Overview
This node integrates with a ClickHouse database, allowing users to either execute SQL queries or insert rows into a specified table. It is particularly useful for workflows that require interaction with large-scale analytical databases where fast data ingestion and querying are essential.
For the Insert operation, the node takes input data items and inserts them as rows into a specified ClickHouse table. This is beneficial when you want to automate data ingestion from various sources into ClickHouse for further analysis or reporting.
Example use case: Automatically inserting processed data from previous workflow steps into a ClickHouse table named "product" for real-time analytics.
Properties
| Name | Meaning |
|---|---|
| Table name | The name of the ClickHouse table where the input data rows will be inserted. You can use expressions to dynamically set this value. |
Output
- For the Insert operation, the node does not produce any JSON output data because it performs an insertion action without returning rows.
- If the node were used in the Query operation (not requested here), it would output an array of JSON objects representing each row returned by the query.
- The node does not output binary data.
Dependencies
- Requires a ClickHouse database accessible via network.
- Needs credentials including host URL, database name, username, and password to connect to ClickHouse.
- Uses the official
@clickhouse/clientlibrary to interact with the database. - No additional environment variables or n8n configurations beyond providing valid ClickHouse credentials are necessary.
Troubleshooting
- Connection errors: If the node fails to connect, verify that the ClickHouse server URL, database name, username, and password are correct and that the server is reachable.
- Insertion failures: Ensure the input data matches the schema of the target table. Mismatched column names or types can cause errors.
- Empty input data: If no input items are provided, the node will attempt to insert an empty array, which may result in no action or an error depending on ClickHouse settings.
- Permission issues: The user must have INSERT privileges on the specified table.
- Common error messages will relate to connection failures, authentication errors, or SQL exceptions during insertion. Checking the exact error message and verifying credentials and data format usually resolves these issues.