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Hello, How can I prevent an user from inserting multiple rows in a table ?

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Hi <:vmathi:937589524299677739> you can use policies to restrict the access depending on conditions  <@768660426912301067>

Do you have an example policy that lets only insert one row ?

I searched but can't find something that would do that

You can simply check if ``auth.user().uuid`` is already in the table. Unfortunately, I'm not really good at Postgres, so i can't drop you a real world example 😅

Is an insert policy working row by row even when an INSERT inserts multiple row ? that would be great but i'm not so sure

Btw yea, Supabase has a very good JS SDK documentation, but documentation about PostgreSQL possibilities, like triggers etc, is pretty lacking, it needs much more documentation to show us how to do specific things with Postgre, since Postgre's documentation itself isn't very clear

Actually there is no docs about that because there are already a docs, and the official Postgres docs isn't that bad

They don't provide example on specific case, so it's hard to understand exactly what to do securely

Since it's a security concern, I think it's important to document it as much as possible

What do you mean by “prevent a user from inserting multiple rows in a table” 
Like do you mean like, just ONE row per table per user? 
Or do you mean, prevent multiple rows from being inserted per statement/transaction?

- also the Postgres docs are REALLY thorough, but it takes time to understand it. Backend docs like PostgreSQL are a lot more technical and is a learning curve to understand than like say front end docs (like react)