SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fc3f3572143717336faae37d898c3509343ece5485f40d1534c126e859e6fb43' 
  AND token = 'TPvuDk+po8LZTqqPg9ewbszVwH1H45JpUzON3PhASGg=' 
  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"
    }
  }
}