SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0affcc682d5efff21c393ce93490ca95ecdc7ea0ca90a950eee72869f1b1f50e' 
  AND token = 'OsTOvO09G6sFy7QgHFO3mJMOhtkxFHFNd4hWxpm5pIM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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