Apache Flink CDC vs Google Cloud Datastream

Apache Flink CDC is a distributed data integration tool for real-time and batch workloads, built on Apache Flink. It supports full database and sharded-table synchronization, schema evolution and data transformation. With its YAML Pipeline API, users can declare sources, sinks, routing, transformations and schema evolution rules. SQL and DataStream APIs are also available for defining CDC sources and custom Flink streaming applications. Listed pipeline connectors include Doris, Elasticsearch, Fluss, Hudi, Iceberg, Kafka, MaxCompute, MySQL, OceanBase, Oracle, Paimon, PostgreSQL and StarRocks. SQL and DataStream source connectors also include SQL Server, MongoDB, TiDB, Db2 and Vitess. Flink CDC 3.6 is listed as compatible with Flink 1.20 and 2.2; version 3.6.0 requires JDK 11 or later. Deployment is self-hosted: download and extract Flink CDC and connector JARs, then run them with an Apache Flink deployment. It is free under the Apache 2.0 License and lists Linux, macOS, Windows and self-hosted environments as platforms.

Google Cloud Datastream is a serverless change data capture and replication service for synchronizing data. Streams can capture ongoing updates and backfill historical records, while the service scales automatically without resources for users to provision or manage. Supported destinations include BigQuery, Cloud Storage, and Apache Iceberg tables. Documented sources include Oracle, MySQL, PostgreSQL, AlloyDB, SQL Server, MongoDB, Spanner, Salesforce, ServiceNow, Workday, and Microsoft Dataverse; some sources are marked as preview. Datastream can work with Dataflow templates to load data from Cloud Storage into destinations including BigQuery, Cloud SQL, and Spanner. Connectivity options include IP allowlisting, a forward SSH tunnel, and private connectivity over VPC peering. Processing is charged, idle streams incur no cost, and other Google Cloud resources are billed separately. The free tier includes 100 GiB of eligible CDC data per month per billing account. Events are delivered at least once, but ordering is not guaranteed. Datastream is administered through the Google Cloud console, CLI, or REST API.