Supabase Rls

When to Use

Apply when implementing multi-tenant data isolation, user-specific data access, or any scenario requiring row-level authorization in Supabase.

Patterns

Pattern 1: User Owns Row

-- Source: https://supabase.com/docs/guides/auth/row-level-security
CREATE POLICY "Users can view own data"
ON todos FOR SELECT
USING (auth.uid() = user_id);

CREATE POLICY "Users can insert own data"
ON todos FOR INSERT
WITH CHECK (auth.uid() = user_id);

Pattern 2: Role-Based Access

-- Source: https://supabase.com/docs/guides/auth/row-level-security#policies-with-joins
CREATE POLICY "Admins full access"
ON todos FOR ALL
USING (
  EXISTS (
    SELECT 1 FROM profiles
    WHERE profiles.id = auth.uid()
    AND profiles.role = 'admin'
  )
);

Pattern 3: Organization/Tenant Isolation

-- Source: https://supabase.com/docs/guides/auth/row-level-security
CREATE POLICY "Org members access"
ON projects FOR SELECT
USING (
  org_id IN (
    SELECT org_id FROM org_members
    WHERE user_id = auth.uid()
  )
);

Pattern 4: Public Read, Auth Write

-- Source: https://supabase.com/docs/guides/auth/row-level-security
CREATE POLICY "Public read" ON posts
FOR SELECT USING (true);

CREATE POLICY "Auth users write" ON posts
FOR INSERT WITH CHECK (auth.uid() IS NOT NULL);

Anti-Patterns

• No RLS on sensitive tables - Always enable: ALTER TABLE x ENABLE ROW LEVEL SECURITY
• Using service_role in client - Bypasses RLS; use only server-side
• Complex JOINs in policies - Causes performance issues; denormalize if needed
• Forgetting FOR clause - Specify SELECT/INSERT/UPDATE/DELETE explicitly

Verification Checklist

• RLS enabled on table: ALTER TABLE x ENABLE ROW LEVEL SECURITY
• Policies exist for all needed operations (SELECT, INSERT, UPDATE, DELETE)
• Tested with auth.uid() returning expected user
• Service role operations stay server-side only
• No N+1 queries in policy JOINs