sequential-uuids VS Pomelo.EntityFrameworkCore.MySql

Disclaimer: not a dba so my terms might not be appropriate

I’ve seen uuid4 which replaces the first 4 bytes with a timestamp. It was mentioned to me that this strategy allows postgres to write at the end of the index instead of arbitrarily on disk. I also presume it means it has some decent sorting.

[inspiration](https://github.com/tvondra/sequential-uuids/blob/master/sequ...)

yum install -y git git clone https://github.com/tvondra/sequential-uuids.git ysqlsh -h $(hostname) --echo-all --quiet \ --file sequential-uuids/test/sql/uuids.sql | sdiff sequential-uuids/test/expected/uuids.out -

If you want to keep locality when using uuids, use a different generation function such as: https://github.com/tvondra/sequential-uuids

OP, have a pretty large B2B SAAS app with all UUID pkeys, and the largest issues i'd say with UUID compared to bigint are: size, index bloat, WAL bloat, much slower GIST indexes (for exclusion constraints). You can work around some of the issues (WAL bloat, index bloat) by using a better behaved UUID generation function: https://github.com/tvondra/sequential-uuids You can get something similar for your app side of things if you need to generate UUIDs there.

Use this: https://github.com/tvondra/sequential-uuids

If you cannot install extensions, I just wrote a PL/PGSQL implementation for the time-based generator I could share.

Just fyi, UUID in Postgres is not 40 text chars, it's 16 bytes binary and has a canonical text representation. Also, you don't need to use UUIDv4, I am quite partial to: https://github.com/tvondra/sequential-uuids

EntityFramework uses providers to translate Linq queries into real queries and connect to the datasource and convert the data into .net readable format. The MySQL provider for .NET is the official one but I think it has fallen on hard times and is not developed as much as before. You should probably look at Pomelo, which is a community library for .net core: https://github.com/PomeloFoundation/Pomelo.EntityFrameworkCore.MySql

For MySQL and friends you'll need the Pomelo data provider from https://github.com/PomeloFoundation/Pomelo.EntityFrameworkCore.MySql . Turns out there's an example of using the MySQL provider about halfway down that shows how to, but it is missing the '-o Model' parameter that you'd use to get your database model into a folder called Model.

This approach has become my preferred way of generating IDs for database rows. It is relatively space efficient and doesn't require a round trip to the database to generate an ID like auto increment does.

While working on a C# implementation for MySQL and we found that when the DB uses Little Endian Binary that the GUID must be reversed to store in order:

https://github.com/PomeloFoundation/Pomelo.EntityFrameworkCo...