SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f0ff5ae71ea7063b48a6ce8352985555aa8f13dc5d372f3dc11a9286b5197466' 
  AND token = 'ycDDH68lqLQlWnhhZJYeHSXU5XGQm2ZFSpX6/MUa5FE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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