Getting started with Apache Polaris Catalog in Fivetran's Managed Data Lake Service

Apache Polaris is an open-source catalog for Apache Iceberg tables, offering a standardized REST interface to manage metadata, which enables query engines to access tables without embedding technology-specific code. Fivetran employs Polaris in its Managed Data Lake Service, utilizing it as the default catalog for Iceberg tables, with support for destinations like Amazon S3 and Google Cloud Storage. The service ensures data integrity by allowing only Fivetran to modify catalog metadata, while users are advised to query tables through the catalog rather than directly accessing raw Parquet files to avoid issues like file discovery overhead and lack of ACID guarantees. Polaris offers benefits such as snapshot isolation, transactional consistency, and seamless schema evolution, which are crucial for maintaining data integrity and performance. Various query engines, including Apache Spark, Snowflake, and Trino, are compatible with Polaris, with OAuth2 authentication facilitating secure access. As Polaris evolves, it is expected to graduate from the Apache Incubator by late 2025, with improvements in DuckDB and Snowflake support anticipated.