Delta Lake

Delta Lake is an open-source storage framework and table format that adds a transaction log over Parquet files on object storage. It provides ACID transactions, schema enforcement and evolution, time travel, and efficient upserts and deletes.

It originated at Databricks and has its deepest integration with Apache Spark, where it is the default table format; connectors and standalone readers extend access to Trino, Flink, and other engines.

Delta Lake anchors lakehouse architectures particularly in Spark- and Databricks-centric environments. It is most often weighed against Apache Iceberg, with ecosystem alignment usually the deciding factor.