برمجيات تداول تصمد عند ذروة الحجم.

-- Row-level tenant isolation.
-- One schema, many tenants, zero "where did this data leak from" tickets.

ALTER TABLE invoices ENABLE ROW LEVEL SECURITY;

CREATE POLICY tenant_isolation ON invoices
  USING (tenant_id = current_setting('app.tenant_id')::uuid);

-- Application sets the tenant for every connection.
-- If we forget, the query returns zero rows, not someone else's.
SET LOCAL app.tenant_id = '8f3a-...-c1';

SELECT id, amount_cents, status
  FROM invoices
 WHERE status = 'pending'
 ORDER BY created_at DESC
 LIMIT 25;