How can data from Greenplum and Trino be transferred to ClickHouse?

There are several approaches to transfer data from Greenplum and Trino to ClickHouse:

1. Export and import via files

   • Export data from Greenplum/Trino to CSV or Parquet.
   • Load files into ClickHouse using clickhouse-client or clickhouse-copier.

2. Using connectors and ETL tools

   • Use Apache Airflow, NiFi, or other ETL systems to organize data flows.
   • Configure connectors to read from Greenplum/Trino and write to ClickHouse.

3. Direct connection via JDBC/ODBC

   • Trino supports connecting to various sources; you can set up queries that export data directly.
   • ClickHouse supports JDBC/ODBC; scripts can be written for migration.

4. Using Kafka as an intermediate layer

   • Send data from Greenplum/Trino to Kafka.
   • Subscribe to Kafka from ClickHouse via Kafka Engine.

The choice depends on data volume, speed and update frequency requirements, as well as infrastructure.