Anyone datalogging?

[tocan]

There are 2 things of use. Openplotter to use when i am on tour. And because the lack of chart information special for petrol stations and other things i for shure have OSM on the smartphone and did put the Video just for to show what i did bought for it. Instead of display. Next step because also here the most requests via PM is that people whish the sensors and the switch in a more easy way. And i did experiment for this reason with Alexa and Sonoff. It works fine with raspberry and is something easy to manage also for beginners but usability is not what i am looking for. I decide nothing to produce for alexa with the pi unless its running. But since 3 months i am aware all runs without any hardware and just with a browser.

So in fact for just a few coins i get switches and also Sensors to use with alexa. I can ask in general is there any water in the bilge and alexa can tell me how much. And than i can start from home to switsch on the bilge pump 3000 km away. Its just an example and relies just to yours phantasies what you like to do with it. But its simple and easy to install for everyone.

For Gyro and other data i plan to use the Openseamap Logger what cost just 30 Euros , is nmea compatible. Here i log data all the year. So i have with time the database i can share. Including the Water depth data all over the year. In fact it means the time openplotter have nearly nothing to do can be used and i do not see any problem to do such. Also Openplotter will not die on tour unless you use datalocking. Also i did look arround in the upcoming skills in Alexa and there are a lot of usefull marine skills available in english but not in german.

https://www.amazon.com/chadioo-Sailing-G...B01JYPXSFU

For the tech geecks like you maybee something like this. What i do with the games i play e.g. with alexa i try to give just ideas.

https://www.hackster.io/ufuk-arslan/alexaboat-7f1a7e Example include Rasberry as well. But whatever we discuss now is not sorted out.
Its my answer also to the yesterdays question to find an intrance to MQTT and node red. Ready made and documented things and easy to build up.

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I'm aware of the concept of time series databases. Our boats aren't exactly like the Queen Mary 2 so we won't produce terabytes of data. From my point of view most of the databases you can run on the pi like mysql, influxdb, etc. are slowing down the system. That's why I prefer rather logging data to a file/sqlite than having a database server in the background bothering my cpu. Certainly the data queries will take longer but my pi isn't kept busy constantly. I don't know why you would need two years of sensor data on your pi and why you need a good performance for the data analysis. And even if you want time series data of a long range for a graph it'll be one slow select query and that's it. The select query takes 80 instead of 10 milliseconds - pardon my French but I don't give a rat's ***. I won't sacrifice over all system performance for two or three slow queries it takes to get the  some data from bigger ranged time series.   
If you want to use openplotter and the pi for real time data analysis of big time series maybe you got the wrong software and hardware.

Very much agree with all of that. I played around with RRDtools for a while, which worked OK but was a bit clunky to work with. Sqlite does all that is needed taking little CPU time. Handy having it as just one file as well, you can copy across to a faster machine easily to back up or do some more intensive plotting/sql. I've had one running pretty much constantly since about august recording once a minute, file is around 22Meg.

Its nice you found yours solution but i am no more interest in sql database logging. That this is working i did publish in my blog . What i am interesting for is something you did drop for. i am interesting in a step by step guide of yours influx db logging with grafana  including the connection to  Signal K. There is no reason i think to hide what you did drop. Exact this work i am interesting for.