Use template for query in SQL

source/_integrations/sql.markdown

@@ -81,7 +81,7 @@ sql:
     query:
       description: An SQL QUERY string, should return 1 result at most.
       required: true
-      type: string
+      type: template
     column:
       description: The field name to select.
       required: true
@@ -149,16 +149,18 @@ The `sql.query` action returns a list of rows, where each row is a dictionary of
 #### Data type conversion
 
 The data returned by the database is converted to be compatible with the action response. The following conversions are applied:
+
 - `Decimal` types are converted to floats.
 - `Date` and `Datetime` objects are converted to ISO 8601 formatted strings.
 - `bytes` and `bytearray` are converted to a hexadecimal string prefixed with `0x`.
 - All other basic types (string, integer, float, boolean) are returned as is.
 
 #### Example
 
-Example of calling the `sql.query` action in an automation:
+##### Example of calling the `sql.query` action in an automation:
 
 {% raw %}
+
 ```yaml
 action: sql.query
 data:
@@ -178,11 +180,13 @@ data:
       3;
 response_variable: sun_history
 ```
+
 {% endraw %}
 
 This would return a result similar to this, which will be stored in the `sun_history` variable:
 
 {% raw %}
+
 ```yaml
 result:
   - state: below_horizon
@@ -245,6 +249,48 @@ LIMIT
 
 Use `state` as column for value.
 
+### Amount of state changes since using a template
+
+This example shows the amount of state changes of the sensor `sensor.temperature_in`
+using another sensor's state to provide the time window.
+
+```yaml
+sensor:
+  - platform: random
+    name: Temperature in
+    unit_of_measurement: "°C"
+```
+
+The query will look like this:
+
+{% raw %}
+
+```sql
+SELECT
+  count(state) as changes
+FROM
+  (
+    SELECT
+      states.state
+    FROM
+      states
+    WHERE
+      metadata_id = (
+        SELECT
+          metadata_id
+        FROM
+          states_meta
+        WHERE
+          entity_id = 'sensor.temperature_in'
+      )
+      AND last_updated_ts >= strftime('%s','{{ states("sensor.datetime_helper") }}')
+  )
+```
+
+{% endraw %}
+
+Use `changes` as column for value.
+
 ### Previous state of an entity
 
 Based on previous example with temperature, the query to get the former state is :
@@ -275,6 +321,7 @@ WHERE
       1
   );
 ```
+
 Use `state` as column for value.
 
 ### State of an entity x time ago