Vertica Sink Connector for Confluent Platform

You can use the Kafka Connect Vertica Sink connector to export data from Apache Kafka® topics to Vertica. The Vertica Sink connector periodically polls records from Kafka and adds them to a Vertica table.

Important

The Vertica Sink connector is only compatible with Vertica 9.0.1 and later, and does not support update functionality at this time.

Features

The Vertica Sink connector includes the following features:

At least once delivery

This connector guarantees that records from the Kafka topic are delivered at least once.

Dead Letter Queue

This connector supports the Dead Letter Queue (DLQ) functionality. For information about accessing and using the DLQ, see Confluent Platform Dead Letter Queue.

Multiple tasks

The Vertica Sink connector supports running one or more tasks. You can specify the number of tasks in the tasks.max configuration parameter. This can lead to performance gains when multiple files need to be parsed.

Auto-creation and auto-evoluton

Tip

Ensure the Vertica user has the appropriate permissions for DDL. For more information see Database Users and Privileges.

If auto.create is enabled, the connector can create the destination table if it is found to be missing. The creation takes place online with records being consumed from the topic, since the connector uses the record schema as a basis for the table definition. The connector creates a table without adding a primary key or primary key constraints. However, if auto.create is disabled and a table is not present in the database, then the connector task fails with an error stating that auto.create is disabled.

If auto.evolve is enabled, the connector can perform limited auto-evolution by issuing ALTER on the destination table when it encounters a record for which a column is found to be missing. If auto.evolve is disabled then no evolution is performed and the connector task fails with a “missing columns” error. Because data type changes and removal of columns can be dangerous, the connector does not attempt to perform such evolutions on the table. Also, the connector does not attempt to add primary key constraints.

For both auto-creation and auto-evolution, if the corresponding field for the column in the schema is optional, then there must be a default value in the schema (not null).

Important

For backward-compatible table schema evolution, missing fields in a record must have a default value in the table. If no default value is found in the table for the particular missing field, the record is rejected. The connector rejects records which have null value fields.

Schema Type Vertica
INT8 INT
INT16 INT
INT32 INT
INT64 INT
FLOAT32 FLOAT
FLOAT64 FLOAT
BOOLEAN BOOLEAN
STRING VARCHAR(1024)
BYTES VARBINARY(1024)
Decimal DECIMAL
Date DATE
Time TIME
Timestamp TIMESTAMP

Install the Vertica connector

You can install this connector by using the confluent connect plugin install command, or by manually downloading the ZIP file.

Prerequisites

  • Kafka Broker: Confluent Platform 3.3.0 or later, or Kafka 0.11.0 or later.

  • Connect: Confluent Platform 4.0.0 or later, or Kafka 1.0.0 or later.

  • Java 8+. Note that Java 8 is deprecated in versions 7.2 and later of Confluent Platform. For more details, view Java compatibility with Confluent Platform by version.

  • You must install the connector on every machine where Connect will run.

  • Install the latest (latest) connector version.

  • Download and install the vertica-jdbc.jar and place it in the connector’s /lib folder as shown in the following example:

    <path-to-connector>/confluentinc-kafka-connect-vertica-1.2.2/lib/vertica-jdbc-9.2.1-0.jar
    
  • Install the Confluent Hub Client. This is installed by default with Confluent Enterprise.

Install the connector using the Confluent CLI

To install the latest connector version, navigate to your Confluent Platform installation directory and run the following command:

confluent connect plugin install confluentinc/kafka-connect-vertica:latest

You can install a specific version by replacing latest with a version number as shown in the following example:

confluent connect plugin install confluentinc/kafka-connect-vertica:1.3.0

Install the connector manually

Download and extract the ZIP file for your connector and then follow the manual connector installation instructions.

License

You can use this connector for a 30-day trial period without a license key.

After 30 days, you must purchase a connector subscription which includes Confluent enterprise license keys to subscribers, along with enterprise-level support for Confluent Platform and your connectors. If you are a subscriber, you can contact Confluent Support at support@confluent.io for more information.

For license properties, see Confluent Platform license and for information about the license topic, see License topic configuration.

Configuration properties

For a complete list of configuration properties for this connector, see Configuration Reference for Vertica Sink Connector for Confluent Platform.

For an example of how to get Kafka Connect connected to Confluent Cloud, see Connect Self-Managed Kafka Connect to Confluent Cloud.

Quick start

In this quick start, the Vertica connector exports data produced by the Avro console producer to a Vertica database.

Before you begin, start the Vertica database and manually create a table using the same name as the Kafka topic. Use the same schema that is used for the data in the Kafka topic or add auto.create=true.

Set up Vertica

To manually set up Vertica, complete the following steps:

  1. Pull the Vertica image from Docker Registry and run it with a persistent datastore.

    docker pull dataplatform/docker-vertica
    docker run -p 5433:5433 -d -v /data/vertica/vertica_data:/home/dbadmin/docker dataplatform/docker-vertica
    
  2. Get the Docker image ID and launch a bash shell within the container.

    docker ps
    docker exec -it <image_id> bash
    
  3. Launch the Vertica console.

    cd /opt/vertica/bin
    ./vsql -hlocalhost -Udbadmin
    
  4. Create a table and insert data.

    create table mytable(f1 varchar(20));
    

Start Confluent services

Use the following steps to start Confluent services.

  1. Start the services using the Confluent CLI.

    confluent local services start
    

    Every service starts in order, printing a message with its status.

    Starting Zookeeper
    Zookeeper is [UP]
    Starting Kafka
    Kafka is [UP]
    Starting Schema Registry
    Schema Registry is [UP]
    Starting Kafka REST
    Kafka REST is [UP]
    Starting Connect
    Connect is [UP]
    Starting KSQL Server
    KSQL Server is [UP]
    Starting Control Center
    Control Center is [UP]
    
  2. Import a few records with a simple schema in Kafka by starting the Avro console producer as follows:

      ./bin/kafka-avro-console-producer --broker-list localhost:9092 --topic mytable \
    --property value.schema='{"type":"record","name":"myrecord","fields":[{"name":"f1","type":"string"}]}'
    
  3. In the console producer, enter the following:

    {"f1": "value1"}
    {"f1": "value2"}
    {"f1": "value3"}
    

    The three records entered are published to the Kafka topic mytable in Avro format.

Property-based example

Create a configuration file for the connector. This file is included with the connector in etc/kafka-connect-vertica/vertica-sink-connector.properties. This configuration is used typically along with standalone workers.

name=VerticaSinkConnector
tasks.max=1
topics=mytable
connector.class=io.confluent.vertica.VerticaSinkConnector
vertica.database=docker
vertica.host=127.0.0.1
vertica.port=5433
vertica.username=dbadmin
vertica.password=<password>
auto.create=true
confluent.topic.bootstrap.servers=localhost:9092
confluent.topic.replication.factor=1

Start the Vertica connector by loading its configuration with the following command:

confluent local services connect connector load VerticaSinkConnector --config vertica-sink-connector.properties
{
  "name" : "VerticaSinkConnector",
  "config" : {
     "tasks.max":"1",
     "topics":"mytable",
     "connector.class":"io.confluent.vertica.VerticaSinkConnector",
     "vertica.database":"docker",
     "vertica.host":"127.0.0.1",
     "vertica.port":"5433",
     "vertica.username":"dbadmin",
     "vertica.password":"",
     "auto.create":"true",
     "confluent.topic.bootstrap.servers":"localhost:9092",
     "confluent.topic.replication.factor":"1"
     },
  "tasks": []
}

REST-based example

Use this setting with distributed workers.

  1. Write the following JSON to config.json and configure all of the required values.

    {
      "name" : "VerticaSinkConnector",
      "config" : {
        "tasks.max":"1",
        "topics":"mytable",
        "connector.class":"io.confluent.vertica.VerticaSinkConnector",
        "vertica.database":"docker",
        "vertica.host":"127.0.0.1",
        "vertica.port":"5433",
        "vertica.username":"dbadmin",
        "vertica.password":"",
        "confluent.topic.bootstrap.servers":"localhost:9092",
        "confluent.topic.replication.factor":"1"
      },
      "tasks": []
    }
    
  2. Use curl to post the configuration to one of the Connect workers. Change http://localhost:8083/ the endpoint of one of your Connect workers. For more information about the REST APT, see REST API.

    curl -sS -X POST -H 'Content-Type: application/json' --data @config.json http://localhost:8083/connectors
    
  3. Use the following command to update the configuration of existing connector:

    curl -s -X PUT -H 'Content-Type: application/json' --data @config.json http://localhost:8083/connectors/VerticaSinkConnector/config
    
  4. Verify the connector started successfully and review the Connect worker’s log with the following command:

    confluent local services connect log
    

    At the end of the log you should see that the connector starts, logs a few messages, and then adds data from Kafka to the Vertica table.

  5. Once the connector has ingested records, check whether the data is available in the Vertica table by running the following command in the Vertica console:

    select * from mytable;
        f1
      --------
      value1
      value2
      value3
      (3 rows)
    
  6. Stop the Connect worker and all other Confluent services.

    confluent local stop
    

    Your output should resemble the following:

    Stopping Control Center
    Control Center is [DOWN]
    Stopping KSQL Server
    KSQL Server is [DOWN]
    Stopping Connect
    Connect is [DOWN]
    Stopping Kafka REST
    Kafka REST is [DOWN]
    Stopping Schema Registry
    Schema Registry is [DOWN]
    Stopping Kafka
    Kafka is [DOWN]
    Stopping Zookeeper
    Zookeeper is [DOWN]
    
  7. Stop all services and remove any data generated during this quick start by entering the following command:

    confluent local destroy
    

    Your output should resemble the following:

    Stopping Control Center
    Control Center is [DOWN]
    Stopping KSQL Server
    KSQL Server is [DOWN]
    Stopping Connect
    Connect is [DOWN]
    Stopping Kafka REST
    Kafka REST is [DOWN]
    Stopping Schema Registry
    Schema Registry is [DOWN]
    Stopping Kafka
    Kafka is [DOWN]
    Stopping Zookeeper
    Zookeeper is [DOWN]
    Deleting: /var/folders/ty/rqbqmjv54rg_v10ykmrgd1_80000gp/T/confluent.PkQpsKfE