35 lines
1.0 KiB
Markdown
35 lines
1.0 KiB
Markdown
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Use the [`last_cache()` SQL function](/influxdb3/version/reference/sql/functions/cache/#last_cache)
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in the `FROM` clause of an SQL `SELECT` statement to query data from the
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Last Value Cache (LVC).
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> [!Important]
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> You must use SQL to query the LVC.
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> InfluxQL does not support the `last_cache()` function.
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`last_cache()` supports the following arguments:
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- **table_name**: _({{< req >}})_ The name of the table the LVC is associated with
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formatted as a string literal.
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- **cache_name**: The name of the LVC to query formatted as a string literal.
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This argument is only required if there is more than one LVC associated with the specified
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table.
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```sql
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SELECT * FROM last_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 last value for a specific tag set:
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```sql
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SELECT
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room,
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temp
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FROM
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last_cache('home', 'homeCache')
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WHERE
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room = 'Kitchen'
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```
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