75 lines
2.9 KiB
Markdown
75 lines
2.9 KiB
Markdown
---
|
|
title: Manage Last Value Caches with InfluxDB 3 Explorer
|
|
list_title: Manage Last Value Caches
|
|
description: >
|
|
Use InfluxDB 3 Explorer to manage Last Value Caches in an InfluxDB 3 instance
|
|
or cluster.
|
|
menu:
|
|
influxdb3_explorer:
|
|
name: Last Value Caches
|
|
parent: Manage caches
|
|
weight: 101
|
|
related:
|
|
- /influxdb3/enterprise/admin/last-value-cache/, Manage the Last Value Cache in InfluxDB 3 Enterprise
|
|
- /influxdb3/core/admin/last-value-cache/, Manage the Last Value Cache in InfluxDB 3 Core
|
|
---
|
|
|
|
Use InfluxDB 3 Explorer to manage Last Value Caches (LVCs) in an InfluxDB 3
|
|
instance or cluster. To navigate to the **Last Value Cache management page**, in
|
|
the left navigation bar, select **Configure** > **Caches**.
|
|
|
|
- [View Last Value Caches](#view-last-value-caches)
|
|
- [Create a Last Value Cache](#create-a-last-value-cache)
|
|
- [Query a Last Value Cache](#query-a-last-value-cache)
|
|
- [Delete a Last Value Cache](#delete-a-last-value-cache)
|
|
|
|
## View Last Value Caches
|
|
|
|
To view LVCs associated with a database, navigate to the
|
|
**Last Value Cache management page** and select the database from the
|
|
**Select Database** dropdown menu. The page lists all LVCs associated with the
|
|
selected database.
|
|
|
|
## Create a Last Value Cache
|
|
|
|
On the **Last Value Cache management page**:
|
|
|
|
1. Click **+ Create Cache**.
|
|
2. Provide the following:
|
|
|
|
- **Cache name**: A unique name for the cache.
|
|
- **Database**: The database the cache is associated with.
|
|
- **Table**: The target table for the cache. As data is written to the table,
|
|
it populates the cache.
|
|
_You must select a database before you can select a table._
|
|
- **Key columns**: Select string-typed column columns to use as the primary
|
|
key for the cache. These are typically InfluxDB tags, but you can also use
|
|
fields. Each unique combination of key column values represents a distinct
|
|
series. LVCs cache N (count) values per series.
|
|
- **Value columns**: Select columns to cache values for. These are
|
|
typically InfluxDB fields, but can also be tags. If no columns are
|
|
selected as value columns, all non-key columns are used as value columns
|
|
(excluding `time`).
|
|
- **Count**: Specify the number of recently written values to cache per series.
|
|
|
|
> [!Note]
|
|
> Higher cardinality (more unique series) in an LVC increases memory usage.
|
|
> Be selective about key columns and the number of values to cache per
|
|
> series to optimize performance.
|
|
|
|
3. Click **Create**.
|
|
|
|
## Query a Last Value Cache
|
|
|
|
Use the `last_cache` SQL function to query an LVC. For more information, see
|
|
[Query a Last Value Cache](/influxdb3/enterprise/admin/last-value-cache/query/).
|
|
|
|
## Delete a Last Value Cache
|
|
|
|
On the **Last Value Cache management page**:
|
|
|
|
1. Select the database associated with the cache you want to delete from the
|
|
**Select Database** dropdown menu.
|
|
2. In the **Active Caches** table, click the {{% icon "trash" %}} icon next to
|
|
the cache you want to delete.
|