ClickHouse/docs/en/engines/table-engines/integrations/azure-queue.md
2024-10-22 17:54:20 +02:00

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---
slug: /en/engines/table-engines/integrations/azure-queue
sidebar_position: 181
sidebar_label: AzureQueue
---
# AzureQueue Table Engine
This engine provides an integration with [Azure Blob Storage](https://azure.microsoft.com/en-us/products/storage/blobs) ecosystem, allowing streaming data import.
## Create Table {#creating-a-table}
``` sql
CREATE TABLE test (name String, value UInt32)
ENGINE = AzureQueue(...)
[SETTINGS]
[mode = '',]
[after_processing = 'keep',]
[keeper_path = '',]
...
```
**Engine parameters**
`AzureQueue` parameters are the same as `AzureBlobStorage` table engine supports. See parameters section [here](../../../engines/table-engines/integrations/azureBlobStorage.md).
**Example**
```sql
CREATE TABLE azure_queue_engine_table (name String, value UInt32)
ENGINE=AzureQueue('DefaultEndpointsProtocol=http;AccountName=devstoreaccount1;AccountKey=Eby8vdM02xNOcqFlqUwJPLlmEtlCDXJ1OUzFT50uSRZ6IFsuFq2UVErCz4I6tq/K1SZFPTOtr/KBHBeksoGMGw==;BlobEndpoint=http://azurite1:10000/devstoreaccount1/data/')
SETTINGS
mode = 'unordered'
```
## Settings {#settings}
The set of supported settings is the same as for `S3Queue` table engine, but without `s3queue_` prefix. See [full list of settings settings](../../../engines/table-engines/integrations/s3queue.md#settings).
To get a list of settings, configured for the table, use `system.s3_queue_settings` table. Available from `24.10`.
## Description {#description}
`SELECT` is not particularly useful for streaming import (except for debugging), because each file can be imported only once. It is more practical to create real-time threads using [materialized views](../../../sql-reference/statements/create/view.md). To do this:
1. Use the engine to create a table for consuming from specified path in S3 and consider it a data stream.
2. Create a table with the desired structure.
3. Create a materialized view that converts data from the engine and puts it into a previously created table.
When the `MATERIALIZED VIEW` joins the engine, it starts collecting data in the background.
Example:
``` sql
CREATE TABLE azure_queue_engine_table (name String, value UInt32)
ENGINE=AzureQueue('<endpoint>', 'CSV', 'gzip')
SETTINGS
mode = 'unordered';
CREATE TABLE stats (name String, value UInt32)
ENGINE = MergeTree() ORDER BY name;
CREATE MATERIALIZED VIEW consumer TO stats
AS SELECT name, value FROM azure_queue_engine_table;
SELECT * FROM stats ORDER BY name;
```
## Virtual columns {#virtual-columns}
- `_path` — Path to the file.
- `_file` — Name of the file.
For more information about virtual columns see [here](../../../engines/table-engines/index.md#table_engines-virtual_columns).