PostgreSQL and Kafka Connect integration issue - postgresql

Question

I am testing JDBC Sink connector to dump records from Kafka to PostgreSQL. Here is the Connector config:
{
"name": "jdbc-sink-postgresql-1",
"config": {
"connector.class": "io.confluent.connect.jdbc.JdbcSinkConnector",
"tasks.max": "1",
"topics": "role",
"connection.url": "jdbc:postgresql://localhost:5432/postgres?user=&password=",
"auto.create": "false",
"insert.mode": "upsert",
"mode":"incrementing",
"table.name.format":"role",
"pk.mode":"record_value",
"pk.fields":"role_id"
}
}
When I run the connector, I am getting below exception:
java.sql.BatchUpdateException: Batch entry 1 INSERT INTO "role" ("role_id","role_name") VALUES (123,'admin') ON CONFLICT ("role_id") DO UPDATE SET "role_name"=EXCLUDED."role_name" was aborted.
Call getNextException to see the cause.
at org.postgresql.jdbc2.AbstractJdbc2Statement$BatchResultHandler.handleError(AbstractJdbc2Statement.java:2778))
Any pointers as to what am I missing here? Please let me know if more information is needed.

Answer 1

So, the problem was with the table. This is how I created table at first:
CREATE TABLE role(
role_id int PRIMARY KEY,
role_name VARCHAR (255) UNIQUE NOT NULL
);
The test data in topic looked like this:
./bin/kafka-avro-console-producer --broker-list localhost:9092 --topic role --property schema.registry.url=http://localhost:8081/ --property value.schema='{"type":"record","name":"myRecord","fields": [{"name": "role_id","type": "int"},{"name": "role_name","type": "string"}]}' --key-serializer org.apache.kafka.common.serialization.StringSerializer --value-serializer io.confluent.kafka.serializers.KafkaAvroSerializer --property print.key=true
{"role_id":122, "role_name":"admin"}
{"role_id":123, "role_name":"admin"}
{"role_id":124, "role_name":"admin"}
{"role_id":125, "role_name":"admin"}
{"role_id":126, "role_name":"admin"}
So, when my test data had the same value for role_name field again and again, it violated the unique constraint and hence the error.
What all I did?
I dropped the table.
Created a new table without the unique key constraint and the above data was pushed to PostgreSQL without issues.