[montanalow]

Full disclaimer, I work on PostgresML, and I'm not a MindsDB expert.

They both do ML in the database, but we've been at least as focused on scalability for Postgres workloads as ML functionality, with our PgCat project. It's a pooler that gives us load balancing, sharding, failover etc to handle large clusters of many machines for application and inference workloads to scale horizontally.

OTOH MindsDB interconnects with just about every data source out there, which you may consider an advantage.