Add Avro and AvroConfluent Input/Output Formats

Why it matters

This feature enables ClickHouse to read and write data using the Avro serialization format, including the Confluent Schema Registry integration. It addresses the need for native compatibility with Avro-encoded data commonly used in data streaming and big data ecosystems, facilitating easier ingestion and export of Avro data.

How to use it

Use Avro or AvroConfluent as the format specifier in your INSERT, SELECT, or FORMAT clauses. For example, to read Avro data:

SELECT * FROM table FORMAT Avro;

To write data in Avro format with Confluent Schema Registry integration, specify AvroConfluent and provide required schema configuration options as needed.