. last 24 hours of sensor data, other than j...
by msd
Tue Feb 23, 2016 4:00 pm
Forum: Automation, sensing and robotics
Topic: How to create a sensor database with IBM Informix - Part 1
Replies: 12
Views: 5436

Re: How to create a sensor database with IBM Informix - Part

it would be great, if you could share how your (intended) query looks like, how do you execute your query (e.g. via dbaccess or the REST API) and what would you like to achieve with your query. Also do you run your tests on a RPi or on a RPi2? Hi, yes sorry for not giving a better explanation: I ha...
by msd
Tue Feb 23, 2016 7:57 am
Forum: Automation, sensing and robotics
Topic: How to create a sensor database with IBM Informix - Part 1
Replies: 12
Views: 5436

Re: How to create a sensor database with IBM Informix - Part

Hi Alexander,

selecting data on a RPi1 from sensor_data table is very slow, even when reading a single value, do you know the reason why is it like that?

BR
Marco
by msd
Sun Feb 21, 2016 10:03 am
Forum: Automation, sensing and robotics
Topic: A SQL database for sensor and JSON data on Raspian
Replies: 17
Views: 13119

Re: A SQL database for sensor and JSON data on Raspian

Hi,

thanks a lot for this guide Alexander!!

Could help me setting up the REST/JSON listener?

BR
Marco

Go to advanced search