github.com/simpleiot/simpleiot@v0.18.3/docs/user/database.md (about)

     1  # Database Client
     2  
     3  The main [SIOT store](../ref/store.md) is SQLite. SIOT supports additional
     4  database clients for purposes such as storing time-series data.
     5  
     6  ## InfluxDB 2.x
     7  
     8  Point data can be stored in an InfluxDB 2.0 Database by adding a Database node:
     9  
    10  <img src="assets/image-20240319111031186.png" alt="image-20240319111031186" style="zoom:50%;" />
    11  
    12  The following InfluxDB tags are added to every point:
    13  
    14  - `node.id` (typically a UUID)
    15  - `node.type` (extracted from the type field in the edge data structure)
    16  - `node.description` (generated from the `description` point from the node)
    17  
    18  ### Custom InfluxDB Tags
    19  
    20  Additional tag tag points can be specified. The DB client will query and cache
    21  node points of these types for any point flowing through the system and then
    22  InfluxDB tags in the format: `node.<point type>.<point key>`. In the below
    23  example, we added a machine tag to the signal generator node generating the
    24  data.
    25  
    26  <img src="assets/image-20240319112828216.png" alt="image-20240319112828216" style="zoom:50%;" />
    27  
    28  When the `tag` field is specified in the database node, this `machine` tag is
    29  now added to the Influx tags for every sample.
    30  
    31  - `value` and `type` and fields from the point
    32  - `node.description` and `node.type` are automatically added
    33  - `node.tag.machine` got added because the `tag` point was added to the list of
    34    node points that get added as tags.
    35  
    36  ![image-20240319110846431](assets/image-20240319110846431.png)
    37  
    38  See the [Graphing documentation](graphing.md) for information on how to
    39  automatically map tags to graph labels.
    40  
    41  InfluxDB indexes tags, so generally there is not a huge cost to adding tags to
    42  samples as the long string is only stored once.
    43  
    44  ## Victoria Metrics
    45  
    46  Victoria Metrics
    47  [supports the InfluxDB v2](https://docs.victoriametrics.com/#how-to-send-data-in-influxdb-v2-format)
    48  line protocol; therefore, it can be used for numerical data. Victoria Metrics
    49  [does not support storing strings](https://stackoverflow.com/questions/66406899/does-victoriametrics-have-some-way-to-store-string-value-instead-float64).