SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'da82061efc920ada7e9e69434a4de11cb68a7ec9603798376f3accc30f6fc468' 
  AND token = 'Os+1DlsZalnFkt9hvUESnZvlNrDMPhSJ08jIvYKhxKo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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