UUID V6 Generator

What is UUID version-6 (UUIDv6)

UUID Version 6 (UUIDv6) is a relatively new version of UUID designed to address the sorting and storage efficiency issues of UUID Version 1. UUID Version 6 reorders the bits of UUID Version 1 to allow it to be sorted as an opaque byte sequence. This reordering makes UUIDv6 more efficient in database storage because it improves data locality (DB locality).

Structure and Working Principle of UUID Version 6

UUIDv6 maintains the 128-bit length of UUID but adjusts the storage order of the timestamp. In UUIDv1, the timestamp is divided into low, middle, and high parts, while in UUIDv6, the byte storage order of the timestamp is rearranged so that the storage of the timestamp is from the most significant byte to the least significant byte.

Specifically, UUIDv6 stores the first 48 most significant bits of the 60-bit timestamp value (as specified in UUIDv1) first, followed by the 4-bit version number (in the same position), and then the remaining 12 bits of the original 60-bit timestamp. The clock sequence bits remain unchanged, still following the use and position in RFC 4122.

Application Scenarios for UUID Version 6

UUIDv6 is primarily used in contexts that require improvements over existing UUIDv1, especially in scenarios that focus on database storage efficiency. For systems not involving legacy UUIDv1, it is recommended to use UUIDv7 instead of UUIDv6.

Advantages of UUID Version 6

• Improved Database Locality: The reordering of UUIDv6 helps to enhance the storage efficiency and query performance of data in databases.
• Backward Compatibility: UUIDv6 maintains backward compatibility with UUIDv1, making the migration from UUIDv1 to UUIDv6 relatively easy.
• Applicability: For scenarios that require chronological order but also wish to optimize database storage, UUIDv6 is a good choice.

In summary, UUID Version 6 is designed to solve performance issues in specific scenarios. It improves database storage efficiency by reordering the storage of timestamps while maintaining compatibility with UUID Version 1.