SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'eb6304d2946a6ac5d76e7a2e10576e5e6acda06eed945c44edec80a06ef668ea' 
  AND token = 'kmkeA2tZnHloV/bTjzSduyBeUwtHndy0O0ZoYe9Izdg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00055

JSON explain

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