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Applies to: ✅ Azure Data Explorer
Returns query acceleration details of a specified external table or all external tables in the database.
This command is relevant to any external table of any type. For an overview of external tables, see external tables.
Permissions
You must have at least Database User, Database Viewer, Database Monitor to run these commands. For more information, see role-based access control.
Syntax
.show external tables details
.show external table TableName details
Learn more about syntax conventions.
Parameters
| Name | Type | Required | Description |
|---|---|---|---|
| TableName | string |
✔️ | The name of the external table to show. |
Returns
| Output parameter | Type | Description |
|---|---|---|
| TableName | string |
Name of external table |
| QueryAccelerationPolicy | string |
A JSON-serialization of the query acceleration policy that is set on the table. |
| QueryAccelerationState | string |
A JSON-serialization of the query acceleration status parameters. |
Query acceleration policy
| Column | Type | Description |
|---|---|---|
| IsEnabled | bool |
Indicates whether the external table has a query acceleration policy enabled. |
| Hot | timespan |
The hot period defined in the query acceleration policy. |
| MaxAge | timespan |
The maximum timespan from the last index refresh time that enables the external table to operate in accelerated mode. |
| HotWindows | datetime |
One or more optional time windows. Delta data files created within these time windows are accelerated. |
| ManagedIdentity | string |
The managed identity defined in the query acceleration policy. |
| HotDateTimeColumn | string |
The hot datetime column defined in the query acceleration policy. |
Query acceleration state
| Column | Type | Description |
|---|---|---|
| HotSize | long |
The total size on disk (in bytes) of artifacts accelerated due to the query acceleration policy. |
| CompletePercentage | double |
The percentage of artifacts that are accelerated, out of the total artifacts that are able to be accelerated. |
| PendingDataFilesSize | long |
The total size of artifacts that are pending acceleration. |
| PendingDataFilesCount | int |
The number of artifacts that are pending acceleration. |
| IsHealthy | string |
Indicated whether healthy or not health. |
| NotHealthyReason | string |
Describes the reason for query acceleration not being healthy. Empty if healthy. |
| LastUpdatedDateTime | datetime |
The last datetime when the internal representation of the table was successfully refreshed. |
| Latency | timespan |
The time in minutes since the last new data was added to your logical copy. |
Example
.show external table deltatable details
Output
| TableName | QueryAccelerationPolicy | QueryAccelerationState |
|---|---|---|
| deltatable | {"IsEnabled": true, "Hot": "365000.00:00:00", "MaxAge": "5m", "HotWindows":[{"MinValue":"2025-07-04","MaxValue":"2025-07-06"}]} | { "HotSize": 29454192, "CompletionPercentage": 75.0, "PendingArtifactSize": 21162035, "PendingArtifactCount": 3, "IsHealthy": false, "NotHealthyReason": "InaccessibleDeltaTable : Delta table does not exist", "LastUpdatedDateTime": "2025-04-03 13:38:00.1541537", "Latency": "26.00:58:12.8941033"} |