Data Engineering *

In late September 2025, PostgreSQL 18 was released. It received the long-awaited built-in function uuidv7(). The uuidv7() function generates UUID version 7 (UUIDv7) identifiers of the binary data type uuid in accordance with the international standard RFC 9562. These identifiers are recommended for use as primary keys. If necessary, the timestamp with the time zone can be extracted from them using the uuid_extract_timestamp() function.

UUIDv7 combines the global uniqueness of primary keys, a negligibly low probability of collisions (unacceptable random matches), and ordering by the generation timestamp. This is achieved without using centralized coordination or MAC addresses. The risk of collisions is no higher than with the previously most popular (random) UUID version 4 type.

Due to ordering by generation timestamp, UUIDv7 results in significantly higher performance and smaller index sizes compared to UUIDv4. The most significant bits of UUIDv7 identifiers can be used as a partition key.

UUIDv7 provides the same performance for CRUD database operations as when using auto-increment (the serial type and its modern equivalent GENERATED ... AS IDENTITY). The time to generate a UUIDv7 identifier is approximately a thousand times less than the record insertion time, so the UUIDv7 generation rate does not affect database performance.

Using UUIDv7 eliminates the fundamental drawbacks of auto-increment: