How to effectively use InfluxDB

FAQs
5
  • An InfluxDB measurement is similar to an SQL database table.
  • InfluxDB tags are like indexed columns in an SQL database.
  • InfluxDB fields are like unindexed columns in an SQL database.
  • InfluxDB points are similar to SQL rows.

So I have a database called domotica with the following measurements:
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  • The environment measurement contains all of my sensor data
  • I have a couple of tags: location and type
    • Location tags are real places such as "Kitchen"
    • type tags are sensor measurement types such as "Temperature", "Humidity", "Light", etc.
  • I typically have only 1 field called value

Typically a tag will contain text, a field will contain a number. Try to make sure you get that right because correcting the data type of a field is a right pain.

Here are some example retention policies

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You may wish to accumulate long-term data into another measurement within your database with a continuous query such as:

CREATE CONTINUOUS QUERY cq_60min ON domotica BEGIN SELECT mean(value) AS value, max(value), min(value), max(value) - min(value) AS range INTO domotica.one_week.env_daily FROM domotica.twenty_four_hours.environment GROUP BY location, type, time(1h) END

Which summarises the 1 minute sensor values from domotica.twenty_four_hours.environment which are kept in that measurement for 1 week - into hourly values in domotica.one_week.env_daily, keeping average, max and min values for each 1hr time period.