1.1 KiB
1.1 KiB
Use the distinct_cache()
SQL function
in the FROM
clause of an SQL SELECT
statement to query data from the
Distinct Value Cache (DVC).
[!Important] You must use SQL to query the DVC. InfluxQL does not support the
distinct_cache()
function.
distinct_cache()
supports the following arguments:
- table_name: ({{< req >}}) The name of the table the DVC is associated with formatted as a string literal.
- cache_name: The name of the DVC to query formatted as a string literal. This argument is only required if there is more than one DVC associated with the specified table.
SELECT * FROM distinct_cache('table_name', 'cache_name')
You can use other SQL clauses
to modify query results. For example, you can use the WHERE
clause to return
the distinct tag values associated with another distinct tag value:
SELECT
city
FROM
distinct_cache('wind_data', 'windDistinctCache')
WHERE
country = 'Spain'