SECURITY 14 min May 2024
Row-Level Security patterns that actually protect your Supabase data
A comprehensive audit of common RLS mistakes and the patterns that make multi-tenant apps truly secure at the database layer.
Authored by Aevion Studio Engineering Core•Verified Production Pattern
The Pitfall of Client-Side Filtering
Filtering records purely with WHERE clauses in frontend client SDKs creates massive security holes. Database-enforced Row Level Security (RLS) ensures that even if an attacker manipulates API queries, PostgreSQL prevents unauthorized row access.
Optimizing RLS Execution Performance
RLS policies that query foreign tables without indexed foreign keys cause sequential table scans on every request. Wrapping auth.uid() in subqueries and indexing tenant identifier columns ensures near-instant query evaluation.