SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '54c4147c6ddad1ba9ef2614d395446da5befa6f76cc483989bf1c105264670b8' 
  AND token = 'Yzof0Kt9hSXzjKN2iaynrSok4YFcb102o2uWl99vPDM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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