InfluxDB Times Series Data Platform

InfluxDB is a temporal database.

Data Elements for InfluxDB

https://docs.influxdata.com/influxdb/v2.1/reference/key-concepts/data-elements/

• timestamp

  All data stored in InfluxDB has a _time column that stores timestamps.

• measurement

  The _measurement column shows the name of the measurement. Measurement names are strings. A measurement acts as a container for tags, fields, and timestamps.

• field

  A field includes a field key stored in the _field column and a field value stored in the _value column. A measurement requires at least one field.

• field key

  A field key is a string that represents the name of the field. In the sample data above, bees and ants are field keys.

• field value

  A field value represents the value of an associated field. Field values can be strings, floats, integers, or booleans. The field values in the sample data show the number of bees at specified times: 23, and 28 and the number of ants at a specified time: 30 and 32.

• field set

  A field set is a collection of field key-value pairs associated with a timestamp. A measurement requires at least one field. The sample data includes the following field sets:

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  census bees=23i,ants=30i 1566086400000000000 census bees=28i,ants=32i 1566086760000000000 ----------------- Field set

• tags

  Tags include tag keys and tag values that are stored as strings.

• tag key

  The tag keys in the sample data are location and scientist.

• tag value

  The tag key location has two tag values: klamath and portland. The tag key scientist also has two tag values: anderson and mullen.

• tag set

  The collection of tag key-value pairs make up a tag set. The sample data includes the following four tag sets:

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  location = klamath, scientist = anderson location = portland, scientist = anderson location = klamath, scientist = mullen location = portland, scientist = mullen

• series

  A series key is a collection of points that share a measurement, tag set, and field key. For example, the sample data includes two unique series keys.

  _measurement	tag set	_field
  census	location=klamath,scientist=anderson	bees
  census	location=portland,scientist=mullen	ants

  A series includes timestamps and field values for a given series key. From the sample data, here’s a series key and the corresponding series.

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  # series key census,location=klamath,scientist=anderson bees # series 2019-08-18T00:00:00Z 23 2019-08-18T00:06:00Z 28

InfluxDB library with C#

The InfluxDB library with C# support is officially maintained: influxdb-client-csharp(https://github.com/influxdata/influxdb-client-csharp)

• The official library does not support the SQL language, but uses the official proposed Flux language.

• InfluxDB can query data using InfluxQL and Flux as well as api.

• The InfluxQL language is very similar to the SQL language, but it seems to be used only for for api query usage.

• InfluxQL and Flux are basically functionally equivalent. Only the code looks different.(https://docs.influxdata.com/influxdb/v2.1/reference/syntax/flux/flux-vs-influxql/#influxql-and-flux-parity)

Flux

Flux is an open source functional data scripting language(https://docs.influxdata.com/flux/v0.x/)

• show databases

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  buckets()

• show tables

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  import "influxdata/influxdb/schema" schema.measurements(bucket: "bucketsName")

• show columns (You need to add _time and _value manually)

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  import "influxdata/influxdb/sample" sample.data(set: "sampleTableName") |> keys() |> keep(columns: ["_value"]) |> distinct()

Data Type

Connection configuration

https://github.com/influxdata/influxdb-client-csharp/tree/master/Client#client-connection-string

A client can be constructed using a connection string that can contain the InfluxDBClientOptions parameters encoded into the URL.

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connectionString = "http://localhost:8086?token=myToken&org=myOrg"

The following options are supported:

The timeout supports ms, s and m as unit. Default is milliseconds.