.alter cluster caching policy command
Applies to: ✅ Azure Data Explorer
Changes the cluster's caching policy. To speed up queries, data is cached on processing nodes, SSD, or even in RAM. The caching policy allows your cluster to describe the data artifacts that it uses, so that more important data can take priority.
Permissions
You must have AllDatabasesAdmin permissions to run this command.
Syntax
.alter cluster policy caching PolicyParameter
Learn more about syntax conventions.
Parameters
| Name | Type | Required | Description |
|---|---|---|---|
| PolicyParameter | string |
✔️ | One or more policy parameters. For parameters, see caching policy. |
Returns
Returns a JSON representation of the policy.
Example
The following example sets the caching policy to include the last 30 days.
.alter cluster policy caching hot = 30d
Output
| PolicyName | EntityName | Policy | ChildEntities | EntityType |
|---|---|---|---|---|
| CachingPolicy | {"DataHotSpan": { "Value": "30.00:00:00" }, "IndexHotSpan": { "Value": "30.00:00:00"}} |
Define hot-cache windows
This command sets the caching policy to include the last 30 days and additional data from January and April 2021.
.alter cluster policy caching
hot = 30d,
hot_window = datetime(2021-01-01) .. datetime(2021-02-01),
hot_window = datetime(2021-04-01) .. datetime(2021-05-01)
Output
| PolicyName | EntityName | Policy | ChildEntities | EntityType |
|---|---|---|---|---|
| CachingPolicy | {"DataHotSpan": { "Value": "30.00:00:00" }, "IndexHotSpan": { "Value": "30.00:00:00" },"HotWindows": [{ "MinValue": "2021-01-01T00:00:00Z", "MaxValue": "2021-02-01T00:00:00Z" }, { "MinValue": "2021-04-01T00:00:00Z", "MaxValue": "2021-05-01T00:00:00Z" }]} |