SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '66c8640fbe919810dc078216ef4b6e3868024fb9643505ccabf055bda7479924' 
  AND token = 'UVKqXVrOmeVqv4WnZB+zXku+J5+2BJxdn5m/jU4WETk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}