Hacker News Reader

Comment by henryfjordan | Hacker News Reader

How exactly is EdgeDB run? Is it a separate process from Postgres, or some kind of plugin? Can I run it over an existing Postgres instance?

If I build a DB Schema in EdgeDB, can I interact with the underlying Postgres instance using regular SQL?

View on HN

It runs as a separate (stateless) process between the client and the PostgreSQL server. There was a talk about the details of the architecture on the live stream today: https://youtu.be/WRZ3o-NsU_4?t=5294

This sounds very similar to Hasura, which compiles graphQL down to SQL. Have you considered adding the subscription feature like they have?

It's something we want to do at some point, but unlike Hasura, which operates on GraphQL which is conceptually much simpler and limited, EdgeQL would be much harder to fit onto a "pipelined polling" model that Hasura utilizes to implement subs.

So, there is, basically, no way to work with Postgres directly, as well as installing EdgeDB with the use of the existing Postgres installation and its data, right? Feels like a Postgres is a prisoner of the EdgeDB :)

If you look at the code they used to have —postgres-dsn URL, now they changed it to —backend-dsn. If you go beyond the marketing, edgedb is a postgres connection pool+orm combined together with a query language (its a huge work in itself and commendable given it takes away many dependencies and provide a consistent developer experience). It’s leveraging postgresql server which is the true database providing ACID compliance.

Edgedb is more akin to hasura than to a database in traditional sense.

Hi there! Yes, I do understand and that the EdgeDB is "a postgres connection pool+orm combined together" and the work guys did is incredible. And I do beleive it will find its niche. But for me, personaly, the idea of "postgres is now a black box for you, don't even try to go deeper into it" stops me from digging into EdgeDB right away (the tooling is amazing! migrations!) and even trying it in our production for our enterprize clients. Probably, with time, when edgeql can fully replace sql and plpgsql, we could say that EdgeDB is ready for everything. BTW, @RedCrowbar, how can I call a udf or procedure (written in sql/plpgsql) from edgeql? I didn't find it in the docs.

There is no way to call UDF SQL (or PL/pgSQL) functions from EdgeDB, because there is no way to _define_ or manage them. The only place that is allowed to do this is the standard library (and, in the near future, extensions).

We realize that the database must be extensible and flexible, so non-EdgeQL UDF will become a reality (and if things work out the way we hope they will, they'll be amazing and far beyond what you can do with plpgsql).

Reply on news.ycombinator.com