Since there is some UUID hate here, some missing pros to using them: - No round trip for generating keys, data can be sent in with an existing or new uuid with

Since there is some UUID hate here, some missing pros to using them: - No round trip for generating keys, data can be sent in with an existing or new uuid without having to hit the autonumber/keymaster, removes a single point of failure for a small fee on each row. Storage is cheap so 16-byte uuid is not a deal-breaker, the benefit is speed and horizontal scalability. Optimized read-only tables and/or caching can be made where this has any impact at all. - Some databases like Oracle you need a sequence to even do autoumbering, huge pain - Autonumbering is a pain when having to replicate across environments or when you start getting multiple databases and clusters - Numeric ids for important data is not exposed, prevents easily incrementing for next/previous (other ways to do this but this is one) - Many databases have a UUID field or field optimized for unique ids/guids/uuids now - If you were a piece of data wouldn't you want to be unique? All your data are unique snowflakes with UUIDs. On a serious note, this can help to identify data across all types and not just in the same table.