Sandbox

SELECT 
  user_id, 
  helpdesk_user_id, 
  user_login, 
  company_id, 
  firstname, 
  lastname, 
  email, 
  user_type, 
  password_change_timestamp 
FROM 
  ushop_users 
WHERE 
  user_id = 0 
  AND status = 'A'

Query time 0.00084

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}