I'd be so uncomfortable with this. It sounds like you're placing the full burden of access on a single boundary. I mean, maybe there's more to it that you haven't spoken about here, but "everything rests on this one postgres feature" is an unacceptably unsafe state to me.

Well, I mean it's not only RLS, but yes it's only PostgreSQL doing the access control as far as if they can see a particular table or row.

Every user gets their own role in PG, so the rest of the PG access control system is also used.

We have your normal SSO system(Azure) and if Tootie employee doesn't need access to Asset Control, they don't get any access to the asset schema for instance.

What would be your method?

You would have some app that your dev team runs that handles access control, so your app gets unrestricted access to the DB. Now your app is the single boundary, and it forces everyone to go through your app. How is that better? It also complicates your queries, with a ton of extra where conditions.

A bunch of bespoke access control code you hope is reliable or a feature of the database that's well tested and been around for a long time. pgtap[0] is amazing for ensuring our access control (and the rest of the DB) works.

If some random utility wants to access data, you either have to do something special access wise, or have them also go through your app(let's hope you have an API and it allows for whatever the special is). For us, that random utility gets SQL access just like everyone else. They get RLS applied, etc. They can be naive and assume they have total control, because when they do select * from employees; they get access to only the employee column and rows we want that utility to have.

We have a bunch of tools over the decades that need access to various bits of our data for reason(s). Rather than make them all do wacky stuff with specialized API's, they just get bog standard PG SQL. We don't have to train vendor Tito how to deal with our stuff, we just hand them their auth info to PG and they can go to town. When people want Excel spreadsheets, they just launch excel, do a data query and their data just shows up magically. All from within Excel, using the standard excel data query tools, no SQL needed.

0: https://pgtap.org/

row level security is not a feature specific to Postgres, but more a pretty standard and acceptable way to control access in a multitenant or multicontext environment that pretty much every data provider supports/implements. When it comes to answering a single specific question (like the one RLS targets) I believe you DO want a single, simple answer, vs. something like "it uses these n independent things working in conjunction..."

Conceptually that's no different to any security measures that prevent you from accessing data you're not supposed to? At the end of the day with all data that is colocated you're trusting that some permission feature somewhere is preventing you from accessing data you're not supposed to.

We trust that Amazon or Google or Microsoft are successful in protecting customer data for example. We trust that when you log into your bank account the money you see is yours, and when you deposit it we trust that the money goes into your account. But it's all just mostly logical separation.

It's not like RLS is just some random feature they are misusing. It's specifically for security and is absolutely reliable. Maybe you should do a bit more research before making comments like this.