The RLS Silent Trap: Why Supabase Queries Return Empty Without Error

Row Level Security is PostgreSQL's deny-by-default authorization mechanism, and it's a leading cause of silent production bugs in Supabase applications. When RLS is enabled but policies aren't properly configured, queries return empty results with no error message—making the root cause nearly invisible during debugging. Understanding how to write scoped SELECT policies is essential for building secure, multi-tenant applications and avoiding this insidious gotcha.