Hi everyone, The discussion on FLIP-604 [1] has been open for two weeks now. Thanks to Timo, Mate, and Gustavo for the feedback. All the points raised have been addressed and folded into the FLIP. The thread has settled and I don't see any open items.
Given the consensus, I'll start a VOTE thread shortly. Thanks again, Ramin [1] https://cwiki.apache.org/confluence/spaces/FLINK/pages/446070993/FLIP-604+Complete+VARIANT+Primitive+Coverage+with+UUID+and+Timestamps On Tue, Aug 4, 2026 at 12:28 PM Ramin Gharib <[email protected]> wrote: > Hi everyone, > > I'd like to start a discussion on FLIP-604: Complete VARIANT > Primitive Coverage with UUID and Timestamps. [1] > > FLIP-521 [2] shipped VARIANT in Flink 2.1, but it only implements Parquet > Variant primitive codes 0 through 16. The open Variant spec goes > through 20: TIME, nanosecond timestamps, and UUID. So a VARIANT > written by Spark, Iceberg, or any Parquet writer that holds one of > these values cannot be read by Flink today, which breaks the > lakehouse round-trip VARIANT was meant to support. > > This FLIP completes the primitive set. TIME and the nanosecond > timestamps reuse types Flink already has. UUID needs a type to land > on, so the FLIP also adds a native 16-byte UUID type as a first-class > SQL type, with casts, ordering, a UUID literal, and UUID_V4 and > UUID_V7 generator functions. > > One point worth noting: no Calcite upgrade is required. Calcite has > had a UUID type since 1.39, the same release FLIP-521 adopted for > VARIANT, and Flink already runs Calcite 1.41. The 16-byte layout also > matches every engine with a native UUID type, including PostgreSQL, > Trino, DuckDB, ClickHouse, Snowflake, and Iceberg. > > Looking forward to your feedback. > > Best, > Ramin Gharib > > [1] > https://cwiki.apache.org/confluence/spaces/FLINK/pages/446070993/FLIP-604+Complete+VARIANT+Primitive+Coverage+with+UUID+and+Timestamps > [2] > https://cwiki.apache.org/confluence/spaces/FLINK/pages/349637099/FLIP-521+Integrating+Variant+Type+into+Flink+Enabling+Efficient+Semi-Structured+Data+Processing > >
