Connecting to ClickHouse

Connection Steps

Please follow the steps below to connect to the ClickHouse data source.

1. Click "New Data Connection" in the upper right corner of the data connection page.

2. Select the ClickHouse data source from the data source types.

3. Fill in the required parameters for the data source connection as prompted.

   Connection Configuration Information Description

   Field	Description
   Name	The name of the connection. Required and unique within the user.
   Host	The address of the database. If the URL field is filled in, the URL will take precedence.
   Port	The port of the database. If the URL field is filled in, the URL will take precedence.
   Username	The username for the database.
   Password	The password for the database.
   Database	The name of the database.
   Max Connections	The maximum number of connections in the connection pool.
   Encoding	The encoding setting for the database connection.
   Prefer using database comment as dataset title	Prefer to display the table name or the table comment.
   URL	The JDBC URL of the database.
   Cluster	For output only. Output to the specified cluster. If this parameter is empty, only the local MergeTree table is written. If filled, a distributed table will be generated based on the local MergeTree table according to the cluster.
   Use Table Replicas for ClickHouse Output	For output only. Whether to use table replicas. If not using replicas, the table engine is MergeTree; if using replicas, the table engine is ENGINE = ReplicatedMergeTree('/clickhouse/tables/{database}/{table}/{shard}', '{replica}') order by %s settings allow_nullable_key=1
   ClickHouse Output Table Engine Template	Default is ENGINE = ReplicatedMergeTree('/clickhouse/tables/{database}/{table}/{shard}', '{replica}') order by %s settings allow_nullable_key=1. Users can also modify according to the format.
   join_use_nulls	Can be 0 or 1, affects the behavior of join.
   Hierarchical loading of schema and tables	Default is off. When enabled, schemas and tables are loaded hierarchically. Only schemas are loaded during connection, and you need to click the schema to load the tables under it.
   Query Timeout (seconds)	Default is 600. When the data volume is large, you can appropriately increase the timeout.
   Allow Write Operations	Indicates that this connection can be selected as an output connection in Data Integration and Batch Sync. You must have write permission to the database and pass verification before configuring this parameter.
   Support uploading files to specified path	Indicates the database name where the generated table is stored when creating a local file dataset. You must have write permission to the database and pass verification before configuring this parameter.
   Show only tables under specified database/schema	When this option is selected and the database field is not empty, only tables under the specified db will be displayed.

4. After filling in the parameters, click the Validate button to get the validation result (this checks the connectivity between HENGSHI SENSE and the configured data connection; you cannot add the connection if validation fails).

5. After validation passes, Allow Write Operations and Support uploading files to specified path will be enabled and can be optionally turned on.

6. Click Execute Preset Code to pop up the preset code for this data source, then click the execute button.

7. Click the Add button to add the ClickHouse connection.

Please note

1. Parameters marked with * are required; others are optional.
2. When connecting to a data source, you must execute the preset code. Failure to do so may result in certain functions being unavailable during data analysis. In addition, when upgrading from a version prior to 4.4 to 4.4, you need to execute the preset code for existing data connections in the system.

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Supported clickhouse Versions

21.2 and above