# Messages in Kafka Topic

**URL:** <https://forum.confluent.io/t/messages-in-kafka-topic/4944>\
**Category:** Kafka Connect\
**Created:** [29 April 2022 14:06 UTC](https://forum.confluent.io/t/messages-in-kafka-topic/4944 "2022-04-29T14:06:39Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![cesho](https://avatars.discourse-cdn.com/v4/letter/c/bbce88/32.png) [@cesho](https://forum.confluent.io/u/cesho)\
**Post date:** [29 April 2022 14:06 UTC](https://forum.confluent.io/t/messages-in-kafka-topic/4944/1 "2022-04-29T14:06:39Z")

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Hi,

I had used a JDBC Source connector to fetch data from Netezza Database. I had used the convertor as JsonSchemaConvertor. When viewing the message in Kafdrop, it is showing in different way.

Required format:

```auto
{"name" : "cesho", "age": "XX"}

```

Received format:

```auto
J{"name" : "cesho", "age": "XX"}

```

I want to remove the letter J in front of the parantheses. Kindly help me to sort it out Forum 🙂@rmoff

The config:

```
key.converter: io.confluent.connect.json.JsonSchemaConverter

key.converter.schema.registry.url: http://confluent-schema-registry:8081

value.converter: io.confluent.connect.json.JsonSchemaConverter

value.converter.schema.registry.url: http://confluent-schema-registry:8081

mode: bulk

table.whitelist: ZZ_CEANT_DEMO

topic.prefix: "demo-jdbc-json-"

numeric.mapping: best_fit

poll.interval.ms : 4800000

transforms: "flatten, renameTargetTopic"

transforms.flatten.type: "org.apache.kafka.connect.transforms.Flatten$Value"

transforms.flatten.delimiter: "."

transforms.renameTargetTopic.type: "org.apache.kafka.connect.transforms.RegexRouter"

transforms.renameTargetTopic.regex: "demo-jdbc-json-.*"

transforms.renameTargetTopic.replacement: "demo-jdbc-json"

```

Thanks,  
Cesho

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<div class="post-metadata">

**Author:** ![rmoff](https://sea1.discourse-cdn.com/flex019/user_avatar/forum.confluent.io/rmoff/32/3_2.png) [@rmoff](https://forum.confluent.io/u/rmoff)\
**Post date:** [3 May 2022 09:03 UTC](https://forum.confluent.io/t/messages-in-kafka-topic/4944/2 "2022-05-03T09:03:26Z")

</div>

Is Kafdrop deserialising the JSON Schema correctly? That `J` looks like an ascii representation of the magic byte used by the Schema Registry. See [Formats, Serializers, and Deserializers | Confluent Documentation](https://docs.confluent.io/platform/current/schema-registry/serdes-develop/index.html#wire-format)

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<div class="post-metadata">

**Author:** ![system](https://us1.discourse-cdn.com/flex019/uploads/confluentcommunity/original/1X/c49438c90c9df282e9996fdf6971be890c71b65a.svg) [@system](https://forum.confluent.io/u/system)\
**Post date:** [2 June 2022 09:03 UTC](https://forum.confluent.io/t/messages-in-kafka-topic/4944/3 "2022-06-02T09:03:34Z")

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Closed on 2 June 2022 09:03 UTC

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