database schema - InfluxDB : single or multiple measurement -


i'm beginner influxdb , after reading schema design documentation question remain.

how decide if should use 1 measurement multiple fields or multiple measurement single field ?

i have multiple iot device send every datas minute (temperature,humidity, pressure). datas have exact same timestamp.

so wondering if d rather create 1 measurement : 

    timestamp,iotid,temperature,humidity,pressure -------------------------------------------------     1501230195,iot1,70,         45,      850

or 3 measurements (one each value) , same tags 1 field in ?

timestamp,iotid,temperature ----------------------------     1501230195,iot1,70  timestamp,iotid,humidity -------------------------     1501230195,iot1,45  timestamp,iotid,pressure -------------------------     1501230195,iot1,850

query-wise, retrieve 1 value 3 @ same time.

there no right or wrong go either schema design going 1 measurement 1 field value more appropriate approach.

why?

storing multiple field values measurement relational database thing. is, measurement should not seen database table different thing.

a measurement should reserved explicitly describing type of data, temperature or cpu usage.

if design our schema using one field value per measurement can describe data in real english like;

at point in time, temperature measured data value=30. noticed term used here, point, data , measurement.

whereas if put multiple field values specific measurement find difficult present data in real english.

influxdb time series database obvious should time-series way.

also, of time series data measured down precision level of micro-seconds. in such fine grain timing, milliseconds unlikely set of data share same timing. hence designing 1 measurement containing sequence of data point better choice.


Comments

Post a Comment

Popular posts from this blog

php - Vagrant up error - Uncaught Reflection Exception: Class DOMDocument does not exist -

i've set bento/ubuntu-16.04 vagrant box using php 5.6, , getting following error quite few times when try , run shell script: "uncaught reflection exception: class domdocument not exist". i've tried adding following top of script (not together), each no success: "sudo apt-get install php5.6-xml", "sudo apt-get install php5-xml", "sudo apt-get install php-dom" i've tried resetting server "sudo service apache2 restart". does have suggestions?
Read more

vue.js - Create hooks for automated testing -

Image
qa guys complained can't automate frontend testing. because our html looks same outside. lazy hack did this <template> <div :role="$options.name"> ... </div> </template> <script> export default { name: 'vmcomponentname' } </script> which takes name script , applies html. in browser get: <div role="vmcomponentname"> ... </div> line :role="$options.name" goes in every component. is there dry er solutions? please share. additional details i'll explain in details looking for. imagine have vmusercreate form creates user. test case can create user . to automatically test without role, have use following selector: .wrapper > .wrapper > .wrapper > .submit-button the test extremely brittle (will break lot). if use roles can use [role="vmusercreateform"] .submit-button selector. many folds less brittle. so basically, i'm ...
Read more

Add new key value to json node in java -

i have json file : { "id":1, "name":"abc", "addressdetails": { "city":"newyork" } } i wanted add 1 more key-value ("pincode" : "414141") node 'addressdetails'. i tried using : objectmapper mapper = new objectmapper(); jsonnode root = mapper.readtree(new file("d://test.json")); objectnode node = mapper.createobjectnode(); node.with("addressdetails").put("pincode", "414141"); but it's not getting added, there way can ? you can try you should modify file path objectmapper mapper = new objectmapper(); objectnode nodes = mapper.readvalue(new file("d:\\test.txt"), objectnode.class); nodes.with("addressdetails").put("pincode", "414141"); mapper.writer().writevalue(new file("d:\\test.txt"), nodes);
Read more