InfluxDB #1 | Overview

    1. Database  Comments

Introduction

  • Time Series DB (TSDB) : a DB optimized for time-stamped or time series data.
    • ex) server metrics, network data, sensor data, …

1. Data Elements

| _time                | _measurement | location | scientist | _field | _value |
| -------------------- | ------------ | -------- | --------- | ------ | ------ |
| 2019-08-18T00:00:00Z | census       | klamath  | anderson  | bees   | 23     |
| 2019-08-18T00:00:00Z | census       | portland | mullen    | ants   | 30     |
| 2019-08-18T00:06:00Z | census       | klamath  | anderson  | bees   | 28     |
| 2019-08-18T00:06:00Z | census       | portland | mullen    | ants   | 32     |

  • Timestamp (_time) :

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

  • Measurement (_measurement) :

    • acts as a container for tags, fields, and timestamps (as ‘Table’ in RDBMS)

  • Tags (location, scientist):

    • Tags are indexed
      • Tags are optional. You don’t need tags in your data structure. But InfluxDB indexes tags, the query engine doesn’t need to scan every record in a bucket to locate a tag value.
    • tag key : location, scientist in sample data
    • tag value : The tag key location has two tag values : klamath and portland
    • tag set : The collection of tag key value pairs
      • location=klamath, scientis=anderson …

  • Field (_field) :

    • field key : the name of the field
    • field value : strings, floats, integers, or booleans.
    • field set : A collection of field key-value pairs associated with a timestamp. The sample data includes two field sets:
      • census bees=23i,ants=30i 1566086400000000000
      • census bees=28i,ants=32i 1566086760000000000

  • Series

    • series key : is a unique combinaion of measurement, tag set, and field key.
    • series (value) : includes timestamps and field values for a given series key

  • Point

    • includes the series key, a field value, and a timestamp
      • 2019-08-18T00:00:00Z census ants 30 portland mullen

  • Bucket

    • combines the concept of database and a retention period

  • Organization

    • a workspace for a group of users : All dashboards, tasks, buckets, and users belong to an organization

2. Write Data - Best Practicies

  • 2.4 Handle duplicate data points
    • InfluxDB identifies unique data points by their measurement, tag set, and timestamp
    • To preserve duplicate points
      • (1) Add an arbitraty tag with unique values so InfluxDB reads the dups as unique
      • (2) Increment the timestamp : by a nanosecond to enforce the uniqueness of each point.

References