mirror of
https://github.com/home-assistant/home-assistant.io.git
synced 2025-05-03 09:38:59 +00:00
88d890aa46
The query with pg_size_pretty returns the value as a string, that way you can’t have a nice chart or make value comparison. Inserted new query to return value as number.
102 lines
3.1 KiB
Markdown
102 lines
3.1 KiB
Markdown
---
|
|
layout: page
|
|
title: "SQL Sensor"
|
|
description: "Instructions how to integrate SQL sensors into Home Assistant."
|
|
date: 2018-02-03 00:22
|
|
sidebar: true
|
|
comments: false
|
|
sharing: true
|
|
footer: true
|
|
logo: sql.png
|
|
ha_category: Sensor
|
|
ha_release: 0.63
|
|
---
|
|
|
|
The `SQL` sensor platform enables you to use values from an [SQL](https://en.wikipedia.org/wiki/SQL) database supported by the [sqlalchemy](https://www.sqlalchemy.org) library, to populate a sensor state (and attributes).
|
|
This can be used to present statistics about Home Assistant sensors if used with the recorder component database. It can also be used with an external data source.
|
|
|
|
To configure this sensor, you need to define the sensor connection variables and a list of queries to your `configuration.yaml` file. A sensor will be created for each query:
|
|
|
|
To enable it, add the following lines to your `configuration.yaml`:
|
|
|
|
{% raw %}
|
|
```yaml
|
|
# Example configuration.yaml entry to monitor hass database size in MySQL
|
|
sensor:
|
|
- platform: sql
|
|
db_url: mysql://user:password@localhost/hass
|
|
queries:
|
|
- name: HASS DB size
|
|
query: 'SELECT table_schema "database", Round(Sum(data_length + index_length) / 1024, 1) "value" FROM information_schema.tables WHERE table_schema="hass" GROUP BY table_schema;'
|
|
column: 'value'
|
|
unit_of_measurement: kB
|
|
```
|
|
{% endraw %}
|
|
|
|
{% configuration %}
|
|
db_url:
|
|
description: The URL which points to your database. See [supported engines](/components/recorder/#custom-database-engines).
|
|
required: false
|
|
default: Defaults to the recorder db_url.
|
|
type: string
|
|
queries:
|
|
description: List of your queries.
|
|
required: true
|
|
type: map
|
|
keys:
|
|
name:
|
|
description: The name of the sensor.
|
|
required: true
|
|
type: string
|
|
query:
|
|
description: An SQL QUERY string, should return 1 result at most.
|
|
required: true
|
|
type: string
|
|
column:
|
|
description: The field name to select.
|
|
required: true
|
|
type: string
|
|
unit_of_measurement:
|
|
description: Defines the units of measurement of the sensor, if any.
|
|
required: false
|
|
type: string
|
|
value_template:
|
|
description: Defines a template to extract a value from the payload.
|
|
required: false
|
|
type: template
|
|
{% endconfiguration %}
|
|
|
|
## {% linkable_title Examples %}
|
|
|
|
In this section you find some real life examples of how to use this sensor.
|
|
|
|
### {% linkable_title Current state of an entity %}
|
|
|
|
This example shows the previously *recorded* state of sensor *abc123*.
|
|
|
|
```sql
|
|
SELECT * FROM states WHERE entity_id = 'sensor.abc123' ORDER BY id DESC LIMIT 2
|
|
```
|
|
|
|
Note that the SQL sensor state corresponds to the last row of the SQL resultset.
|
|
|
|
### {% linkable_title Previous state of an entity %}
|
|
|
|
This example only works with *binary_sensors*:
|
|
|
|
```sql
|
|
SELECT * FROM states WHERE entity_id='binary_sensor.xyz789' GROUP BY state ORDER BY last_changed DESC LIMIT 1
|
|
```
|
|
|
|
### {% linkable_title Database size in Postgres %}
|
|
|
|
```yaml
|
|
- platform: sql
|
|
db_url: postgresql://user:password@host/dbname
|
|
queries:
|
|
- name: db_size
|
|
query: "SELECT (pg_database_size('dsmrreader')/1024/1024) as db_size;"
|
|
column: "db_size"
|
|
unit_of_measurement: MB
|
|
```
|