> Pretty much all of the things you'd want in a relational database are now present in Mongodb too.
On the "relational" front, it has denormalized-only schema validation and limits transactions to replica sets (so no transactions with sharding), while also recommending single-document transactions over multi-document transaction via denormalization. (FWIW, transactions aren't available in any open source release).
On the "database" front, it has a history of misleading users and remorselessly dropping data.
> Postgres will get you pretty far
Postgres is an actual relational database, open source, battle-proven with a good design and a great team behind it. It never claimed to be good at, let alone capable of, doing things it could not actually do (well, or at all).
> but beyond a certain point the scaling story breaks down and you have to hack some sort of user space sharding solution.
Scaling IS a hard thing, and presents itself quite differently to different use-cases. Nevertheless, horizontally scaling Postgres — for when one truly hits the petabyte-scale — is a problem that has been solved correctly many times before (out of core). For a similar-to-MongoDB method, check out Citus, with the assurance that it only adds to an actual database; as opposed to the MongoDB way of doing things: make up and promise magic scaling solutions that "Just Work", then try to build a database on top of it.
On the "relational" front, it has denormalized-only schema validation and limits transactions to replica sets (so no transactions with sharding), while also recommending single-document transactions over multi-document transaction via denormalization. (FWIW, transactions aren't available in any open source release).
On the "database" front, it has a history of misleading users and remorselessly dropping data.
> Postgres will get you pretty far
Postgres is an actual relational database, open source, battle-proven with a good design and a great team behind it. It never claimed to be good at, let alone capable of, doing things it could not actually do (well, or at all).
> but beyond a certain point the scaling story breaks down and you have to hack some sort of user space sharding solution.
Scaling IS a hard thing, and presents itself quite differently to different use-cases. Nevertheless, horizontally scaling Postgres — for when one truly hits the petabyte-scale — is a problem that has been solved correctly many times before (out of core). For a similar-to-MongoDB method, check out Citus, with the assurance that it only adds to an actual database; as opposed to the MongoDB way of doing things: make up and promise magic scaling solutions that "Just Work", then try to build a database on top of it.