"new row violates row-level security policy" in Supabase

What it means

Row Level Security (RLS) is switched on for the table, which is good. But no policy says this user is allowed to insert this row, so Supabase blocks it.

Why AI tools cause it

AI tools often turn RLS on (or you did, after a security warning) without writing the matching policies. Or the insert doesn't include the user_id the policy checks for.

The fix

1. In Supabase, open Authentication → Policies and find the table.
2. Add an INSERT policy that lets signed-in users add rows they own, for example with check (auth.uid() = user_id).
3. Make sure your insert sends the user's id in the user_id column, and that the user is actually signed in when it runs.

Don't fix this by turning RLS off. That makes the table readable and writable by anyone with your public key.

Paste this into your AI

Inserting into my Supabase table fails with "new row violates row-level security policy". Show me the RLS policies this table needs so users can create, read, update and delete only their own rows, as SQL I can run, and check my insert code sends user_id from the signed-in session.

Still broken?

If it fails on a server route, check whether that code is using a signed-in client or an anonymous one. An anonymous client has no auth.uid().