34 lines
1.1 KiB
Markdown
34 lines
1.1 KiB
Markdown
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Use the [`distinct_cache()` SQL function](/influxdb3/version/reference/sql/functions/cache/#distinct_cache)
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in the `FROM` clause of an SQL `SELECT` statement to query data from the
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Distinct Value Cache (DVC).
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> [!Important]
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> You must use SQL to query the DVC.
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> InfluxQL does not support the `distinct_cache()` function.
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`distinct_cache()` supports the following arguments:
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- **table_name**: _({{< req >}})_ The name of the table the DVC is associated with
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formatted as a string literal.
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- **cache_name**: The name of the DVC to query formatted as a string literal.
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This argument is only required if there is more than one DVC associated with
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the specified table.
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```sql
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SELECT * FROM distinct_cache('table_name', 'cache_name')
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```
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You can use other [SQL clauses](/influxdb3/version/reference/sql/#statements-and-clauses)
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to modify query results. For example, you can use the `WHERE` clause to return
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the distinct tag values associated with another distinct tag value:
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```sql
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SELECT
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city
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FROM
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distinct_cache('wind_data', 'windDistinctCache')
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WHERE
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country = 'Spain'
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```
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