SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b8a5147a2510b1c4cf5904571e9725cba0ca1ff10f6df032e2b666147964d985' 
  AND token = 'mcmsx0npNG90RYfZB5/1sbyvlkriEJw690GCWbH8KQU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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