On 2020-Oct-15, Dirk Krautschick wrote: > Hi, > > I have here a situation with the usage of UUID. Here the database user > allows UUIDs with less then 16 byte lengths (please don't ask :-) ). > > Of course there are some technical ways to do the filling of the not > used bytes but I hope there is a better solution. This UUID is used as > primary Key and for indexing. How much shorter than 16 bytes are you expecting your UUIDs to be? If they're not short enough, you'll still have to store a lot of padding space, and considering that you'll need a length indicator if you use variable length, it does not really sound like you'll save much actual space. And you'll definitely be getting a slower datatype, since doing operations will become more complex. If this were me, I would see about zeroing out the unused bytes and not waste a lot of developer time on this.
