SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '01ee40bbb4f068fd36256b8d13f99247c1f21f07844cf298bf3eea469d578802' 
  AND token = 'weXE5a4YSooTMYZRNtXCFyW4W8ITfecu/1tH2JWq5Ac=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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