Clickhouse.md

Clickhouse

Clickhouse source connector

Support Those Engines

Spark
Flink
SeaTunnel Zeta

Key Features

• batch
• stream
• exactly-once
• column projection
• parallelism
• support user-defined split

supports query SQL and can achieve projection effect.

Description

Used to read data from Clickhouse.

Supported DataSource Info

In order to use the Clickhouse connector, the following dependencies are required. They can be downloaded via install-plugin.sh or from the Maven central repository.

Datasource	Supported Versions	Dependency
Clickhouse	universal	Download

Data Type Mapping

Clickhouse Data Type	SeaTunnel Data Type
String / Int128 / UInt128 / Int256 / UInt256 / Point / Ring / Polygon MultiPolygon	STRING
Int8 / UInt8 / Int16 / UInt16 / Int32	INT
UInt64 / Int64 / IntervalYear / IntervalQuarter / IntervalMonth / IntervalWeek / IntervalDay / IntervalHour / IntervalMinute / IntervalSecond	BIGINT
Float64	DOUBLE
Decimal	DECIMAL
Float32	FLOAT
Date	DATE
DateTime	TIME
Array	ARRAY
Map	MAP

Source Options

Name	Type	Required	Default	Description
host	String	Yes	-	ClickHouse cluster address, the format is host:port , allowing multiple hosts to be specified. Such as "host1:8123,host2:8123" .
database	String	Yes	-	The ClickHouse database.
sql	String	Yes	-	The query sql used to search data though Clickhouse server.
username	String	Yes	-	ClickHouse user username.
password	String	Yes	-	ClickHouse user password.
server_time_zone	String	No	ZoneId.systemDefault()	The session time zone in database server. If not set, then ZoneId.systemDefault() is used to determine the server time zone.
common-options		No	-	Source plugin common parameters, please refer to Source Common Options for details.

How to Create a Clickhouse Data Synchronization Jobs

The following example demonstrates how to create a data synchronization job that reads data from Clickhouse and prints it on the local client:

# Set the basic configuration of the task to be performed
env {
  parallelism = 10
  job.mode = "BATCH"
}

# Create a source to connect to Clickhouse
source {
  Clickhouse {
    host = "localhost:8123"
    database = "default"
    sql = "select * from test where age = 20 limit 100"
    username = "xxxxx"
    password = "xxxxx"
    server_time_zone = "UTC"
    result_table_name = "test"
  }
}

# Console printing of the read Clickhouse data
sink {
  Console {
    parallelism = 1
  }
}

Tips

1.SeaTunnel Deployment Document.