DB2

JDBC DB2 Sink Connector

Description​

Write data through jdbc. Support Batch mode and Streaming mode, support concurrent writing, support exactly-once semantics (using XA transaction guarantee).

Key Features​

• exactly-once

• cdc

Use Xa transactions to ensure exactly-once. So only support exactly-once for the database which is support Xa transactions. You can set is_exactly_once=true to enable it.

Data Type Mapping​

DB2 Data Type	Nexus Data Type
BOOLEAN	BOOLEAN
SMALLINT	SHORT
INT INTEGER	INTEGER
BIGINT	LONG
DECIMAL DEC NUMERIC NUM	DECIMAL(38,18)
REAL	FLOAT
FLOAT DOUBLE DOUBLE PRECISION DECFLOAT	DOUBLE
CHAR VARCHAR LONG VARCHAR CLOB GRAPHIC VARGRAPHIC LONG VARGRAPHIC DBCLOB	STRING
BLOB	BYTES
DATE	DATE
TIME	TIME
TIMESTAMP	TIMESTAMP
ROWID XML	Not supported yet

Sink Options​

Name	Type	Required	Default	Description
url	String	Yes	-	The URL of the JDBC connection. Refer to a case: jdbc:db2://127.0.0.1:50000/dbname
driver	String	Yes	-	The jdbc class name used to connect to the remote data source, if you use DB2 the value is com.ibm.db2.jdbc.app.DB2Driver.
user	String	No	-	Connection instance user name
password	String	No	-	Connection instance password
query	String	No	-	Use this sql write upstream input datas to database. e.g INSERT ...,query have the higher priority
database	String	No	-	Use this database and table-name auto-generate sql and receive upstream input datas write to database. This option is mutually exclusive with query and has a higher priority.
table	String	No	-	Use database and this table-name auto-generate sql and receive upstream input datas write to database. This option is mutually exclusive with query and has a higher priority.
primary_keys	Array	No	-	This option is used to support operations such as insert, delete, and update when automatically generate sql.
support_upsert_by_query_primary_key_exist	Boolean	No	false	Choose to use INSERT sql, UPDATE sql to process update events(INSERT, UPDATE_AFTER) based on query primary key exists. This configuration is only used when database unsupport upsert syntax. Note: that this method has low performance
connection_check_timeout_sec	Int	No	30	The time in seconds to wait for the database operation used to validate the connection to complete.
max_retries	Int	No	0	The number of retries to submit failed (executeBatch)
batch_size	Int	No	1000	For batch writing, when the number of buffered records reaches the number of batch_size or the time reaches checkpoint.interval , the data will be flushed into the database
is_exactly_once	Boolean	No	false	Whether to enable exactly-once semantics, which will use Xa transactions. If on, you need to set xa_data_source_class_name.
generate_sink_sql	Boolean	No	false	Generate sql statements based on the database table you want to write to
xa_data_source_class_name	String	No	-	The xa data source class name of the database Driver, for example, DB2 is com.db2.cj.jdbc.Db2XADataSource, and please refer to appendix for other data sources
max_commit_attempts	Int	No	3	The number of retries for transaction commit failures
transaction_timeout_sec	Int	No	-1	The timeout after the transaction is opened, the default is -1 (never timeout). Note that setting the timeout may affect exactly-once semantics
auto_commit	Boolean	No	true	Automatic transaction commit is enabled by default
properties	Map	No	-	Additional connection configuration parameters,when properties and URL have the same parameters, the priority is determined by the specific implementation of the driver. For example, in MySQL, properties take precedence over the URL.
common-options		no	-	Sink plugin common parameters, please refer to Sink Common Options for details

Tips​

If partition_column is not set, it will run in single concurrency, and if partition_column is set, it will be executed in parallel according to the concurrency of tasks.

Task Example​

Simple:​

This example defines a Nexus synchronization task that automatically generates data through FakeSource and sends it to JDBC Sink. FakeSource generates a total of 16 rows of data (row.num=16), with each row having two fields, name (string type) and age (int type). The final target table is test_table will also be 16 rows of data in the table. Before run this job, you need create database test and table test_table in your DB2.

# Defining the runtime environment
env {
  parallelism = 1
  job.mode = "BATCH"
}

source {
  # This is a example source plugin **only for test and demonstrate the feature source plugin**
  FakeSource {
    parallelism = 1
    result_table_name = "fake"
    row.num = 16
    schema = {
      fields {
        name = "string"
        age = "int"
      }
    }
  }
  # If you would like to get more information about how to configure Nexus and see full list of source plugins,
  # please go to https://nexus.apache.org/docs/category/source-v2
}

transform {
  # If you would like to get more information about how to configure Nexus and see full list of transform plugins,
    # please go to https://nexus.apache.org/docs/category/transform-v2
}

sink {
    jdbc {
        url = "jdbc:db2://127.0.0.1:50000/dbname"
        driver = "com.ibm.db2.jdbc.app.DB2Driver"
        user = "root"
        password = "123456"
        query = "insert into test_table(name,age) values(?,?)"
        }
  # If you would like to get more information about how to configure Nexus and see full list of sink plugins,
  # please go to sink page
}

Generate Sink SQL​

This example not need to write complex sql statements, you can configure the database name table name to automatically generate add statements for you

sink {
    jdbc {
        url = "jdbc:db2://127.0.0.1:50000/dbname"
        driver = "com.ibm.db2.jdbc.app.DB2Driver"
        user = "root"
        password = "123456"
        # Automatically generate sql statements based on database table names
        generate_sink_sql = true
        database = test
        table = test_table
    }
}

Exactly-once :​

For accurate write scene we guarantee accurate once

sink {
    jdbc {
        url = "jdbc:db2://127.0.0.1:50000/dbname"
        driver = "com.ibm.db2.jdbc.app.DB2Driver"
    
        max_retries = 0
        user = "root"
        password = "123456"
        query = "insert into test_table(name,age) values(?,?)"
    
        is_exactly_once = "true"
    
        xa_data_source_class_name = "com.db2.cj.jdbc.Db2XADataSource"
    }
}